Control method and device, power-assisted bicycle driving assembly and power-assisted bicycle

Abstract

The embodiment of the invention discloses a control method and device, a power-assisted bicycle driving assembly and a power-assisted bicycle. According to the embodiment of the invention, the torque detection signal is acquired through the single-side torque sensor, the torque analog signal representing the treading torque on the other side is determined based on the single-side torque detection signal, and the driving motor is controlled based on the torque detection signal and the torque analog signal when the speed of the power-assisted bicycle is in the medium-speed range, so that the driving speed of the power-assisted bicycle is improved. In the moped adopting the single-side torque sensor with lower cost, the driving motor is better controlled, smooth torque output of the motor is realized, and the use experience of the moped is improved while the cost is reduced.

Description

Technical Field

[0001] The present invention relates to the technical field of electromechanical control, and in particular to a control method, a device, a power-assisted bicycle driving component and a power-assisted bicycle. Background Art

[0002] Power-assisted bicycles, also known as electric-assisted bicycles (e-bikes), are a means of transportation that combines human riding with motor assistance. It retains the pedaling function of a traditional bicycle and is equipped with a small drive motor to provide additional power support when the rider pedals.

[0003] In order to effectively assist the rider's riding, the power-assisted bicycle needs to collect the torque of the rider's pedaling, and then determine whether the drive motor outputs a larger torque or a smaller torque according to the torque to provide assistance. Since the rider will alternately step on the two pedals during the pedaling process, a double-sided torque sensor is required to detect the pedaling torque on both sides. Double-sided torque sensors are relatively expensive. Summary of the invention

[0004] In view of this, the embodiments of the present invention provide a control method, a device, a power-assisted bicycle drive assembly and a power-assisted bicycle, hoping to better control the drive motor in a power-assisted bicycle using a low-cost single-sided torque sensor, achieve smooth motor torque output, reduce costs and improve the user experience of the power-assisted bicycle.

[0005] In a first aspect, an embodiment of the present invention provides a control method for controlling a driving motor of a power-assisted bicycle, wherein the method comprises:

[0006] Acquire a torque detection signal of a unilateral torque sensor, wherein the torque detection signal is used to characterize the pedaling torque of a pedal on one side of the power-assisted bicycle;

[0007] Acquire a speed detection signal from a speed sensor;

[0008] In response to the speed detection signal indicating that the speed of the power-assisted bicycle is within a predetermined medium speed range, a torque simulation signal is determined according to the torque detection signal of the single-side torque sensor, wherein the torque simulation signal is used to indicate the pedaling torque of the other side pedal of the power-assisted bicycle; and

[0009] The drive motor is controlled at least according to the torque detection signal and the torque simulation signal.

[0010] In a second aspect, an embodiment of the present invention provides a driving assembly for a power-assisted bicycle, the driving assembly comprising:

[0011] Drive motor;

[0012] A unilateral torque sensor, used for detecting the pedaling torque of a pedal on one side of the power-assisted bicycle;

[0013] a speed sensor for detecting the speed of the power-assisted bicycle; and

[0014] A controller is electrically connected to the drive motor, the single-sided torque sensor and the speed sensor, and is used to implement the method described in the first aspect.

[0015] In a third aspect, an embodiment of the present invention provides a power-assisted bicycle, wherein the power-assisted bicycle comprises:

[0016] The vehicle body; and

[0017] A power-assisted bicycle drive assembly according to the second aspect.

[0018] In a fourth aspect, an embodiment of the present invention provides a control device for controlling a driving motor of a power-assisted bicycle, wherein the control device comprises:

[0019] A first acquisition unit, used for acquiring a torque detection signal of a unilateral torque sensor, wherein the torque detection signal is used for representing a pedaling torque of a pedal on one side of the power-assisted bicycle;

[0020] A second acquisition unit, used for acquiring a speed detection signal of a speed sensor;

[0021] a simulation unit, for responding to the speed detection signal to indicate that the speed of the power-assisted bicycle is within a predetermined medium speed range, and determining a torque simulation signal according to the torque detection signal of the single-side torque sensor, wherein the torque simulation signal is used to indicate the pedaling torque of the pedal on the other side of the power-assisted bicycle; and

[0022] A control unit is used to control the drive motor at least according to the torque detection signal and the torque simulation signal.

