Electric power-assisted bicycle and speed control method thereof, and power-assisted sensor group

Abstract

The present disclosure provides an electric power-assisted bicycle and a speed control method thereof, and an assist sensor group. In the electric power-assisted bicycle, a first sensor has a first sensing mode, and the first sensing mode enables the first sensor to detect a first characteristic physical quantity. A second sensor has a second sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity. A controller is used to obtain a sensing signal of the assist sensor group. When the sensing signal corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on a first driving mode, so that a first motor control unit controls the torque of the motor according to the first motor control instruction and enters a first speed regulation mode accordingly. Alternatively, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on a second driving mode, so that a second motor control unit controls the torque of the motor according to the second motor control instruction and enters a second speed regulation mode accordingly.

Description

Technical Field

[0001] The present disclosure relates to the technical field of data processing, and in particular to an electric power-assisted bicycle and a speed control method thereof, and a power-assisted sensor group. Background Art

[0002] As people pay more and more attention to green travel and their requirements for travel convenience and comfort continue to increase, electric-assisted bicycles are becoming more and more popular in the market due to their advantages of combining human and electric power. Electric-assisted bicycles can provide timely assistance during the rider's pedaling process, effectively reducing the rider's physical exertion while retaining the fun of riding.

[0003] However, in the existing electric-assisted bicycle technology field, there are some technical problems that need to be solved urgently. Traditional electric-assisted bicycles often rely on only a single type of sensor to sense riding conditions, and then control the motor to provide assistance and speed regulation. For example, some electric-assisted bicycles only use sensors that detect a single physical quantity, the speed of the pedal, to achieve motor control. Although this single sensing mode can provide corresponding assistance based on the rider's pedaling action to a certain extent, it has obvious limitations.

[0004] On the one hand, it is difficult to fully and accurately match different riding scenarios and the actual needs of riders by controlling the motor based solely on a single physical quantity. For example, in a climbing scenario, riders may need greater torque to overcome the slope resistance. Relying solely on the pedal speed to control the motor output torque and speed regulation may not provide sufficient assistance, causing the rider to expend greater physical strength to climb the slope, seriously affecting the riding experience. On a flat road, if the motor is controlled according to the assistance strategy when climbing, the vehicle speed may be too fast, which poses certain safety risks and also causes unnecessary waste of electricity.

[0005] On the other hand, a single sensor has poor adaptability when facing complex and changing riding environments and the diverse riding habits of different riders. Different riders have different habits such as pedaling force and frequency. The detection of a single physical quantity cannot flexibly adjust the motor torque and speed mode according to these differences, making the motor power assistance effect unable to reach the optimal state and unable to meet the expectations of consumers for efficient, comfortable and personalized power assistance for electric power-assisted bicycles.

[0006] To sum up, existing electric-assisted bicycles have technical limitations in power-assist sensors and corresponding motor control modes, making it difficult to fully, accurately and adaptively control motor torque and speed according to different riding scenarios and rider habits, affecting the overall performance and user experience of electric-assisted bicycles. Summary of the invention

[0007] The present disclosure provides an electric power-assisted bicycle, a speed control method thereof, and a power-assisted sensor group.

[0008] According to a first aspect of the present disclosure, there is provided an electric power-assisted bicycle, which includes: a power-assisted sensor group, a controller, a motor control unit, and a motor;

[0009] The power assist sensor group includes at least one first sensor and at least one second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity;

[0010] The controller is used to obtain the sensor signal of the power-assisting sensor group, and when the sensor signal corresponds to the first characteristic physical quantity, generate a first motor control instruction based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensor signal corresponds to the second characteristic physical quantity, generate a second motor control instruction based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0011] According to a second aspect of the present disclosure, a speed control method for an electric-assisted bicycle is provided, characterized by comprising:

[0012] Acquire a sensing signal of a power-assist sensor group arranged on the electric power-assist bicycle, wherein the power-assist sensor group includes at least a first sensor and a second sensor, wherein the first sensor has a first sensing mode, wherein the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, wherein the second sensing mode is different from the first sensing mode, and wherein the second sensing mode enables the second sensor to detect a second characteristic physical quantity;

[0013] When the sensing signal corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0014] According to a third aspect of the present disclosure, there is provided a power assist sensor group, the power assist sensor group comprising at least one first sensor and at least one second sensor, the first sensor having a first sensing mode, the first sensing mode enabling the first sensor to detect a first characteristic physical quantity, the second sensor having a second sensing mode, the second sensing mode being different from the first sensing mode, the second sensing mode enabling the second sensor to detect a second characteristic physical quantity;

[0015] When the sensing signal of the power-assisting sensor group corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0016] In the disclosed solution, the electric power-assisted bicycle adopts a power-assisted sensor group, which includes a first sensor and a second sensor with different sensing modes, respectively detecting different characteristic physical quantities. For example, it is assumed that the first characteristic physical quantity detected by the first sensor is the pedaling force, and the second characteristic physical quantity detected by the second sensor is the running slope of the bicycle (the slope can be detected by an angle sensor or the like). When the rider is in a climbing scene, the second sensor detects the second characteristic physical quantity of a larger slope. At this time, after the controller receives the corresponding sensor signal, it generates a second motor control instruction based on the second driving mode, so that the motor control unit controls the motor to output a larger torque according to the instruction, so that the rider can climb the slope more easily, avoiding the situation where a single sensor only considers conventional physical quantities such as pedal speed and cannot provide sufficient power assistance. On the contrary, on a flat road, the first characteristic physical quantities such as the pedaling force detected by the first sensor are within the normal range. The controller generates a suitable first motor control instruction based on the corresponding first driving mode, controls the motor to enter the first speed regulation mode suitable for flat roads, and outputs appropriate torque to maintain a suitable vehicle speed. It will neither cause safety hazards due to excessive speed caused by excessive power assistance nor cause waste of electricity, and it is well adapted to the actual needs of different riding scenarios.

[0017] In addition, in this technical solution, due to the presence of the power-assisting sensor group, multiple sensors with different sensing modes work together. For example, for a rider who is used to pedaling vigorously, the first sensor detects the first characteristic physical quantity of the rider's greater pedaling force, and the controller can generate corresponding motor control instructions based on the signal and the corresponding first drive mode, so that the motor control unit controls the motor to output a torque that is suitable and matches the force, and enters the first speed regulation mode that conforms to the riding habit, making the riding process smoother and more comfortable. Similarly, for riders with a fast pedaling frequency but moderate force, the controller can accurately judge and generate appropriate motor control instructions based on the comprehensive characteristic physical quantities detected by different sensors, adjust the motor's torque and speed regulation mode, so that the power-assisting effect can be optimized according to the rider's personalized habits.

[0018] It should be understood that the contents described in the summary of the invention are not intended to limit the key or important features of the embodiments of the present disclosure, nor are they intended to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] The above and other features, advantages and aspects of the embodiments of the present disclosure will become more apparent with reference to the following detailed description in conjunction with the accompanying drawings. The accompanying drawings are used to better understand the present solution and do not constitute a limitation of the present disclosure. In the accompanying drawings, the same or similar reference numerals represent the same or similar elements, wherein:

[0020] Figure 1 This is a schematic structural diagram of an electric-assisted bicycle according to an embodiment of the present application.

[0021] Figure 2 This is a flow chart of a speed control method for an electric-assisted bicycle according to an embodiment of the present application.

[0022] Figure 3 This is a schematic diagram of the structure of a power assist sensor group according to an embodiment of the present application. DETAILED DESCRIPTION

[0023] In order to make the purpose, technical solution and advantages of the embodiments of the present disclosure clearer, the technical solution in the embodiments of the present disclosure will be clearly and completely described below in conjunction with the drawings in the embodiments of the present disclosure. Obviously, the described embodiments are part of the embodiments of the present disclosure, not all of the embodiments. Based on the embodiments in the present disclosure, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present disclosure.

[0024] In addition, the term "and / or" in this article is only a description of the association relationship between the associated objects, indicating that there can be three relationships. For example, A and / or B can represent: A exists alone, A and B exist at the same time, and B exists alone. In addition, the character " / " in this article generally indicates that the associated objects before and after are in an "or" relationship.

[0025] Figure 1 This is a schematic diagram of the structure of an electric-assisted bicycle according to an embodiment of the present application. Figure 1 As shown, it includes: a power assist sensor group, a controller, a motor control unit, and a motor;

[0026] The power assist sensor group includes at least one first sensor and at least one second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity;

[0027] The controller is used to obtain the sensor signal of the power-assisting sensor group, and when the sensor signal corresponds to the first characteristic physical quantity, generate a first motor control instruction based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensor signal corresponds to the second characteristic physical quantity, generate a second motor control instruction based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0028] In a specific application scenario, for the power assist sensor group:

[0029] (I) First sensor

[0030] The first sensor adopts a specific first sensing mode, which is based on a specific physical principle to detect the first characteristic physical quantity. For example, the first sensing mode can be based on the principle of strain gauges. The strain gauges are attached to the key stress-bearing parts of the bicycle pedals. When the rider steps on the pedals, the pedals are slightly deformed by force, and the resistance value of the strain gauges changes accordingly. The resistance change is converted into a measurable electrical signal through a matching measurement circuit (such as a Wheatstone bridge circuit), so as to detect the first characteristic physical quantity of the pedaling force. Of course, the first sensing mode can also be based on other principles, such as using the piezoelectric effect of piezoelectric ceramics to generate electric charges when subjected to pressure (pedaling force), and then obtaining the corresponding pedaling force-related electrical signals through a charge measurement circuit, as long as the set first characteristic physical quantity can be accurately detected.

[0031] From the perspective of sensor selection, if a strain gauge type first sensor is used, a high-precision, high-sensitivity metal foil strain gauge can be selected, which has good linearity and stability and can more accurately reflect the change in pedaling force. In terms of installation position, it is evenly distributed in key force areas such as the upper and lower surfaces of the connection between the pedal and the crank to ensure that the force conditions at different positions can be fully and accurately sensed, and the accurate pedaling force value can be comprehensively obtained.

[0032] (ii) Second sensor

[0033] The second sensing mode of the second sensor is different from the first sensing mode, and is intended to detect another second characteristic physical quantity that is of great reference value to motor control. For example, the second sensing mode can be based on the principle of an inclination angle sensor to detect the slope of the road on which the bicycle is located. A MEMS (micro-electromechanical system) inclination angle sensor can be used, which contains a micro-mechanical structure and a detection circuit. The inclination angle of the bicycle relative to the horizontal plane is determined by detecting the components of gravity in different directions, that is, the slope of the road, which is the second characteristic physical quantity. Alternatively, the second sensing mode can also be based on the principle of an acceleration sensor, by analyzing the acceleration change of the bicycle in the vertical direction, combined with a certain algorithm to infer whether it is currently in a climbing or descending state and the approximate situation of the slope, thereby realizing the detection of relevant characteristic physical quantities.

[0034] If a MEMS tilt angle sensor is used as the second sensor, a model with high precision, low power consumption and strong anti-interference ability should be selected to adapt to complex riding environments. The installation position can be selected in the center of the bicycle frame or near the handlebars, which is relatively stable and can accurately reflect the tilt of the entire vehicle, to ensure that the detected slope angle value is accurate and reliable, providing an accurate basis for subsequent motor control.

[0035] 3. Controller

[0036] The controller is equipped with a dedicated signal acquisition and processing module, which is connected to the power-assist sensor group through a suitable interface circuit (such as an analog signal input interface, a digital signal input interface, etc., depending on the type of sensor output signal) to obtain the sensor signals from the first sensor and the second sensor in real time. The acquired analog signals will be converted into digital signals through a built-in analog-to-digital converter (ADC), and then the built-in algorithm program of the microprocessor (which can be a common control chip such as a single-chip microcomputer) will be used to perform pre-processing operations such as filtering, amplification, and calibration on these digital signals, remove noise interference in the signals, and normalize the signals to ensure the accuracy of subsequent analysis and judgment.

[0037] 4. Drive mode judgment and instruction generation module

[0038] 1. Logic related to the first driving mode

[0039] After processing the sensor signal, when it is determined that the received sensor signal corresponds to the first characteristic physical quantity, the drive mode judgment and instruction generation module inside the controller will perform calculation processing according to the pre-set first drive mode algorithm logic. For example, taking the first characteristic physical quantity as the pedal stepping force as an example, if the pedaling force is detected to be in a lower range (such as 0-20 kgf), according to the rules set by the first drive mode, the corresponding motor control parameters are calculated through the built-in algorithm (which can be based on the proportional-integral-differential control algorithm, i.e., PID algorithm, and the control model is established according to the relationship between the pedaling force and the expected vehicle speed, motor torque and other parameters), and then the first motor control instruction is generated, which contains key control information such as the motor target torque value and the speed adjustment value, and is intended to allow the motor control unit to control the motor to output a suitable torque and enter the first speed control mode that matches it, such as when the pedaling force is small, the motor is controlled to output a small torque, so that the vehicle speed is steadily and slowly increased, to adapt to the rider's easy start or slow riding on a flat road.

[0040] 2. Second drive mode related logic

[0041] Similarly, when the sensing signal corresponds to the second characteristic physical quantity, for example, when the bicycle is detected to be on a road with a large slope (such as a slope greater than 5°), the second motor control instruction is generated based on the algorithm logic of the second driving mode (the PID algorithm or other suitable intelligent control algorithm can also be used, taking into account multiple factors such as the slope, the estimated weight of the rider, and the current vehicle speed), so that the motor control unit controls the motor to output a larger torque to help the rider climb the slope smoothly, and at the same time enters the second speed regulation mode that meets the requirements of the climbing scene, ensuring that the vehicle speed during the climbing process can meet the climbing requirements and ensure riding safety. In addition, the controller stores various parameter thresholds and control rule tables corresponding to different driving modes, which can be pre-determined and stored in the non-volatile memory (such as Flash memory) of the controller through experimental testing, simulation analysis, etc., so as to quickly and accurately perform judgment and instruction generation operations during actual riding.

[0042] 5. Motor Control Unit

[0043] The motor control unit is the key link connecting the controller and the motor. After receiving the motor control instructions from the controller (whether it is the first motor control instructions or the second motor control instructions), it has the functions of power amplification and signal conversion. It can convert the digital control signal from the controller into a high-power electrical signal suitable for motor drive (for example, for a brushless DC motor, the control instruction is converted into a corresponding PWM pulse width modulation signal to adjust the input voltage and current of the motor), so as to accurately control the torque and speed of the motor, and operate the motor according to the predetermined first speed regulation mode or the second speed regulation mode to meet the power assistance requirements under different riding scenarios and rider operations.

[0044] 6. Motor

[0045] The motor can be a common DC brushless motor or hub motor suitable for electric-assisted bicycles. Taking the DC brushless motor as an example, it has the advantages of high efficiency, low noise, and long life. It is composed of a stator, a rotor, and the corresponding electronic commutation circuit. After receiving the appropriate control signal from the motor control unit, the rotor rotates and the torque and speed are precisely adjusted by changing the power-on sequence and current of the stator winding, thereby driving the bicycle wheel to rotate and provide corresponding assistance to the rider. The motor can operate stably and reliably in different speed regulation modes to meet the power requirements of electric-assisted bicycles under various working conditions.

[0046] Optionally, the first speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a first user state, and the second speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a second user state, and the first user state is different from the second user state.

[0047] To this end, in the specific implementation:

[0048] 1. About the First User State and the First Speed ​​Adjustment Mode

[0049] (I) Definition of the first user state and related parameters

[0050] 1. Description of state characteristics The first user state can be defined based on a variety of factors. For example, it can be set to a state where the rider rides at a relatively low intensity. Specifically, the rider's pedaling frequency is in a relatively low range (such as 30-50 pedaling times per minute), and the pedaling force is relatively small (such as the average pedaling force is between 0-20 kgf), and the bicycle may be traveling on a relatively flat road with a road slope close to 0°, and the external environment has little resistance to riding. These parameters can be acquired in real time through corresponding sensors (such as a first sensor to detect pedaling force, a speed sensor installed on the frame to calculate the pedaling frequency in combination with time, and a second sensor to detect the road slope, etc.) and fed back to the controller for comprehensive judgment.

[0051] 2. Examples of applicable scenarios Common applicable scenarios include leisurely riding in the park or short-distance slow riding in the community. At this time, riders pay more attention to the comfort and leisurely experience of riding, and do not need too high a speed or too much motor assistance.

[0052] (II) Specific configuration of the first speed regulation mode

[0053] 1. Motor torque setting

[0054] In the first speed control mode, based on the characteristics of the first user state, the controller generates the first motor control instruction through the first driving mode to configure the motor control unit to control the motor to output a relatively small torque. For example, according to a pre-set algorithm (the appropriate motor torque relationship under different pedaling frequencies, forces and road conditions can be determined based on experimental tests and theoretical modeling), the torque range of the motor output in this state can be set to between 0-10 Nm, which is sufficient to assist the rider to maintain a relatively stable and slow speed, meeting the needs of easy riding.

[0055] 2. Vehicle speed adjustment strategy

[0056] For vehicle speed regulation, the first speed regulation mode follows the principle of steady speed increase and maximum speed limit. For example, after the initial speed is set to start from 0, as the rider pedals, the vehicle speed increases at a relatively slow rate, and the speed increase is controlled at about 5-10 kilometers per hour per minute, and the maximum speed is limited to 15 kilometers per hour to avoid excessive speed affecting riding comfort and safety. This speed regulation process is achieved through the precise control of the motor speed by the motor control unit. The motor control unit adjusts the input voltage and current of the motor (such as using PWM pulse width modulation technology to change the duty cycle to control the speed of the DC brushless motor) according to the first motor control instruction containing the speed adjustment value transmitted by the controller to achieve the predetermined speed regulation effect.

[0057] 3. Power output response characteristics

[0058] In the first speed regulation mode, the power output response of the motor has a relatively gentle characteristic. That is, when the rider's pedaling force or frequency changes slightly, the adjustment of the motor torque and vehicle speed is also gradual, and there will be no sudden and large changes. For example, if the rider slightly increases the pedaling force, the increase in motor torque will increase slowly according to a certain proportional coefficient (this coefficient can be determined through multiple experimental adjustments, such as setting the motor torque to increase by 2 Nm for every 5 kg increase in pedaling force), and the vehicle speed will also increase steadily, giving the rider a natural and comfortable power-assisting feeling, which meets the requirements of easy riding in the first user state.

[0059] 2. About the Second User State and the Second Speed ​​Adjustment Mode

[0060] (I) Second User Status Definition and Related Parameters

[0061] 1. Status feature description

[0062] The second user state can be defined as a state where the rider rides at a higher intensity, which is significantly different from the first user state. Its characteristics may be reflected in the rider's pedaling frequency being in a higher range (such as 60-100 pedalings per minute), the pedaling force being larger (the average pedaling force is between 20-50 kgf), and the bicycle may be climbing a slope or need to pass a certain section of road quickly, the road slope has a certain value (such as a slope greater than 5°), and the external resistance faced is large (such as environmental factors that increase resistance such as driving against the wind). Similarly, the parameters related to these states also rely on the power-assisting sensor group (pedaling force sensor, slope sensor, and possibly wind direction and speed sensor to judge the external resistance situation) to collect information in real time and pass it to the controller for judgment and identification.

[0063] 2. Examples of applicable scenarios

[0064] Typical application scenarios include riding uphill in mountainous areas or accelerating on suburban roads to reach the destination as quickly as possible. At this time, the rider needs more powerful motor assistance to overcome greater resistance, achieve smooth riding and maintain a certain speed.

[0065] (II) Specific configuration of the second speed regulation mode

[0066] 1. Motor torque setting

[0067] In view of the greater resistance faced by riders in the second user state, in the second speed control mode, the controller will configure the motor control unit to control the motor to output a greater torque based on the second motor control command generated by the second drive mode. According to the actual situation and the pre-set algorithm (comprehensively considering the relationship between multiple factors such as slope, pedaling force, external resistance and motor torque, and determining the appropriate torque output value through a large number of experiments and simulation analysis), the torque range of the motor output can be set between 15-30 Nm. Such a large torque can help riders effectively overcome resistance such as slope and headwind, ensuring that riding can continue.

[0068] 2. Vehicle speed adjustment strategy

[0069] In terms of speed regulation, the second speed regulation mode will pay more attention to maintaining a stable speed according to the actual resistance and the needs of the rider, ensuring that there will be no sudden drop in speed under greater resistance. For example, during the climbing process, even if the rider's pedaling force fluctuates to a certain extent, the motor control unit can accurately control the motor to keep the speed as stable as possible in a relatively reasonable range (such as 8-12 kilometers per hour) to ensure the continuity and safety of riding. This is achieved by dynamically adjusting the input parameters of the motor through the motor control unit (such as changing the motor's power supply voltage, current, and PWM signal duty cycle in real time according to real-time monitoring of slope changes and pedaling force changes) to achieve stable control of the vehicle speed and adapt the vehicle speed to complex riding conditions.

[0070] 3. Power output response characteristics

[0071] In the second speed control mode, the power output response of the motor is relatively sensitive and powerful. When the rider's pedaling force or frequency changes, the motor can quickly make corresponding torque and speed adjustments to better match the rider's needs to overcome resistance and maintain speed. For example, when the rider increases the pedaling force to try to speed up the climbing speed, the motor torque will quickly increase according to the set proportional relationship (such as for every increase of 10 kg of pedaling force, the motor torque will increase by 5 Nm), and the speed will also increase to the appropriate range as soon as possible, allowing the rider to feel that the motor power assist is timely and effectively assisting him to cope with high-intensity riding conditions.

[0072] Optionally, the electric assisted bicycle further includes: a speed mode switching component, used to capture the user's speed mode switching action to generate a speed mode switching instruction, and the controller is used to execute sensor switching according to the speed mode switching instruction, and the sensor switching includes: switching from the first sensor to the second sensor to switch from the first speed mode to the second speed mode, or, switching from the second sensor to the first sensor to switch from the second speed mode to the first speed mode.

[0073] To this end, in the specific implementation:

[0074] 1. Speed ​​regulation mode switching component

[0075] (I) Component composition and principle

[0076] 1. Physical structure

[0077] The speed mode switching component can be implemented in many forms. A common one is a manually operated button structure set on the handlebar of the bicycle, which is convenient for the rider to operate during riding. For example, it can be composed of two buttons, one button is marked as "boost" (for switching from the first speed mode to the second speed mode), and the other button is marked as "boost" (for switching from the second speed mode to the first speed mode). The two buttons can be made of waterproof and wear-resistant plastic material, and the internal micro switch and other mechanical structures are connected to the circuit to ensure reliable triggering operation.

[0078] In addition, a touch-sensitive switching component can also be used, and the touch-sensitive area can be integrated in a suitable position of the handlebar (such as the side or top of the handlebar). The rider's touch action can be detected through the capacitive touch sensing principle. Different touch areas or touch methods (such as long press, short press, sliding, etc.) can also be distinguished to correspond to different speed control mode switching functions. This method has a simpler and more beautiful appearance, and the operation has a certain sense of technology.

[0079] 2. Signal generation mechanism

[0080] Take the button-type speed mode switching component as an example. When the rider presses the "boost boost" button, the internal micro switch is closed, the circuit is turned on, and a low-level (or high-level, depending on the logic convention of the circuit design) trigger pulse signal is generated. This signal serves as the speed mode switching instruction from the first speed mode to the second speed mode. Similarly, when the "boost reduction" button is pressed, a corresponding trigger pulse signal is also generated as the switching instruction from the second speed mode to the first speed mode.

[0081] For the touch-sensing switching component, when the rider operates in the corresponding touch-sensing area, the touch-sensing chip detects the change in capacitance, and after the built-in signal processing circuit (such as amplification, filtering, analog-to-digital conversion, etc.), converts the touch action into a speed mode switching instruction in the corresponding digital signal format, which is sent to the controller to indicate the speed mode switching operation that needs to be performed.

[0082] (II) Installation location and wiring considerations

[0083] 1. Reasonable installation location

[0084] Regardless of the form of speed mode switching components, the installation location must fully consider the convenience and safety of the rider's operation. Installing it on the handlebar is an ideal choice. For example, the button-type components are installed near the gripping position on both sides of the handlebar, which is convenient for the rider to press the operation with their fingers, and will not affect the normal grip and steering of the handlebar. The touch-sensitive type can be reasonably arranged in the area of ​​the handlebar that is easy for the fingers to reach, ensuring that the rider can complete the touch operation without diverting too much attention during riding.

[0085] 2. Wiring design

[0086] The signal line from the speed mode switching component needs to be properly routed to avoid interference with other bicycle parts (such as brake cables, gear cables, etc.), and the line must be protected to prevent damage from external forces, moisture, etc. The signal line is generally made of flexible and insulated wires, laid along the wire trough inside the bicycle frame or using wire pipes, and finally connected to the corresponding input interface of the controller to ensure that the signal can be accurately transmitted to the controller.

[0087] 2. Controller processing of switching instructions and sensor switching implementation

[0088] (I) Interface and signal reception

[0089] The controller has a dedicated external signal input interface for receiving the speed mode switching instruction from the speed mode switching component. The interface can be a digital input interface (such as a GPIO interface for switching instructions in the form of digital signals), and is configured with corresponding level detection circuits and anti-shake circuits to prevent false trigger signals due to external interference or button jitter. For switching instructions in the form of analog signals (such as the continuously changing analog quantity output by some special touch-sensitive components to indicate different operation intentions), they will be converted into digital signals through an analog-to-digital conversion circuit for subsequent processing.

[0090] (II) Instruction analysis and logical judgment

[0091] 1. Instruction recognition logic

[0092] When the controller receives the speed control mode switching instruction, it will first identify the instruction through the built-in program code. For example, if it receives a digital signal of a specific level sequence generated by pressing the "boost increase" button (such as two consecutive low-level pulses, which is only an example and can be determined according to the specific design), it is judged as an instruction to switch from the first speed control mode to the second speed control mode; if it receives a corresponding level sequence signal corresponding to the "boost reduction" button, it is judged as an instruction to switch from the second speed control mode to the first speed control mode.

[0093] 2. Sensor switching control logic

[0094] Once the direction of the speed control mode switching is determined, the controller performs the corresponding sensor switching operation. When switching from the first speed control mode to the second speed control mode, the controller cuts off the signal connection path with the first sensor by controlling the corresponding multiplexer (MUX) circuit or the logic switch configured by software, and establishes the signal connection path with the second sensor at the same time, so that the sensor signal obtained subsequently comes from the second sensor, thereby generating the corresponding motor control instruction according to the second driving mode based on the second characteristic physical quantity detected by the second sensor, and entering the second speed control mode.