[0023] In a fifth aspect, an embodiment of the present invention provides a controller, wherein the controller includes a memory and a processor, the memory is used to store one or more computer program instructions, wherein the one or more computer program instructions are executed by the processor to implement the method described in the first aspect.

[0024] In a sixth aspect, an embodiment of the present invention provides a computer-readable storage medium on which computer program instructions are stored, wherein the computer program instructions, when executed by a processor, implement the method described in the first aspect.

[0025] The embodiment of the present invention collects the torque detection signal through the single-sided torque sensor, and determines the torque simulation signal representing the pedaling torque on the other side based on the single-sided torque detection signal. When the speed of the power-assisted bicycle is within the medium speed range, the drive motor is controlled based on the torque detection signal and the torque simulation signal. Thus, in the power-assisted bicycle using the low-cost single-sided torque sensor, the drive motor can be better controlled to achieve smooth motor torque output, thereby reducing costs and improving the user experience of the power-assisted bicycle. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The above and other objects, features and advantages of the present invention will become more apparent through the following description of the embodiments of the present invention with reference to the accompanying drawings, in which:

[0027] Figure 1 is a schematic diagram of a power-assisted bicycle according to an embodiment of the present invention;

[0028] Figure 2 is a block diagram of a driving assembly of a power-assisted bicycle according to an embodiment of the present invention;

[0029] Figure 3 Schematic diagram of the principle of the change of the pedaling torque of the power-assisted bicycle according to the embodiment of the present invention;

[0030] Figure 4 is an exemplary waveform diagram of a torque detection signal according to an embodiment of the present invention;

[0031] Figure 5 is an exemplary waveform diagram of a torque detection signal and a torque simulation signal according to an embodiment of the present invention;

[0032] Figure 6 is a flow chart of a control method according to an embodiment of the present invention;

[0033] Figure 7 is a flow chart of determining a torque simulation signal according to an embodiment of the present invention;

[0034] Figure 8 is a flow chart of controlling the drive motor according to at least the torque detection signal and the torque simulation signal according to an embodiment of the present invention;

[0035] Fig. 9 is a flow chart of a control method for an implementation mode of an embodiment of the present invention;

[0036] Fig.10 is a schematic diagram of a control device according to an embodiment of the present invention;

[0037] Fig.11 is a schematic diagram of a controller according to an embodiment of the present invention. DETAILED DESCRIPTION

[0038] The present application is described below based on embodiments, but the present application is not limited to these embodiments. In the detailed description of the present application below, some specific details are described in detail. It is possible for those skilled in the art to fully understand the present application without the description of these details. In order to avoid confusing the essence of the present application, known methods, processes, flows, components and circuits are not described in detail.

[0039] In addition, persons of ordinary skill in the art will appreciate that the drawings provided herein are for illustration purposes and are not necessarily drawn to scale.

[0040] At the same time, it should be understood that in the following description, "circuit" refers to a conductive loop composed of at least one element or subcircuit through electrical connection or electromagnetic connection. When an element or circuit is said to be "connected to" another element or an element / circuit is said to be "connected between" two nodes, it can be directly coupled or connected to another element or there can be an intermediate element, and the connection between the elements can be physical, logical, or a combination thereof. On the contrary, when an element is said to be "directly coupled to" or "directly connected to" another element, it means that there is no intermediate element between the two.

[0041] Unless the context clearly requires otherwise, the words "include", "comprising" and similar words throughout the application should be interpreted as including rather than exclusive or exhaustive; that is, the meaning is "including but not limited to".