[0095] On the contrary, when switching from the second speed regulation mode to the first speed regulation mode, the controller uses the same circuit or logic control means to disconnect the second sensor, reconnect the first sensor, and generate a motor control instruction according to the first driving mode based on the first characteristic physical quantity of the first sensor, so that the system returns to the first speed regulation mode. In addition, during the sensor switching process, the controller will synchronously adjust the relevant signal processing parameters (such as signal amplification factors and filter coefficients for different sensors, because the output signal characteristics of different sensors may be different) to ensure that the sensor signals received subsequently can be accurately processed, and ensure that the entire speed regulation mode switching process is carried out smoothly and reliably.

[0096] Optionally, the first sensor is installed on the pedal force transmission center shaft, or at the connection between the pedal force arm and the power output sprocket; and / or, the second sensor is installed on the pedal force arm, or on the wheel axle power adapter.

[0097] To this end, in the specific implementation:

[0098] 1. Installation location of the first sensor and related considerations

[0099] (I) Installed on the pedal force transmission shaft

[0100] 1. Installation method and principle

[0101] The pedal force transmission shaft is one of the key components that transmits and converts the rider's pedaling force into the driving force of the bicycle. When the first sensor is installed here, an embedded installation method can usually be adopted. For example, for the first sensor based on the principle of strain gauges to detect the pedaling force, a flat installation surface or groove can be processed at a suitable position of the shaft (generally a position where the force is more concentrated and can accurately reflect the overall pedaling force, such as near the connection between the side of the shaft and the crank), and then the strain gauge is pasted on the plane and connected to the corresponding signal processing circuit (such as the Wheatstone bridge circuit mentioned above) through a wire.

[0102] When the rider pedals, the pedaling force is transmitted to the middle shaft through the crank, and the middle shaft will produce corresponding axial or radial deformation. The strain gauge attached to its surface will change its own resistance value as the middle shaft deforms, and then convert the change in the magnitude of the pedaling force into a measurable electrical signal change, thereby achieving accurate detection of the pedaling force (i.e. the first characteristic physical quantity).

[0103] 2. Advantages and precautions

[0104] The advantage of installing the first sensor on the pedal force transmission shaft is that the transmission of the original force generated by the rider's pedaling can be directly obtained here, and the detected pedaling force data is relatively more accurate and comprehensive, which can reflect the actual size and change trend of the force during the entire pedaling process. At the same time, since the structure of the shaft itself is relatively stable, the sensor is less affected by external interference (such as vibration, bumps and other external factors during riding) after installation, which is conducive to improving the stability and reliability of the sensor signal.

[0105] However, during the installation process, it is important to ensure that the installation operation does not damage the original structural strength and normal transmission function of the middle axis. For example, when processing the installation plane or groove, the dimensional accuracy and depth must be controlled to avoid weakening the bearing capacity of the middle axis, and the sealing and protection of the sensor and wires must be done well to prevent damage to the sensor or abnormal signal due to water or dust ingress during riding.

[0106] (ii) Installed at the connection between the pedal arm and the power output sprocket

[0107] 1. Installation method and principle

[0108] The first sensor is installed at the connection between the pedal lever and the power output sprocket, which can also be realized based on the force measurement principle such as strain gauges. The installation here can adopt a set-type or clamp-type auxiliary structure, first fix the strain gauge and other sensor elements inside these auxiliary structures, and then install the auxiliary structure at a suitable position at the connection so that it can fit the force-bearing surface closely and accurately sense the force transmission.

[0109] When the rider steps on the pedal to drive the pedaling lever arm to move, there will be force transmission and interaction between the lever arm and the power output sprocket. The force generated in this process will cause slight deformation of the connection. The sensor can capture these deformations and convert them into corresponding electrical signals, thereby measuring the first characteristic physical quantity, the pedaling force.

[0110] 2. Advantages and precautions

[0111] The advantage of this installation position is that it focuses more on detecting the actual situation when the pedaling force is about to be converted into the sprocket rotation power, which is of great significance for analyzing the impact of the pedaling force on the sprocket drive effect and the subsequent transmission chain. Moreover, compared with directly installing it on the middle axis, the installation and maintenance here may be relatively easier, and it is easier to remove and replace the sensor when a sensor failure occurs.

[0112] However, it should be noted that since this is a key link in power transmission, the force conditions are relatively complex, and the sensor has to withstand forces from different directions as well as certain vibrations and impacts, so the sensor's impact resistance and stability are required to be higher. When selecting the sensor model and designing the installation structure, these factors should be fully considered to ensure that the sensor can work stably for a long time under a complex force environment, and that the installation structure cannot affect the normal connection and transmission efficiency between the arm and the sprocket.

[0113] 2. Second sensor installation location and related considerations

[0114] (I) Installed on the pedal arm

[0115] 1. Installation method and principle

[0116] If the second sensor is installed on the pedaling lever, for example, to detect the second characteristic physical quantity of pedaling frequency, a photoelectric sensor can be used. A light-emitting element (such as an infrared light-emitting diode) is installed on one side of the lever, and a corresponding light-receiving element (such as a phototransistor) is installed on the other side. When the lever swings up and down as the rider pedals, it will periodically block the light, and the light signal received by the light-receiving element will show periodic changes. By detecting and analyzing the frequency of the light signal change, the physical quantity of pedaling frequency can be obtained.

[0117] Alternatively, if you want to detect relevant physical quantities such as the swing angle of the lever arm to indirectly reflect other situations that are valuable to motor control (such as inferring the rider's force method through angle changes, etc.), you can use an angle sensor. Install the angle sensor near the rotation joint of the lever arm through a suitable mechanical fixing device, so that it can accurately measure the angle changes as the lever arm swings, thereby providing a basis for subsequent motor control.

[0118] 2. Advantages and precautions

[0119] The advantage of installing it on the pedal lever is that it can directly obtain dynamic information closely related to the rider's pedaling action, which is very useful for real-time understanding of the rider's operating habits and immediate status. Moreover, the close combination of the sensor and the pedal lever makes the acquired data more closely related to the rider's actual pedaling behavior, and can more accurately assist in adjusting the motor control strategy.

[0120] However, when installing the sensor here, it is important to ensure that the size and installation method of the sensor do not hinder the rider's normal pedaling action, add additional resistance, or change the original swing characteristics of the lever. At the same time, the sensor line should be arranged properly to prevent the line from being pulled, entangled or damaged during the swing of the lever, so as to ensure the stability of signal transmission.

[0121] (ii) Installed on the axle power adapter

[0122] 1. Installation method and principle

[0123] The wheel-axle power adapter plays a key role in connecting the wheel and sprocket transmission components in the power transmission system of the bicycle. Installing the second sensor here has a unique detection purpose. For example, if you want to detect the actual speed of the bicycle, which is the second characteristic physical quantity, you can install a magnetic sensor in combination with the magnetic mark on the wheel axle to achieve this. Install a magnetic sensor (such as a Hall sensor) at a suitable position on the wheel-axle power adapter, and evenly arrange several magnetic marks (such as small magnets) on the wheel axle. As the wheel rotates, the magnetic marks pass through the magnetic sensor in turn, which will cause periodic changes in the magnetic field around the sensor. By detecting the frequency of this magnetic field change and combining it with parameters such as the circumference of the wheel, the speed of the bicycle can be accurately calculated.

[0124] In addition, if you want to detect the resistance conditions of the bicycle (for example, to determine whether it is on a flat road or climbing a slope, facing headwind, and other different resistance scenarios), you can install a pressure sensor or a strain force sensor. By detecting the changes in pressure from the wheel and the direction of force applied to the axle power adapter under different road conditions, and through certain algorithm analysis, you can infer the current driving resistance conditions, thereby providing a reference for motor control.

[0125] 2. Advantages and precautions

[0126] The advantage of installing the second sensor on the wheel axle power adapter is that it can directly reflect the overall power transmission and driving status of the bicycle, which plays an important role in comprehensively judging the riding environment, the actual operating conditions of the vehicle, and accurately formulating the motor control strategy. Moreover, the sensor is installed in a relatively fixed position close to the core part of the power transmission, which is relatively less affected by the external environment and has better signal stability.

[0127] However, the spatial layout and structural characteristics of the wheel axle power adapter must be fully considered during installation to ensure that the sensor installation will not affect its normal power transfer function and will not interfere with other components (such as brake components, chains, etc.). At the same time, the sensor must be properly protected to prevent damage in complex road environments (such as water, mud, sand, etc.) to ensure long-term reliable operation.

[0128] Optionally, the first sensor is at least one of a torque sensor, a pressure sensor, or a stress sensor; or the second sensor is at least one of a velocity sensor, an angular velocity sensor, and a displacement sensor.

[0129] Optionally, the first sensor generates a first characteristic physical quantity by detecting the pressure exerted on the pedal, and the second sensor generates a second characteristic physical quantity by detecting the rotation frequency of the pedaling lever arm.

[0130] Optionally, in the first speed regulation mode, the speed of the electric assisted bicycle is proportional to the pedaling force borne by the pedal and has nothing to do with the rotation frequency of the pedaling force arm rod; in the second speed regulation mode, the speed of the electric assisted bicycle is proportional to the rotation frequency of the pedaling force arm rod and has nothing to do with the pedaling force.

[0131] To this end, in the specific implementation:

[0132] 1. Refinement of the First Characteristic Physical Quantity Detected by the First Sensor

[0133] (I) Sensor selection and principle

[0134] The first sensor may be a pressure sensor to detect the pressure on the pedal to generate a first characteristic physical quantity. Specifically, a thin film pressure sensor may be used, which contains an elastic sensitive element (such as an elastic film) and a strain gauge or a piezoelectric element. When the pedal is stepped on by the rider and is subjected to pressure, the pressure will be transmitted to the thin film pressure sensor, causing the elastic film to deform.

[0135] If it is a pressure sensor based on the strain gauge principle, the deformation of the elastic film will cause the resistance value of the strain gauge pasted on its surface to change. The resistance change is converted into an electrical signal through the matching Wheatstone bridge circuit. The size of the electrical signal corresponds to the pressure exerted on the pedal. After subsequent signal processing and calibration, the first characteristic physical quantity that accurately characterizes the size of the pedal pressure can be obtained.

[0136] If a piezoelectric pressure sensor is used, the pressure generated by the deformation of the elastic film acts on the piezoelectric element, causing it to generate electric charge due to the piezoelectric effect. The amount of charge is proportional to the pressure. The electrical signal related to the pedal pressure can be obtained through the charge amplification and detection circuit to determine the first characteristic physical quantity.

[0137] (II) Installation location and method

[0138] In terms of installation, it is a more appropriate choice to install the pressure sensor below the connection between the pedal and the crank. The pressure sensor can be tightly fitted on the force-bearing surface at the bottom of the pedal through a special card slot or embedded installation structure to ensure that the pressure on the pedal can be directly and accurately sensed. At the same time, the sensor and the surrounding structure must be sealed to prevent dust, water vapor and other impurities from entering and affecting the sensor performance, and to ensure that the installation of the sensor will not change the original pedaling comfort and mechanical properties of the pedal, ensuring the normal pedaling experience of the rider.

[0139] 2. Refinement of the Second Characteristic Physical Quantity Detected by the Second Sensor

[0140] (I) Sensor selection and principle

[0141] In order to detect the rotation frequency of the pedal lever to generate the second characteristic physical quantity, a photoelectric encoder can be used as the second sensor. The photoelectric encoder is mainly composed of a light source (such as a light emitting diode), a code disk and a photodetector (such as a phototransistor). The code disk is installed on the rotating shaft of the pedal lever and rotates synchronously with the lever. The code disk is engraved with evenly distributed light-transmitting and opaque stripes or holes.

[0142] When the pedal lever rotates, the code disk rotates accordingly, and the light emitted by the light source is received by the photodetector through the light-transmitting part of the code disk, while the opaque part blocks the light. The light signal received by the photodetector will show periodic changes. By detecting and counting the frequency of the light signal changes, the rotation frequency of the pedal lever can be obtained, which is the second characteristic physical quantity. The photoelectric encoder has the characteristics of high precision and high resolution, and can accurately measure the rotation frequency to meet the needs of practical applications.

[0143] (II) Installation location and method

[0144] It is ideal to install the photoelectric encoder at the end of the rotating shaft of the pedal lever. A special coupling or a clamping installation fixture can be used to ensure that the code disc and the rotating shaft of the lever are tightly connected to ensure the synchronization of the two rotations. At the same time, the positions of the light source and the photoelectric detector should be arranged reasonably so that they are at a suitable distance and angle relative to the code disc to ensure the accuracy of light transmission and reception. In addition, the entire photoelectric encoder should be effectively protected to avoid being affected by external collisions, dust, water vapor and other factors to ensure its stable and reliable operation.

[0145] 3. Refinement of speed control in the first speed regulation mode

[0146] (I) Control principle and algorithm

[0147] In the first speed regulation mode, the speed of the electric bicycle is set to be proportional to the pedal force borne by the pedal, and has nothing to do with the rotation frequency of the pedal force arm. A specific control algorithm is run inside the controller to achieve this function, such as an algorithm based on proportional control (P control).

[0148] First, the electrical signal corresponding to the pedal force borne by the pedal is obtained through the first sensor, and after analog-to-digital conversion and signal processing, a value representing the magnitude of the pedal force is obtained. Then, according to a pre-set proportionality coefficient (the coefficient can be obtained through multiple experimental tests, measuring the vehicle speed under different pedal forces and performing data analysis, for example, setting that for every increase of 10 kg of pedal force, the vehicle speed increases by 5 km / h), the controller uses the proportionality coefficient to calculate the corresponding target vehicle speed value.

[0149] After the motor control unit receives the motor control command generated by the controller based on the pedaling force, it controls the motor to output the corresponding torque by adjusting the motor's input voltage, current and other parameters (for example, using PWM pulse width modulation technology to adjust the duty cycle of the PWM signal according to the motor torque and speed requirements corresponding to the target vehicle speed), thereby driving the bicycle to travel at the target speed. During the entire process, the rotation frequency of the pedaling force arm is not considered, and the vehicle speed is adjusted only according to the pedaling force.

[0150] (II) Parameter setting and adjustment

[0151] In practical applications, it is necessary to reasonably set and adjust control parameters such as the proportional coefficient according to the specific specifications of the electric-assisted bicycle (such as wheel size, motor power, etc.) and the riding habits of the target user group. For example, for electric-assisted bicycles suitable for leisure riding, the proportional coefficient can be set relatively small, so that the speed changes more slowly with the pedaling force, providing a more comfortable and relaxed riding experience; and for models that tend to be sports-oriented, the proportional coefficient can be appropriately increased so that the speed can respond more quickly to the change in pedaling force and meet the rider's pursuit of speed. In addition, during the use of the bicycle, these control parameters can also be remotely adjusted through wireless communication interfaces (such as Bluetooth modules, which are convenient for connecting to external devices such as mobile phone apps) to adapt to different riding scenarios and changes in personal preferences.

[0152] 4. Refinement of speed control in the second speed regulation mode

[0153] (I) Control principle and algorithm

[0154] In the second speed regulation mode, the speed of the electric bicycle is proportional to the rotation frequency of the pedaling force arm and has nothing to do with the pedaling force. Similarly, the controller relies on a specific control algorithm to achieve this control logic, and a PID (proportional-integral-differential) control algorithm based on frequency feedback can be used here.

[0155] The photoelectric encoder is used as the second sensor to obtain the rotation frequency information of the pedal lever in real time and transmit the corresponding electrical signal to the controller. After processing the signal, the controller inputs the current rotation frequency value into the PID control algorithm module. The PID algorithm calculates the corresponding motor control instructions based on the pre-set parameters (proportional gain, integral time constant, differential time constant, etc., which are determined by system modeling, experimental debugging, etc. to ensure that the vehicle speed can be accurately controlled according to the rotation frequency) and the relationship between the desired vehicle speed and the rotation frequency.

[0156] The motor control unit adjusts the operating state of the motor according to the received instructions (such as changing the motor's power supply voltage, current and commutation frequency. For a brushless DC motor, precise control of these parameters can achieve different speeds and torque outputs), so that the bicycle speed and the rotation frequency of the pedaling force arm maintain a predetermined proportional relationship, achieving a stable and compliant speed regulation function without considering the influence of pedal force on the vehicle speed in the process.

[0157] (II) Parameter optimization and adaptability

[0158] In order to make the vehicle speed control in the second speed regulation mode more accurate and stable, it is necessary to continuously optimize the parameters of the PID control algorithm. For example, in different riding environments (such as flat roads, gentle slopes, steep slopes, etc.), a large amount of rotation frequency and vehicle speed data is collected through actual tests, and the proportional gain, integral time constant and differential time constant are fine-tuned to improve the algorithm's adaptability to different road conditions and riding states.

[0159] At the same time, taking into account the differences in pedaling habits of different riders (for example, some riders' pedaling frequency changes quickly, while others are relatively stable), an adaptive adjustment function can be set in the controller to automatically adjust the PID algorithm parameters according to the changing trend and characteristics of the rotation frequency during riding, to ensure that the vehicle speed can accurately follow the changes in the rotation frequency of the pedaling lever, thereby providing a good riding experience for different riders.

[0160] The above is an explanation of the present application scheme using the application scenarios of uphill and downhill as examples. In fact, the scheme of the embodiment of the present application can also be used in the following scenarios:

[0161] The torque sensor (TorqueSensor) (as the first sensor) detects the pedaling force signal of the vehicle and generates a motor torque proportional to the pedaling force through an algorithm to drive the vehicle. Therefore, the vehicle power increases with the increase of the pedaling force. The cadence sensor (CadenceSensor) (as the second sensor), also known as the speed sensor in the industry, calculates the motor torque to drive the vehicle by detecting the operation signal (pedaling frequency) of the vehicle crank. The characteristics of the two sensors determine the power assistance of the corresponding vehicle. The power control of the TorqueSensor is more natural. The power will change with the pedaling force of the rider to achieve a natural riding effect, which is suitable for people who have requirements for riding or are relatively professional in bicycle riding. Under the power assistance mode of the CadenceSensor, the vehicle power has nothing to do with the pedaling force, but only with the rotation frequency of the crank. This type of vehicle is suitable for people with poor physical condition or bad knee joints.

[0162] To this end, when implementing this application scenario:

[0163] For the power assist sensor group:

[0164] (1) First sensor (torque sensor-TorqueSensor)

[0165] The torque sensor (TorqueSensor) uses a specific first sensing mode to detect the first characteristic physical quantity, that is, the pedaling force signal of the vehicle. Its working principle is based on the strain effect of the strain gauge. High-precision strain gauges are installed in key force-bearing parts of the electric-assisted bicycle, such as the middle axis or the connection between the crank and the sprocket. When the rider applies force to the pedal, these parts will produce corresponding deformation, and the strain gauge attached to it will also deform accordingly, which will cause the resistance value of the strain gauge itself to change.

[0166] By constructing a Wheatstone bridge circuit, connecting strain gauges to each arm of the bridge, and using the correspondence between the unbalanced output of the bridge and the change in resistance of the strain gauge, the mechanical deformation is converted into a change in the electrical signal, thereby accurately measuring the pedaling force. In addition, in order to improve the measurement accuracy and stability, multiple strain gauges are usually used to form a full-bridge or half-bridge circuit, and in conjunction with the corresponding signal conditioning circuit, the collected weak electrical signals are amplified, filtered, and other pre-processing operations are performed to remove noise interference, and obtain a clear and accurate electrical signal reflecting the pedaling force, that is, the sensing signal corresponding to the first characteristic physical quantity.

[0167] In terms of sensor selection, it is more appropriate to use a torque sensor made of metal foil strain gauges with high sensitivity, good linearity and low hysteresis. For example, some well-known brands have launched torque sensor products designed for bicycle applications, which can provide accurate measurement results within a wide pedal force range (such as 0-1000N).

[0168] In terms of installation position, if you choose to install it at the middle axis, you can process several flat installation surfaces along the axial direction on the side of the middle axis, accurately paste the strain gauges on these surfaces, and do a good job of sealing protection to prevent water and dust from entering and affecting the performance of the sensor. At the same time, the strain gauge is connected to the signal processing circuit board located inside the frame through a wire to ensure stable signal transmission. If installed at the connection between the crank and the sprocket, a special clamp or slot structure can be used to firmly install the sensor at the key force-bearing position, so that it can accurately sense the deformation during the pedaling force transmission process, and also lead the signal to the subsequent processing circuit through reasonable wiring.

[0169] (2) Second sensor (cadence sensor-CadenceSensor)

[0170] The cadence sensor uses the second sensing mode to detect the second characteristic physical quantity, that is, the operation signal of the vehicle crank (pedaling frequency). Common implementation methods are magnetic sensors or photoelectric sensors based on the Hall effect principle.

[0171] Taking the Hall effect sensor as an example, a small magnet is installed on one side of the crank, and a Hall sensor is installed at the corresponding fixed position of the frame. When the crank rotates as the rider pedals, the magnet also rotates synchronously. Every time it passes the position of the Hall sensor, the Hall sensor will generate a pulse signal due to the change in the magnetic field. By counting the number of pulse signals per unit time, the crank rotation frequency can be accurately obtained, that is, the sensor signal corresponding to the second characteristic physical quantity of pedaling frequency.

[0172] If a photoelectric sensor is used, a code disc with light-transmitting and opaque stripes is installed on the rotating shaft of the crank, a light-emitting diode is fixed on one side of the code disc as a light source, and a phototransistor is installed at the corresponding position on the other side as a light receiving element. When the crank rotates, the code disc rotates with it, and the light signal received by the phototransistor will show periodic changes. Similarly, the pedaling frequency is calculated by detecting the frequency of the light signal change.

[0173] For the Hall Effect pedaling sensor, select a Hall sensor element with high sensitivity, fast response characteristics and good anti-interference ability to ensure that the magnetic field change signal generated by the crank rotation can be accurately captured. During installation, the distance and relative position between the magnet and the Hall sensor must be accurately adjusted to ensure that the magnetic field change can effectively trigger the sensor to generate a pulse signal. Generally, the distance between the two is kept at about a few millimeters, and the sensor must be firmly installed on the frame to prevent position deviation caused by vibration and other factors from affecting signal acquisition.

[0174] If it is a photoelectric cadence sensor, choose a photoelectric sensor assembly with high resolution and good stability. The stripe accuracy of the code disk should be able to meet the requirements of accurate measurement of rotation frequency. For example, the number of stripes can be designed to be 60 or more per revolution according to the required measurement accuracy. During installation, ensure that the code disk is closely connected to the crankshaft to ensure synchronous rotation. At the same time, the light source and the light receiving element should be installed at a suitable angle and distance to avoid external light interference and ensure the accuracy of light signal transmission and reception. Usually, the entire photoelectric sensor assembly is installed at the end of the crank or the frame part close to the rotating axis for easy wiring and maintenance.

[0175] For controllers:

[0176] (I) Signal acquisition and processing module

[0177] The controller is equipped with a special signal acquisition and processing module, which has multiple different types of input interfaces for connecting the first sensor and the second sensor in the power assist sensor group. The analog electrical signal (indicating the pedal force) transmitted by the torque sensor is converted into a digital signal through the built-in high-precision analog-to-digital converter (ADC), and before the conversion, the weak signal is amplified by the preamplifier, and the high-frequency noise and low-frequency interference signal are removed by active or passive filters to ensure the accuracy and quality of the converted digital signal.

[0178] For the pulse signal (representing the pedaling frequency) transmitted by the cadence sensor, the signal acquisition and processing module will first perform signal shaping and anti-shake processing, and use circuits such as Schmitt triggers to regularize the irregular pulse signal into a standard digital pulse signal. At the same time, it will eliminate false pulses caused by mechanical vibration, electromagnetic interference and other factors through software algorithms or hardware counters to ensure the accuracy of pedaling frequency counting.

[0179] For the drive mode judgment and instruction generation module

[0180] First drive mode related logic

[0181] When the sensor signal received by the signal acquisition and processing module corresponds to the first characteristic physical quantity (i.e., the pedaling force signal), the drive mode judgment and instruction generation module will perform calculation processing according to the pre-set first drive mode algorithm logic. The algorithm is constructed based on the linear relationship between the pedaling force measured by the torque sensor and the expected motor torque. For example, through a large number of experimental tests, it is determined that every 100N of pedaling force corresponds to 5N·m of motor torque output (the actual proportional relationship will be accurately calibrated and set according to different electric power bicycle motor performance, vehicle overall transmission efficiency and other factors).

[0182] Based on this relationship, after obtaining the digital signal corresponding to the current pedal force, the controller calculates the corresponding motor torque target value according to the built-in algorithm (which can use simple proportional calculation or more complex calculation method based on vehicle dynamics model), and then generates the first motor control instruction. This instruction contains information such as the motor's target torque, expected speed range and corresponding control parameters, and is sent to the motor control unit through the communication interface, so that the motor control unit can control the motor to output appropriate torque as required, and enter the first speed regulation mode accordingly.

[0183] Second drive mode related logic

[0184] Similarly, when the sensing signal corresponds to the second characteristic physical quantity (i.e., the pedaling frequency signal), the driving mode judgment and instruction generation module operates according to the algorithm logic of the second driving mode. In this mode, the corresponding relationship between the pedaling frequency and the motor torque is determined in advance through experiments and vehicle performance analysis. For example, a pedaling frequency of 60 times per minute is set to correspond to a motor torque output of 3N·m. As the pedaling frequency increases, the motor torque increases according to a certain proportional coefficient (e.g., for every increase of 10 times / minute in the pedaling frequency, the motor torque increases by 1N·m).

[0185] After obtaining the digital signal corresponding to the current pedaling frequency, the controller calculates the corresponding motor torque target value according to this algorithm and generates the second motor control instruction, which also covers the various parameters required for motor control and is sent to the motor control unit to control the motor to output the corresponding torque and enter the second speed regulation mode. In addition, the controller stores various parameter thresholds and control rule tables corresponding to different drive modes. These are determined after repeated testing and optimization and stored in the controller's non-volatile memory (such as Flash memory) to quickly and accurately perform judgments and instruction generation operations during actual riding.

[0186] For motor control units:

[0187] As the key intermediate link between the controller and the motor, the motor control unit plays an important role in power amplification, signal conversion and precise control of the motor's operating status.

[0188] When receiving the first motor control instruction (generated based on the pedal force signal) from the controller, the motor control unit first analyzes the parameters in the instruction, such as obtaining information such as the target torque value and the expected speed range, etc. Then, according to the type of motor (such as a brushless DC motor or a hub motor, etc.), the corresponding control strategy is used for power conversion and signal conditioning.

[0189] For brushless DC motors, the motor control unit converts the torque and speed requirements in the command into appropriate PWM (pulse width modulation) signals, and controls the input voltage and current of the motor by adjusting the duty cycle of the PWM signal, thereby achieving precise control of the motor torque and speed, so that the motor output meets the power required by the first speed regulation mode and drives the bicycle to run smoothly. In this process, the motor control unit also has closed-loop control functions such as current feedback and speed feedback, monitors the actual operating current and speed of the motor in real time, and compares them with the command requirements, and makes dynamic adjustments through internal PID (proportional-integral-differential) control algorithms to ensure that the actual operating state of the motor is consistent with the expected state, ensuring riding comfort and stability.

[0190] Similarly, when the second motor control instruction (generated based on the pedaling frequency signal) is received, the motor control unit follows a similar process and adjusts the operating state of the motor according to the parameters in the instruction through different control parameter settings (such as different PWM duty cycles corresponding to motor torque and speed requirements under different pedaling frequencies) to ensure that its output meets the power specified by the second speed regulation mode and meets the riding needs in the corresponding scenario. It also monitors and adjusts the motor operation in real time through a closed-loop control mechanism to ensure that the vehicle power output matches the crank rotation frequency.

[0191] For motors:

[0192] The motor can be a brushless DC motor, which has the advantages of high efficiency, low noise, long life and good speed regulation performance, and is suitable for electric power bicycle application scenarios. The brushless DC motor is composed of a stator, a rotor and a corresponding electronic commutation circuit.

[0193] There are multiple sets of windings wound on the stator. When the PWM signal output by the motor control unit acts on the stator windings, a rotating magnetic field can be generated inside the stator by changing the order of power-on of the windings and the current size. The rotating magnetic field interacts with the permanent magnets on the rotor to drive the rotor to rotate, thereby driving the bicycle wheels to rotate and realize the driving of the vehicle. In different speed regulation modes (the first speed regulation mode or the second speed regulation mode), the motor can accurately adjust the torque and speed according to the control signal transmitted by the motor control unit, stably and reliably provide power for the electric power-assisted bicycle, and meet the rider's power assistance needs under different riding conditions (such as changes in pedaling force or pedaling frequency).

[0194] At the same time, in order to ensure that the motor works normally in complex riding environments (such as different road conditions, different loads, etc.), the motor is designed with certain overload protection capabilities and heat dissipation measures. For example, a temperature sensor is set inside the motor. When the motor temperature is too high, the motor's operating parameters are adjusted through the controller and motor control unit to appropriately reduce the power output to prevent the motor from being damaged due to overheating. The motor housing is made of aluminum alloy with good heat dissipation performance, and the heat dissipation is accelerated through structures such as surface heat sinks to ensure the reliability and durability of the motor.

[0195] In a specific implementation, the first speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a first user state, and the second speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a second user state, and the first user state is different from the second user state:

[0196] 1. First User State and First Speed ​​Adjustment Mode

[0197] (I) Definition of the first user state and related parameters

[0198] 1. Description of user characteristics and riding habits

[0199] The first user status is mainly for people who have requirements for cycling or are relatively professional in cycling. Such riders usually have good physical fitness, strong cycling ability and certain cycling skills, and pursue a more natural riding experience that fits their own pedaling force changes. They hope to accurately control the vehicle power through their own strength adjustment during the riding process, just like riding a traditional bicycle and feeling the cycling rhythm and speed changes by relying on their own pedaling force.

[0200] When riding, they have a wide range of pedaling force, for example, the pedaling force can be flexibly changed between 100N-800N, and they can consciously adjust the pedaling force according to different road conditions (such as accelerating on flat roads, increasing force when climbing, etc.) and riding intentions (such as sprinting, maintaining a constant speed, etc.). At the same time, the pedaling frequency will also change within a relatively moderate range according to the actual situation, roughly around 40-80 times per minute, and they pay more attention to the close relationship between pedaling force and vehicle power output, hoping that the vehicle power can change instantly and naturally with the size of the pedaling force.

[0201] 2. Examples of applicable scenarios

[0202] Common application scenarios include long-distance cycling in the suburbs, participating in cycling competition training, or challenging cycling activities in the mountains. When riding long distances in the suburbs, they may adjust the pedaling force to control the speed according to the training intensity they set, sometimes speeding up for interval training, and sometimes slowing down to recover their strength; in cycling competition training, they need to accurately simulate the acceleration and overtaking operations in the competition by the size of the pedaling force; when riding in the mountains, they can flexibly increase the pedaling force according to the slope of the climb and their own physical condition to obtain enough power to climb the slope, and at the same time appropriately reduce the pedaling force when going downhill or on flat roads to enjoy a natural riding experience.

[0203] (II) Specific configuration of the first speed regulation mode

[0204] 1. Relationship between motor torque setting and pedal force

[0205] In the first speed control mode, based on the pedaling force signal detected by the torque sensor (TorqueSensor), a specially designed algorithm is used to achieve a proportional relationship between the motor torque and the pedaling force. For example, after a large number of experimental tests and vehicle power performance adjustments, a linear proportional relationship is determined, such as 8N·m of motor torque output for every 100N of pedaling force (the actual ratio will be accurately set according to factors such as the motor power and transmission efficiency of different electric-assisted bicycles).

[0206] When the rider steps on the pedal, the torque sensor measures the pedal force in real time and transmits the corresponding electrical signal to the controller. The controller calculates the corresponding motor torque target value according to this proportional relationship, generates the first motor control instruction and sends it to the motor control unit. The motor control unit then adjusts the input voltage and current of the motor according to the instruction (for example, for a brushless DC motor, PWM pulse width modulation technology is used to adjust the duty cycle of the PWM signal according to the torque target value) to accurately control the torque corresponding to the motor output, so that the vehicle power increases with the increase of pedal force, meeting the needs of professional riders for natural changes in power.

[0207] 2. Speed ​​adjustment strategy and pedal force coordination

[0208] The vehicle speed regulation works closely with the pedaling force in the first speed regulation mode. On the one hand, at the start, when the rider starts to pedal, as the pedaling force gradually increases, the motor torque is output proportionally, and the vehicle speed increases steadily and slowly. For example, when the pedaling force increases from 0 to 100N at the start, the vehicle speed may gradually increase from 0 to about 5km / h. The speed increase rate during this process can be set to increase by 0.5km / h per second based on actual tests, so that the rider has enough time to adapt to the starting process and can feel that the vehicle speed increases naturally by relying on his own pedaling force.

[0209] During normal riding, if the rider increases the pedaling force to try to accelerate, for example, the pedaling force increases from 300N to 500N, the vehicle speed will increase accordingly according to the set proportional relationship and dynamic adjustment algorithm, which may increase from 15km / h to 25km / h. The response time and change rate of the speed increase have been optimized to ensure that there will be no abrupt acceleration feeling, but a natural and smooth speed change, just like a rider accelerating by his own power when riding a traditional bicycle, giving professional riders a good control experience.

[0210] On the other hand, when the rider reduces the pedaling force to slow down, the motor torque also decreases, and the vehicle speed drops accordingly. The entire deceleration process is also natural and in line with the rider's expectations, avoiding the discomfort caused by sudden deceleration. Moreover, during the entire riding process, no matter how the vehicle speed changes, it always maintains a state that is closely related to the pedaling force and allows the rider to control it at will, meeting their requirements for riding controllability and natural riding effects.

[0211] 3. Power output response characteristics match professional riding needs

[0212] The power output response characteristics of the motor in the first speed control mode are specially designed to meet the needs of professional riders. When the rider's pedaling force changes slightly, the motor torque can be adjusted quickly and accurately, and the response time can be controlled within tens of milliseconds (specifically set according to the motor and controller performance), so that the change in vehicle power is almost synchronized with the change in pedaling force, so that the rider does not feel obvious delay, as if the vehicle has become an extension of his body power, achieving a truly natural riding effect.

[0213] For example, when climbing a hill, the rider increases the pedaling force slightly according to the slope, and the motor torque increases immediately, helping the rider to climb the hill smoothly without causing the vehicle speed to drop due to slow power response or requiring the rider to exert excessive force. When sprinting on a flat road, the rider quickly increases the pedaling force, and the motor can instantly output a large torque to push the vehicle to accelerate quickly, meeting the high requirements of professional riders for timely speed and power changes.

[0214] 2. Second User State and Second Speed ​​Adjustment Mode

[0215] (I) Second User Status Definition and Related Parameters

[0216] 1. Description of user characteristics and riding habits

[0217] The second user status is mainly suitable for people with poor physical condition or bad knee joints. Due to physical limitations, these people cannot rely on large changes in pedaling force to control vehicle power like professional cyclists. They hope that the riding process will be as easy and labor-saving as possible, reduce the burden on the knee joints and other parts, and maintain a certain speed through relatively simple and easy pedaling movements, so as to enjoy the outdoor experience brought by riding.

[0218] Their pedaling force is usually relatively small and has a narrow range of variation, generally concentrated between 50N-300N, and it is difficult to maintain a large pedaling force for a long time. In terms of pedaling frequency, they tend to maintain a relatively stable and low range, roughly around 30-60 times per minute, mainly relying on relatively regular pedaling movements to drive the vehicle, and paying more attention to the vehicle power can change smoothly with the rotation frequency of the crank without relying on large pedaling force changes, to ensure riding comfort and sustainability.

[0219] 2. Examples of applicable scenarios

[0220] Common application scenarios include leisure riding in the park, slow riding along the riverside greenway, or short-distance activities in the community. When riding leisurely in the park, they hope to enjoy the surrounding scenery in a relaxed and comfortable way, without having to pedal hard to maintain a suitable speed; when riding on the riverside greenway, they also enjoy the natural scenery, maintain a stable speed through a relatively stable pedaling frequency, and avoid physical discomfort caused by frequent adjustments in pedaling force; when doing short-distance activities in the community, they can also easily control the vehicle to meet the needs of short-distance travel and simple exercise.

[0221] (II) Specific configuration of the second speed regulation mode

[0222] 1. Relationship between motor torque setting and crank rotation frequency

[0223] In the second speed control mode, based on the crank rotation frequency signal detected by the cadence sensor (CadenceSensor), the relationship between the motor torque and the crank rotation frequency is determined by a pre-set algorithm. For example, after actual testing and vehicle performance adjustment, a crank rotation frequency of 30 times per minute is set to correspond to a motor torque output of 3N·m, and as the crank rotation frequency increases by 10 times / minute, the motor torque increases by 2N·m accordingly (the specific proportional relationship will be optimized and adjusted according to the actual vehicle situation).

[0224] When the rider steps on the pedal, the pedaling frequency sensor obtains the electrical signal corresponding to the crank rotation frequency in real time and transmits it to the controller. The controller calculates the motor torque target value according to this algorithm, generates a second motor control instruction and sends it to the motor control unit. The motor control unit then controls the motor output corresponding torque by adjusting the input parameters of the motor (such as adjusting the duty cycle of the PWM signal to change the input voltage and current for a brushless DC motor), so that the vehicle power is only related to the crank rotation frequency, and is not significantly affected by the rider's pedaling force changes, providing stable and easy riding assistance for people with poor physical condition or bad knee joints.

[0225] 2. Speed ​​regulation strategy and crank rotation frequency coordination

[0226] The speed regulation in the second speed regulation mode is mainly based on the crank rotation frequency. In the starting stage, when the rider starts to pedal at a certain crank rotation frequency, such as 30 times per minute, the motor outputs the corresponding torque to start the vehicle smoothly from 0 and slowly increase the speed to about 3km / h. The speed increase rate is relatively slow, set to about 0.3km / h per second, ensuring that the starting process is easy and comfortable without causing a large physical burden on the rider.

[0227] During normal riding, if the rider maintains a relatively stable crank rotation frequency, the vehicle speed will also be maintained in a relatively constant range. For example, when the crank rotation frequency is stable at 40 times per minute, the vehicle speed can be stabilized at around 6km / h, allowing the rider to continue riding easily. Even if the rider's pedaling force fluctuates due to physical strength and other reasons, as long as the crank rotation frequency does not change much, the vehicle speed can basically remain stable, avoiding the situation where the vehicle speed fluctuates due to unstable pedaling force, providing such users with a reliable and comfortable riding experience.

[0228] When the rider wants to speed up or slow down, he only needs to adjust the crank rotation frequency appropriately, and the motor torque and vehicle speed will change smoothly according to the set relationship. The whole process is simple and labor-saving, which meets the requirements of people with poor physical condition or bad knee joints for easy riding and ease of operation.

[0229] 3. Power output response characteristics adapt to comfortable riding needs

[0230] The power output response characteristics of the motor in the second speed regulation mode focus on comfort and stability. Since this type of user has high requirements for riding stability, the motor torque will not respond too quickly to the change in crank rotation frequency, and the response time can be set to around a few hundred milliseconds (slightly longer than the first speed regulation mode to avoid too sudden power changes), so that the vehicle power changes gradually. Even if the crank rotation frequency fluctuates slightly, the vehicle power and speed are adjusted gently, which will not make the rider feel abrupt or uncomfortable, ensuring a relaxed and comfortable riding process and reducing the physical burden.

[0231] For example, during leisure riding, when the rider slightly speeds up or slows down the crank rotation frequency, the motor torque and vehicle speed will slowly change accordingly, allowing the rider to always be in a comfortable and relaxed riding state, and to enjoy the fun of outdoor riding happily within the range allowed by physical conditions.

[0232] The electric-assisted bicycle further includes: a speed mode switching component, which is used to capture the speed mode switching action of the user to generate a speed mode switching instruction, and the controller is used to execute the switching of the sensor according to the speed mode switching instruction, and the switching of the sensor includes: switching from the first sensor to the second sensor to switch from the first speed mode to the second speed mode, or switching from the second sensor to the first sensor to switch from the second speed mode to the first speed mode. An exemplary implementation is as follows:

[0233] 1. Specific implementation of speed control mode switching component

[0234] (I) Component composition and physical form

[0235] 1. Button switch component

[0236] The speed mode switching component can be implemented in a button-type structure, which is usually installed on the handlebar of the electric power-assisted bicycle to facilitate the rider to operate during riding. For example, two buttons are set, one marked as a "professional mode" button and the other marked as a "leisure mode" button.

[0237] The "Professional Mode" button is used to switch from the second speed regulation mode (a mode based on the cadence sensor, suitable for leisure riding mode for people with poor physical condition or bad knee joints) to the first speed regulation mode (a mode based on the torque sensor, suitable for professional riders); the "Leisure Mode" button is the opposite, used to switch from the first speed regulation mode to the second speed regulation mode.

[0238] These two buttons can be made of waterproof, wear-resistant, and tactile plastic materials, and are connected to the circuit through a micro switch. The micro switch has a suitable triggering force and can generally be reliably closed under a pressing force of 1-3N, ensuring that it can be triggered by normal operation of the rider, while avoiding easy triggering due to accidental touch. The button surface can be designed with raised textures or logos, which are convenient for riders to distinguish by touch, and can be accurately operated even without looking during riding.

[0239] 2. Touch-sensitive switching components

[0240] In addition, a touch-sensitive switching component can also be used to implement the speed control mode switching function. The touch-sensitive area is integrated on both sides or on the top of the handlebar, etc., where it is easy for the rider's fingers to touch. For example, a long touch-sensitive area is set on the left side of the handlebar for switching to "professional mode", and a corresponding sensing area is set on the right side for switching to "leisure mode".

[0241] The touch-sensitive switching component works based on the principle of capacitive touch sensing. The touch-sensitive chip inside it can detect the capacitance change caused by the touch of human fingers. When the rider touches the corresponding area with his finger, the chip will convert the capacitance change into a digital signal. After being processed by the built-in signal processing circuit (including amplification, filtering, analog-to-digital conversion, etc.), it generates the corresponding speed control mode switching instruction and sends it to the controller. This touch-sensitive component has a simpler and more beautiful appearance, is more convenient to operate, and has a sense of technology. However, its cost may be slightly higher than that of the button type, and it has higher requirements for waterproof and anti-interference performance.

[0242] 2. Signal generation mechanism

[0243] 1. Push-button switch component signal generation

[0244] Taking the button-type switching component as an example, when the rider presses the "Professional Mode" button, the internal micro switch is closed, so that the circuit connected to it is turned on, and a low-level (or high-level, depending on the logic design convention of the entire circuit system, here it is assumed to be a low-level) trigger pulse signal is generated. The duration of this pulse signal can be set to tens of milliseconds (such as 30-50 milliseconds) to ensure that the controller can accurately recognize that this is a switching instruction generated by a valid button pressing operation. The signal is the speed mode switching instruction from the second speed mode to the first speed mode.

[0245] Similarly, when the "leisure mode" button is pressed, a corresponding low-level pulse signal is also generated as a switching instruction from the first speed regulation mode to the second speed regulation mode. In order to prevent false triggering caused by button jitter, an anti-shake circuit can be set in the circuit (such as using an RC filter circuit combined with a Schmitt trigger, etc.) to perform anti-shake processing on the signal generated by the button to ensure that only stable and qualified pulse signals are transmitted to the controller as valid switching instructions.

[0246] 2. Touch-sensitive switching component signal generation

[0247] For the touch-sensitive switching component, when the rider touches the corresponding sensing area with his finger, the touch-sensitive chip detects the capacitance change and converts it into an analog electrical signal. The analog signal is first amplified by the amplifier circuit to enhance the signal strength for subsequent processing, then filtered to remove noise signals such as electromagnetic interference in the environment, and finally converted into a digital signal by the analog-to-digital converter.

[0248] Different touch modes (such as short press, long press, sliding, etc.) can correspond to different command logics. For example, set the "professional mode" touch sensing area on the left side of the short press (touch time within 1-2 seconds) to generate a specific digital code signal (such as hexadecimal 0x01) as the instruction to switch to the first speed control mode; short press the "leisure mode" touch sensing area on the right side to generate a corresponding digital code signal (such as 0x02) as the instruction to switch to the second speed control mode. In this way, by utilizing the various touch operation possibilities of the touch-sensitive component, accurate speed control mode switching instructions can be flexibly generated and transmitted to the controller.

[0249] (III) Installation location and wiring considerations

[0250] 1. Reasonable installation location

[0251] Whether a button-type or touch-sensitive switching component is used, its installation position must fully consider the convenience, comfort and safety of the rider's operation. For the button-type component, the "professional mode" button is installed on the left side of the handlebar near the front of the grip position, and the "leisure mode" button is installed on the right side of the handlebar at the corresponding position. In this way, the rider can easily press the button to switch modes with his thumb without changing the handlebar grip posture during riding, and it will not affect the normal handlebar operation, ensuring riding safety.

[0252] For touch-sensitive components, the layout of the touch-sensitive area should also follow similar principles. The sensing areas used to switch to "professional mode" and "leisure mode" are set at places on both sides of the handlebar where fingers are naturally placed and easy to reach, ensuring that the rider can easily and accurately perform touch operations while riding without distracting too much attention, while avoiding interference with other functional components on the handlebar (such as brake handles, gear shift levers, etc.).

[0253] 2. Wiring design

[0254] The signal line from the speed mode switching component needs to be carefully routed to ensure the stability and reliability of signal transmission while avoiding adverse effects on other parts and the overall appearance of the bicycle. The signal line generally uses a wire with good flexibility, insulation and anti-interference ability, such as a multi-core soft wire with a shielding layer.

[0255] When laying the wires, lay them along the pre-designed wire troughs or wire tubes inside the bicycle frame, and try to avoid moving parts (such as chains, pedals, etc.) and areas that are prone to water accumulation and external force. If it is necessary to lay them in parallel with other lines outside the handlebars (such as brake lines, speed change lines, etc.), take protective and isolation measures for the signal lines to prevent electromagnetic interference and other problems from affecting the signal quality. Finally, the signal line must be accurately connected to the corresponding input interface of the controller to ensure that the speed mode switching command can be smoothly transmitted to the controller for subsequent processing.

[0256] 2. Controller processing of switching instructions and sensor switching implementation

[0257] (I) Interface and signal reception

[0258] The controller has a dedicated external signal input interface for receiving the speed mode switching instruction from the speed mode switching component. The interface type is determined by the form of the output signal of the switching component. If it is a digital pulse signal (such as a low level or high level pulse) output by a button-type component, a general digital input pin (such as a GPIO pin) can be used as the interface, and the corresponding level detection circuit and anti-shake circuit (as mentioned above, the anti-shake function is realized by hardware circuit or software algorithm) are configured to ensure accurate detection of effective pulse signals and prevent false triggering due to external interference or button jitter.

[0259] For the digital coded signal output by the touch-sensitive switching component, a communication interface with certain data receiving and parsing capabilities is required, such as a serial communication interface (SPI, I2C, etc., select the appropriate interface type based on the communication protocol of the touch-sensitive chip). The controller accurately receives and parses the speed mode switching instructions from the touch-sensitive component through the corresponding communication protocol configuration and data receiving program, ensuring that the specific instruction content corresponding to different touch operations can be identified.

[0260] (II) Instruction analysis and logical judgment

[0261] 1. Instruction recognition logic

[0262] When the controller receives the speed mode switching instruction, it will first identify and parse the instruction through the built-in program code. Taking the button switching component as an example, if a digital signal with a specific level sequence generated by pressing the corresponding "professional mode" button is received (assuming it is a low-level pulse signal lasting 30-50 milliseconds, which can be set according to the actual circuit design and programming), the instruction parsing program inside the controller will recognize it as an instruction to switch from the second speed mode to the first speed mode; similarly, if a corresponding level sequence signal corresponding to the "leisure mode" button is received, it will be judged as an instruction to switch from the first speed mode to the second speed mode.

[0263] For the command output by the touch-sensitive switching component, if a hexadecimal 0x01 digital code signal is received, the controller recognizes it as a command to switch to the first speed control mode; if a 0x02 signal is received, it is recognized as a command to switch to the second speed control mode. With such clear command recognition logic, the controller can accurately know the rider's intention to switch the speed control mode.

[0264] 2. Sensor switching control logic

[0265] Once the speed control mode switching direction is determined, the controller performs the corresponding sensor switching operation. When switching from the second speed control mode to the first speed control mode (i.e., switching from the mode based on the cadence sensor to the mode based on the torque sensor), the controller switches the sensor connection path by controlling the corresponding electronic switch (such as an analog switch, a digital multiplexer, and other circuit elements).

[0266] Specifically, the controller will first disconnect the signal connection line with the cadence sensor (CadenceSensor) so that the controller no longer receives the crank rotation frequency signal from the cadence sensor. This can be achieved by disconnecting the analog switch connecting the cadence sensor output end and the controller input end (the analog switch is controlled by the control signal output by the controller, and when switched to the first speed regulation mode, the control signal makes the analog switch in the disconnected state) or by selecting other channels through a digital multiplexer (not selecting the channel where the cadence sensor is located).

[0267] At the same time, the controller will establish a signal connection path with the torque sensor (TorqueSensor) so that the pedaling force signal detected by the torque sensor can be obtained later, such as connecting the corresponding line connecting the output end of the torque sensor and the input end of the controller (by controlling the corresponding electronic switch to close), thereby generating corresponding motor control instructions based on the pedaling force signal of the torque sensor according to the drive mode corresponding to the first speed regulation mode, controlling the motor to output torque that meets the requirements of the first speed regulation mode, achieving a natural riding effect in which the power changes with the pedaling force, and entering the first speed regulation mode suitable for professional riders.

[0268] On the contrary, when switching from the first speed regulation mode to the second speed regulation mode, the controller uses the same electronic switch control method to disconnect the connection with the torque sensor, reconnect the cadence sensor, and generate motor control instructions according to the crank rotation frequency signal of the cadence sensor and the drive mode of the second speed regulation mode, so that the motor outputs torque that adapts to the needs of leisure riding, entering the second speed regulation mode suitable for people with poor physical condition or bad knee joints.

[0269] Moreover, during the sensor switching process, the controller will also synchronously adjust the relevant signal processing parameters (such as the signal amplification factor and filter coefficient for different sensors, because different sensors have different output signal characteristics) to ensure that the sensor signals received subsequently can be accurately processed, and to ensure that the entire speed control mode switching process is carried out smoothly and reliably. For example, the pedaling force signal output by the torque sensor may be relatively weak and easily interfered by low-frequency noise. When switching to the first speed control mode, the controller will increase the signal amplification factor accordingly and adjust the filter parameters to enhance the filtering effect of low-frequency noise; and when switching to the second speed control mode and using the pedaling frequency sensor, according to the characteristics of its output pulse signal, it is adjusted to the amplification factor and filter parameters suitable for pulse signal processing to ensure signal quality and the accuracy of subsequent control.

[0270] Further, the installation position and selection of the first sensor and the second sensor, and an exemplary working principle are described as follows:

[0271] 1. About the installation position and selection of the first sensor

[0272] (I) Installed on the pedal force transmission shaft

[0273] 1. Sensor selection and principle

[0274] When the first sensor is selected as a torque sensor and installed on the pedal force transmission shaft, its working principle is based on the strain effect of the strain gauge. High-precision metal foil strain gauges are installed at appropriate positions on the surface of the shaft (usually along both sides of the axis, near the crank connection and other key stress-bearing areas). These strain gauges are very sensitive to the tiny deformation of the shaft caused by the pedaling force. When the rider applies force to the pedal, the force is transmitted to the shaft through the crank, and the shaft deforms axially or radially. The strain gauge deforms accordingly, and its resistance value changes accordingly.

[0275] By constructing a Wheatstone bridge circuit, connecting strain gauges to each arm of the bridge, and utilizing the correspondence between the unbalanced output of the bridge and the change in strain gauge resistance, the mechanical deformation is converted into an electrical signal change, thereby accurately measuring the pedaling force, that is, generating the first characteristic physical quantity (a physical quantity that represents the pedaling force and corresponds to the pressure on the pedal).

[0276] In addition, a fiber Bragg grating torque sensor can also be used. It uses the characteristics of fiber Bragg grating that is sensitive to stress and strain, and the fiber Bragg grating is pasted or embedded in a specific position inside or on the surface of the central axis. When the central axis is deformed by force, the grating period of the fiber Bragg grating changes, causing the wavelength of its reflected or transmitted light to change. By detecting the change in light wavelength, after the corresponding demodulation device and algorithm processing, the electrical signal related to the pedaling force can also be obtained, realizing the accurate measurement of the pedaling force.

[0277] When the pressure sensor is used here, a piezoresistive pressure sensor can be used, which has elastic sensitive elements such as silicon diaphragms and piezoresistors diffused on the diaphragms. When the pedal force is transmitted to the middle axis, the diaphragm is deformed by pressure, and the resistance value of the piezoresistors changes. Then, the resistance change is converted into an electrical signal through the matching measurement circuit, reflecting the pressure on the pedals.

[0278] 2. Installation methods and considerations

[0279] During installation, for strain gauge torque sensors, the center axis installation part must first be finely surface treated to ensure that the surface is flat and smooth, so that the strain gauge can be firmly attached and accurately transmit deformation. Use special glue to stick the strain gauge to the predetermined position according to strict process requirements, and then lead out the electrical signal through the wire. The wire should be routed along the center axis groove or with a special wire tube for protective wiring to avoid being pulled and damaged during the rotation of the center axis, and finally connected to the signal processing circuit board inside the frame.

[0280] The installation of the fiber grating torque sensor requires reserving appropriate mounting holes or grooves on the central axis, accurately embedding or fixing the fiber grating in the corresponding position, ensuring good stress transmission between it and the central axis. At the same time, attention should be paid to the lead-out and connection of the optical fiber, using reliable optical fiber connectors and reasonable wiring methods to prevent optical fiber breakage, ensure stable optical signal transmission, and ensure good connection with the demodulation device.

[0281] The piezoresistive pressure sensor can be installed on the side of the middle shaft or other positions where it can directly sense the pressure transmitted by the pedals through a special clamp or slot structure. It is necessary to ensure that the sensor is tightly fitted to the middle shaft, there is no loss in pressure transmission, and that the installation does not affect the normal rotation and force performance of the middle shaft. The signal output line of the sensor must also be properly wired and connected to the corresponding signal acquisition and processing circuit.

[0282] (ii) Installed at the connection between the pedal arm and the power output sprocket

[0283] 1. Sensor selection and principle

[0284] When installed here, if a stress sensor is selected as the first sensor, it works based on the piezoelectric effect of piezoelectric materials. For example, a stress sensor made of piezoelectric ceramic sheets is installed on the stress surface where the lever arm and the sprocket are connected. When the rider's pedaling force is transmitted here, the stress generated causes the piezoelectric ceramic sheet to deform. According to the piezoelectric effect, the piezoelectric ceramic will generate charges on its surface. The amount of charge is proportional to the stress. The charge signal is converted into a voltage signal through circuits such as charge amplifiers to reflect the stress generated by the pedaling force, thereby characterizing the first characteristic physical quantity, the pressure on the pedal.

[0285] The torque sensor can also be installed here. The principle is similar to that of installing it on the middle axis. It also uses strain gauges and other components to sense the deformation of the connection caused by the pedaling force, but the specific force conditions and deformation modes are different. The strain gauges here should be reasonably arranged according to the force direction and characteristics of the connection. For example, multiple strain gauges are arranged along the axial and vertical axial directions of the lever arm to form a full-bridge circuit, so as to more accurately measure the complex deformation caused by the pedaling force transmission, thereby accurately obtaining the pedaling force signal.

[0286] 2. Installation methods and considerations

[0287] For piezoelectric stress sensors, ensure that they are in full contact with the surface of the connection between the lever arm and the sprocket during installation. High-strength, high-adhesive glue such as epoxy resin can be used for pasting and fixing. At the same time, the sensor should be sealed and protected to prevent external environmental factors (such as moisture, dust, etc.) from affecting the performance of piezoelectric materials and the normal collection of charge signals. The signal output line should be routed along the lever arm wire groove or with a protective cover to avoid interference with components such as chains and sprockets, ensuring stable transmission of the signal to the subsequent processing circuit.

[0288] The torque sensor is installed here. The surface of the connection needs to be polished, cleaned and other pre-processed first, and then the strain gauge is pasted according to the designed layout plan (if a strain gauge torque sensor is used). The lead wires of the strain gauge should be arranged and fixed in an orderly manner to prevent them from being torn off or interfering with each other during the movement of the lever arm. Through reasonable wiring, they are connected to the signal conditioning and acquisition circuits in the frame to ensure that the pedal force signal can be accurately transmitted and processed.

[0289] 2. About the installation position and selection of the second sensor

[0290] (I) Installed on the pedal arm

[0291] 1. Sensor selection and principle

[0292] When the second sensor is selected as a speed sensor (cadence sensor) and installed on the pedal lever, a photoelectric sensor is often used, and its principle has been mentioned above. A code disc with evenly distributed light-transmitting and opaque stripes or holes is fixed at the end of the rotating shaft of the lever, and the code disc rotates synchronously with the lever. A light-emitting diode is set on one side of the code disc as a light source, and a phototransistor is installed at the corresponding position on the other side as a light receiving element.

[0293] When the lever arm rotates as the rider pedals, the encoder disk rotates, causing the light signal received by the phototransistor to change periodically. By detecting and counting the frequency of the light signal changes, the rotation frequency of the pedaling lever arm can be obtained, which is the second characteristic physical quantity.

[0294] An angular velocity sensor can also be installed here, for example, a micro-electromechanical system (MEMS) angular velocity sensor, which senses the angular velocity change of the lever arm when it rotates through a micro-mechanical structure (such as a vibration mass block, a detection capacitor, etc.). When the lever arm rotates, the angular velocity change will cause the micro-mechanical structure inside the sensor to produce a corresponding displacement or capacitance change, and these changes will be converted into electrical signal output through the built-in detection circuit. The electrical signal represents the angular velocity of the lever arm, and then the rotation frequency, a related physical quantity, can be converted.

[0295] When the displacement sensor is installed on the lever arm, for example, a linear variable differential transformer (LVDT) displacement sensor is used, one end of which can be fixed on the vehicle frame, and the other end can be connected to the lever arm through a connecting rod or other structure, so that when the lever arm rotates, the movable end of the sensor is driven to produce a displacement change. The LVDT changes the output induced electromotive force according to the displacement of the iron core in the winding, and obtains the displacement information related to the rotation of the lever arm by detecting the change in the electromotive force, and then calculates the rotation frequency through a certain algorithm processing.

[0296] 2. Installation location and method

[0297] For the photoelectric pedaling sensor, it is necessary to ensure that the code disk is tightly connected to the rotating shaft of the lever arm. An interference fit or a special coupling can be used to fix them to ensure that the rotation synchronization error between the two is extremely small. The light-emitting diode and the phototransistor should be installed at a suitable angle and distance. The general angle deviation is controlled within ±5°. The distance is adjusted between a few millimeters and more than ten millimeters according to the intensity of the light source and the sensitivity of the sensor. Shading and protection measures should be taken to avoid interference from external light. The installation position should ensure that there will be no collision or interference with other components during the rotation of the lever arm. The signal line is routed along the lever arm and properly fixed, and finally connected to the corresponding signal input interface of the controller.

[0298] MEMS angular velocity sensors are usually small in size and can be installed by pasting or embedding on the side of the lever arm or other relatively stable positions that can accurately sense the angular velocity of rotation. The installation plane must be parallel to the rotation plane of the lever arm to ensure the accuracy of the measurement. The signal output line of the sensor must also be well protected and wired to prevent it from being affected by external forces or electromagnetic interference, and connected to the corresponding signal processing circuit for subsequent calculations to obtain the rotation frequency information.

[0299] When installing the LVDT displacement sensor, the connection between the connecting rod, the lever arm and the movable end of the sensor should be flexible and without gap to ensure that the rotation of the lever arm can accurately drive the displacement of the movable end of the sensor. The sensor body should be firmly installed in a suitable position on the frame to avoid factors such as vibration affecting the displacement measurement accuracy. The signal line should be arranged reasonably and connected to the circuit module that can perform displacement-frequency conversion processing, so as to finally realize the detection of the rotation frequency of the pedal lever arm.

[0300] (ii) Installed on the axle power adapter

[0301] 1. Sensor selection and principle

[0302] If the speed sensor is installed on the axle power adapter, a Hall effect sensor can be used. The Hall sensor is installed at the fixed part of the axle power adapter, and several small magnets are evenly arranged on the axle. When the wheel rotates and drives the axle to rotate, the magnets on the axle pass through the Hall sensor in turn. Due to the Hall effect, the change in the magnetic field will cause the Hall sensor to generate a pulse signal. By detecting the number of pulse signals per unit time and combining parameters such as the wheel circumference, the speed of the bicycle can be calculated, which indirectly reflects the rotation frequency of the pedaling lever arm (because under normal riding conditions, there is a certain correlation between the wheel speed and the rotation frequency of the lever arm).

[0303] When the angular velocity sensor is installed here, it also works by sensing the angular velocity of the wheel shaft based on the MEMS and other technical principles. Its internal micromechanical structure generates corresponding electrical signal changes according to the angular velocity changes of the wheel shaft when it rotates. After signal processing and conversion, the value representing the angular velocity of the wheel shaft is obtained. Then, according to the transmission ratio between the wheel shaft and the pedal lever arm, the second characteristic physical quantity, the rotation frequency of the pedal lever arm, is calculated.

[0304] The displacement sensor is installed on the axle power adapter. For example, a rotary encoder type displacement sensor can be used. It works by detecting the change in the rotation angle of the axle (essentially also an angular displacement). When the axle rotates, the code disk inside the rotary encoder rotates synchronously with the axle. The angle change information of the code disk is read through photoelectric or electromagnetic induction, and converted into an electrical signal output. Then, based on the corresponding relationship between the rotation angle of the axle and the rotation frequency of the pedal arm, the rotation frequency, the target physical quantity, is obtained through algorithm processing.

[0305] 2. Installation location and method

[0306] For the Hall effect speed sensor, the relative position of the Hall sensor and the magnet on the axle should be precisely adjusted. The distance between the two is generally kept at about 2-5 mm to ensure that the magnetic field change can effectively trigger the Hall sensor to generate a clear and stable pulse signal. The Hall sensor should be firmly installed on the appropriate mounting seat of the axle power adapter to prevent position offset caused by vibration and other factors from affecting signal acquisition. Its signal line is routed along the frame wire trough or wire tube and connected to the signal input port of the controller for subsequent speed and related frequency calculations.

[0307] When installing the MEMS angular velocity sensor on the wheel axle power adapter, it is necessary to choose a relatively stable position that can accurately sense the angular velocity of the wheel axle, such as near the wheel axle bearing seat. During installation, it is necessary to ensure that the installation plane of the sensor and the wheel axle are parallel and concentric to ensure the accuracy of the angular velocity measurement. The signal line should be well protected and fixed, and connected to the corresponding signal processing circuit for data processing and frequency conversion.

[0308] The rotary encoder displacement sensor is installed on the axle power adapter. To ensure that the code disk is tightly connected to the axle, reliable fixing methods such as key connection and set screws can be used to ensure that the two rotate synchronously. At the same time, the signal line of the encoder should be reasonably wired and connected to the circuit module that can perform angle-frequency conversion processing, ultimately achieving accurate detection of the rotation frequency of the pedal lever.

[0309] 3. About speed control in different speed regulation modes

[0310] (I) Refinement of the relationship between speed and pedal force in the first speed regulation mode

[0311] In the first speed regulation mode, the speed of the electric power-assisted bicycle is set to be proportional to the pedal force borne by the pedal and has nothing to do with the rotation frequency of the pedaling force arm.

[0312] 1. Control principle and algorithm

[0313] The controller runs an algorithm based on proportional control (P control) to achieve this function. First, the first sensor (such as a torque sensor, etc.) transmits the pedal force signal (in the form of an electrical signal) corresponding to the pressure on the pedal to the controller. The controller converts the analog electrical signal into a digital signal through the built-in analog-to-digital converter (ADC), and then performs signal preprocessing, including filtering to remove noise interference, amplifying to enhance signal strength, and other operations.

[0314] Then, the calculation is performed based on the proportional coefficient relationship between the pedal force and the speed determined in advance through a large number of experimental tests and vehicle dynamics modeling. For example, after actual testing, it is determined that every 100N of pedal force corresponds to a 5km / h increase in vehicle speed (this proportional coefficient for different models will vary depending on factors such as motor power and transmission efficiency). After obtaining the digital signal value corresponding to the current pedal force, the controller calculates the corresponding target vehicle speed value according to this proportional coefficient, generates the first motor control instruction, which contains information such as the motor's target torque, expected speed range, and corresponding control parameters, and sends it to the motor control unit.

[0315] After receiving the command, the motor control unit controls the input voltage and current of the brushless DC motor by adjusting the duty cycle of the PWM (pulse width modulation) signal, thereby controlling the motor to output the corresponding torque and drive the bicycle to travel at the target speed. During the entire process, no matter how the rotation frequency of the pedal arm changes, the controller only adjusts the speed according to the pedal force, thereby achieving a natural riding effect in which the speed is proportional to the pedal force, meeting the needs of professional riders who have high riding requirements.

[0316] 2. Parameter setting and adjustment optimization

[0317] In practical applications, it is necessary to reasonably set and dynamically adjust control parameters such as the proportional coefficient according to the specific specifications of the electric-assisted bicycle (such as wheel size, motor power, battery capacity, etc.) and the riding habits of the target user group. For example, for models with larger wheels and higher motor power, the proportional coefficient can be appropriately increased, so that the vehicle speed increases faster under the same pedaling force, which is more suitable for professional riders who pursue speed; while for user groups who focus on riding comfort and hope that the speed changes are relatively smooth, the proportional coefficient can be set slightly smaller.

[0318] In addition, these control parameters can be adjusted remotely through wireless communication interfaces (such as Bluetooth modules, which can be connected to external devices such as mobile phone APPs). During riding, riders can use mobile phone APPs to conveniently adjust the proportional coefficient between pedaling force and vehicle speed according to actual road conditions (such as flat roads, climbing, downhill, etc.) and personal physical conditions to obtain the best riding experience.

[0319] (II) Refinement of the relationship between speed and rotation frequency in the second speed regulation mode

[0320] In the second speed regulation mode, it is stipulated that the speed of the electric-assisted bicycle is proportional to the rotation frequency of the pedaling force arm and has nothing to do with the pedaling force.

[0321] 1. Control principle and algorithm

[0322] The controller uses a PID (proportional-integral-differential) control algorithm based on frequency feedback to achieve this function. The second sensor (such as a pedaling frequency sensor, etc.) detects the rotation frequency of the pedaling lever in real time and transmits the corresponding electrical signal to the controller. The controller pre-processes the signal, such as shaping and counting the pulse signal from the photoelectric sensor, filtering, amplifying, and normalizing the electrical signal representing the frequency output by other types of sensors, to ensure that an accurate and stable rotation frequency signal is obtained.

[0323] Based on the relationship model between rotation frequency and speed determined in advance through experimental tests and vehicle performance analysis, for example, a rotation frequency of 30 times per minute corresponds to a vehicle speed of 3km / h, and as the rotation frequency increases by 10 times / minute, the vehicle speed increases by 2km / h (the specific proportional relationship will be calibrated and optimized according to the actual situation of the vehicle). The controller inputs the current rotation frequency signal value into the PID control algorithm module.

[0324] The PID algorithm calculates the corresponding motor control instructions based on the preset proportional gain, integral time constant, differential time constant and other parameters (these parameters are determined through system modeling, multiple experimental debugging, etc. to ensure that the vehicle speed can be accurately controlled according to the rotation frequency) and the relationship between the desired vehicle speed and the rotation frequency, and sends them to the motor control unit. The motor control unit adjusts the operating state of the motor according to the received instructions (such as changing the motor's power supply voltage, current size and commutation frequency, etc. For a brushless DC motor, precise control of these parameters can achieve different speeds and torque outputs), so that the bicycle speed and the rotation frequency of the pedaling lever maintain a predetermined proportional relationship, achieving a stable and satisfactory speed regulation function, and meeting the needs of people with poor physical condition or bad knee joints for easy and labor-saving riding.

[0325] 2. Parameter optimization and adaptability improvement

[0326] In order to make the vehicle speed control in the second speed regulation mode more accurate and stable, it is necessary to continuously optimize the parameters of the PID control algorithm. In different riding environments (such as flat roads, gentle slopes, steep slopes, etc.), a large amount of rotation frequency and vehicle speed data is collected through actual tests, and the proportional gain, integral time constant and differential time constant are fine-tuned to improve the algorithm's adaptability to different road conditions and riding states.

[0327] At the same time, taking into account the differences in pedaling habits of different riders (for example, some riders' pedaling frequency changes quickly, while others are relatively stable), an adaptive adjustment function can be set in the controller to automatically adjust the PID algorithm parameters according to the changing trend and characteristics of the rotation frequency during riding, to ensure that the vehicle speed can accurately follow the changes in the rotation frequency of the pedaling lever, providing a comfortable and stable riding experience for different riders.

[0328] Figure 2 This is a flow chart of a speed control method for an electric-assisted bicycle according to an embodiment of the present application. Figure 2 As shown, it includes:

[0329] Acquiring a sensing signal of a power assist sensor group provided on the electric power assist bicycle;

[0330] The power assist sensor group includes at least one first sensor and a second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity;

[0331] When the sensing signal corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0332] Figure 3 This is a schematic diagram of the structure of a power assist sensor group according to an embodiment of the present application. Figure 3As shown, the power assist sensor group includes at least one first sensor and at least one second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity;

[0333] When the sensing signal of the power-assisting sensor group corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

[0334] Those skilled in the art can clearly understand that, for the convenience and brevity of description, the specific working process of the described module can refer to the corresponding process in the aforementioned method embodiment, and will not be repeated here.

[0335] In the technical solution disclosed herein, the acquisition, storage and application of user personal information involved are in compliance with the provisions of relevant laws and regulations and do not violate public order and good morals.

[0336] According to an embodiment of the present disclosure, the present disclosure also provides an electronic device and a readable storage medium.

[0337] The electronic device of the present application embodiment is intended to represent various forms of digital computers, such as laptop computers, desktop computers, workbenches, personal digital assistants, servers, blade servers, mainframe computers and other suitable computers. The electronic device can also represent various forms of mobile devices, such as personal digital processing, cellular phones, smart phones, wearable devices and other similar computing devices. The components shown herein, their connections and relationships, and their functions are only used as examples, and are not intended to limit the implementation of the present disclosure described and / or required herein.

[0338] The electronic device includes a computing unit, which can perform various appropriate actions and processes according to a computer program stored in a ROM or a computer program loaded from a storage unit into a RAM. In the RAM, various programs and data required for the operation of the electronic device can also be stored. The computing unit, ROM, and RAM are connected to each other via a bus. An I / O interface is also connected to the bus.

[0339] Multiple components in an electronic device are connected to the I / O interface, including: input units, such as keyboards, mice, etc.; output units, such as various types of displays, speakers, etc.; storage units, such as disks, optical disks, etc.; and communication units, such as network cards, modems, wireless communication transceivers, etc. The communication unit allows the electronic device to exchange information / data with other devices through computer networks such as the Internet and / or various telecommunication networks.

[0340] The computing unit can be various general and / or special processing engines with processing and computing capabilities. Some examples of computing units include, but are not limited to, central processing units (CPUs), graphics processing units (GPUs), various dedicated artificial intelligence (AI) computing chips, various computing units running machine learning model algorithms, digital signal processors (DSPs), and any appropriate processors, controllers, microcontrollers, etc. The computing unit performs the various methods and processes described above, such as the intervention task generation method. For example, in some embodiments, the intervention task generation method can be implemented as a computer software program, which is tangibly contained in a machine-readable medium, such as a storage unit. In some embodiments, part or all of the computer program can be loaded and / or installed on an electronic device via a ROM and / or a communication unit. When the computer program is loaded into RAM and executed by the computing unit, one or more steps of the intervention task generation method described above can be performed. Alternatively, in other embodiments, the computing unit can be configured to perform the intervention task generation method by any other appropriate means (e.g., by means of firmware).

[0341] Various implementations of the systems and techniques described above herein can be implemented in digital electronic circuit systems, integrated circuit systems, field programmable gate arrays (FPGAs), application specific integrated circuits (ASICs), application specific standard products (ASSPs), systems on chips (SOCs), load programmable logic devices (CPLDs), computer hardware, firmware, software, and / or combinations thereof. These various implementations may include: being implemented in one or more computer programs that can be executed and / or interpreted on a programmable system including at least one programmable processor, which can be a special purpose or general purpose programmable processor that can receive data and instructions from a storage system, at least one input device, and at least one output device, and transmit data and instructions to the storage system, the at least one input device, and the at least one output device.

[0342] The program code for implementing the method of the present disclosure may be written in any combination of one or more programming languages. These program codes may be provided to a processor or controller of a general-purpose computer, a special-purpose computer, or other programmable data processing device, so that the program code, when executed by the processor or controller, enables the functions / operations specified in the flow chart and / or block diagram to be implemented. The program code may be executed entirely on the machine, partially on the machine, partially on the machine and partially on a remote machine as a stand-alone software package, or entirely on a remote machine or server.

[0343] In the context of the present disclosure, a readable storage medium may be a tangible medium that may contain or store a program for use by or in conjunction with an instruction execution system, device, or equipment. A readable storage medium may be a machine-readable signal medium or a machine-readable storage medium. A readable storage medium may include, but is not limited to, an electronic, magnetic, optical, electromagnetic, infrared, or semiconductor system, device, or device, or any suitable combination of the foregoing. More specific examples of readable storage media may include an electrical connection based on one or more lines, a portable computer disk, a hard disk, a random access memory (RAM), a read-only memory (ROM), an erasable programmable read-only memory (EPROM or flash memory), an optical fiber, a portable compact disk read-only memory (CD-ROM), an optical storage device, a magnetic storage device, or any suitable combination of the foregoing.

[0344] To provide interaction with a user, the systems and techniques described herein can be implemented on a computer having: a display device for displaying information to the user; and a keyboard and a pointing device (e.g., a mouse or trackball) through which the user can provide input to the computer. Other types of devices can also be used to provide interaction with the user; for example, the feedback provided to the user can be any form of sensory feedback (e.g., visual feedback, auditory feedback, or tactile feedback); and input from the user can be received in any form (including acoustic input, voice input, or tactile input).

[0345] The systems and techniques described herein may be implemented in a computing system that includes back-end components (e.g., as a data server), or a computing system that includes middleware components (e.g., an application server), or a computing system that includes front-end components (e.g., a user computer with a graphical user interface or a web browser through which a user can interact with implementations of the systems and techniques described herein), or a computing system that includes any combination of such back-end components, middleware components, or front-end components. The components of the system may be interconnected by any form or medium of digital data communication (e.g., a communications network). Examples of communications networks include: a local area network (LAN), a wide area network (WAN), and the Internet.

[0346] A computer system may include a client and a server. The client and the server are generally remote from each other and usually interact through a communication network. The relationship of client and server is generated by computer programs running on respective computers and having a client-server relationship with each other. The server may be a cloud server, a server of a distributed system, or a server combined with a blockchain.

[0347] It should be understood that the above-mentioned various forms of processes can be used to reorder, add or delete steps. For example, the steps recorded in this disclosure can be executed in parallel, sequentially or in different orders, as long as the desired results of the technical solution of this disclosure can be achieved, and this document is not limited here.

[0348] The above specific implementations do not constitute a limitation on the protection scope of the present disclosure. It should be understood by those skilled in the art that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent substitution and improvement made within the spirit and principle of the present disclosure shall be included in the protection scope of the present disclosure.

Claims

1. An electric power-assisted bicycle, characterized in that: include: Power assist sensor group, controller, motor control unit, motor; The power assist sensor group includes at least one first sensor and at least one second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity; The controller is used to obtain the sensor signal of the power-assisting sensor group, and when the sensor signal corresponds to the first characteristic physical quantity, generate a first motor control instruction based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensor signal corresponds to the second characteristic physical quantity, generate a second motor control instruction based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

2. An electric-assisted bicycle according to claim 1, characterized in that: The first speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a first user state, and the second speed adjustment mode is configured to be suitable for riding the electric-assisted bicycle in a second user state, wherein the first user state is different from the second user state.

3. The electric-assisted bicycle according to claim 1, characterized in that: The electric-assisted bicycle also includes: a speed mode switching component, which is used to capture the user's speed mode switching action to generate a speed mode switching instruction, and the controller is used to execute sensor switching according to the speed mode switching instruction. The sensor switching includes: switching from the first sensor to the second sensor to switch from the first speed mode to the second speed mode, or switching from the second sensor to the first sensor to switch from the second speed mode to the first speed mode.

4. The electric-assisted bicycle according to claim 1, characterized in that: The first sensor is installed on the pedal force transmission center shaft, or at the connection between the pedal force arm and the power output sprocket; and / or the second sensor is installed on the pedal force arm, or on the wheel axle power adapter.

5. The electric-assisted bicycle according to claim 1, characterized in that: The first sensor is at least one of a torque sensor, a pressure sensor, or a stress sensor; or the second sensor is at least one of a velocity sensor, an angular velocity sensor, and a displacement sensor.

6. The electric-assisted bicycle according to claim 1, characterized in that: The first sensor generates a first characteristic physical quantity by detecting the pressure exerted on the pedal, and the second sensor generates a second characteristic physical quantity by detecting the rotation frequency of the pedal lever.

7. The electric-assisted bicycle according to claim 1, characterized in that: In the first speed regulation mode, the speed of the electric assisted bicycle is proportional to the pedaling force borne by the pedal and has nothing to do with the rotation frequency of the pedaling force arm rod; in the second speed regulation mode, the speed of the electric assisted bicycle is proportional to the rotation frequency of the pedaling force arm rod and has nothing to do with the pedaling force.

8. A speed control method for an electric power-assisted bicycle, characterized in that: include: Acquire a sensing signal of a power-assist sensor group arranged on the electric power-assist bicycle, wherein the power-assist sensor group includes at least a first sensor and a second sensor, wherein the first sensor has a first sensing mode, wherein the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, wherein the second sensing mode is different from the first sensing mode, and wherein the second sensing mode enables the second sensor to detect a second characteristic physical quantity; When the sensing signal corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

9. A power assist sensor group, characterized in that: The power assist sensor group includes at least one first sensor and at least one second sensor, the first sensor has a first sensing mode, the first sensing mode enables the first sensor to detect a first characteristic physical quantity, and the second sensor has a second sensing mode, the second sensing mode is different from the first sensing mode, and the second sensing mode enables the second sensor to detect a second characteristic physical quantity; When the sensing signal of the power-assisting sensor group corresponds to the first characteristic physical quantity, a first motor control instruction is generated based on the first driving mode, so that the first motor control unit controls the torque of the motor according to the first motor control instruction and enters the first speed regulation mode accordingly; or, when the sensing signal corresponds to the second characteristic physical quantity, a second motor control instruction is generated based on the second driving mode, so that the second motor control unit controls the torque of the motor according to the second motor control instruction and enters the second speed regulation mode accordingly.

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