[0042] In the description of this application, it should be understood that the terms "first", "second", etc. are only used for descriptive purposes and cannot be understood as indicating or implying relative importance. In addition, in the description of this application, unless otherwise specified, the meaning of "plurality" is two or more.

[0043] The solutions described in this specification and in the examples, if they involve the processing of personal information, will be processed on the premise of having a legal basis (such as obtaining the consent of the subject of personal information, or being necessary for the performance of a contract, etc.), and will only be processed within the scope of regulations or agreements. If a user refuses to process personal information other than the necessary information for basic functions, it will not affect the user's use of basic functions.

[0044] Figure 1 Schematic diagram of a power-assisted bicycle according to an embodiment of the present invention. Figure 1As shown, the power-assisted bicycle 1 of the embodiment of the present invention includes a vehicle body 11, a battery 12 and a drive assembly 13. The vehicle body 11 includes the structural body and mechanical transmission parts of the power-assisted bicycle 1. For example, a frame, handlebars, a seat, a basket, wheels and a transmission system. The transmission system includes components such as a crankset 11a, a middle shaft, pedals, a chain and a rear flywheel. The crankset 11a includes two cranks and one or more sprockets (also called toothed discs). The pedals are respectively fixed to the ends of the cranks for the rider to place his feet and pedal. The middle shaft usually passes through the crankset 11a and the frame, fixing the crankset 11a and the frame in a relatively rotatable manner. The chain connects the sprocket and the rear flywheel, driving the rear flywheel to rotate and thereby driving the rear wheel to rotate. In some embodiments, the vehicle body 11 may also include a transmission. Figure 1 In the illustrated embodiment, the battery 12 is inserted into a housing space formed behind the frame. Optionally, the battery 12 may also be disposed inside the frame, for example, embedded in a seat tube, a down tube, or the like of the frame. The drive assembly 13 is disposed on the vehicle body 11, and is used to provide additional output torque to the transmission system in an electrically powered manner as the rider pedals, thereby saving the rider's energy consumption and achieving power assistance. The drive assembly 13 may be installed near the five-way connection of the frame (indicated by dotted lines in the figure), or may be installed on the rear wheel hub of the power-assisted bicycle 1, or, in a distributed installation manner, different components in the assembly may be disposed at different positions of the power-assisted bicycle.

[0045] Figure 2 FIG. 1 is a block diagram of a driving assembly of a power-assisted bicycle according to an embodiment of the present invention. Figure 2 As shown, the drive assembly 13 of this embodiment includes a drive motor 131, a unilateral torque sensor 132, a speed sensor 133 and a controller 134. Among them, the drive motor 131 is mechanically connected to the transmission system, and is used to output torque to the transmission system according to the control of the controller 134 to achieve power assistance. The unilateral torque sensor 132 is used to detect the pedaling torque of the pedal on one side of the power-assisted bicycle 1. The speed sensor 133 is used to detect the speed of the power-assisted bicycle. The controller 134 is electrically connected to the drive motor 131, the unilateral torque sensor 132 and the speed sensor 133. The controller 134 is used to receive the torque detection signal obtained by the unilateral torque sensor 132 and the speed detection signal obtained by the speed sensor 133 to control the drive motor 131. The torque detection signal and the speed detection signal can be implemented in various forms. In one implementation, the torque detection signal and / or the speed detection signal are continuously changing voltage signals. In another implementation, the torque detection signal and / or the speed detection signal can also be a discrete pulse signal.

[0046] A torque sensor is a device used to measure the torque (or torque) on a rotating shaft. In the field of bicycles, especially in power-assisted bicycles (E-bikes), torque sensors are widely used to detect the amount of force applied by the rider to the pedals, and adjust the auxiliary power provided by the drive motor accordingly. The torque sensor can detect the torque based on strain measurement, or based on the magnetoelastic effect, or through an optical or capacitive sensor. The embodiments of the present invention can use various types of unilateral torque sensors to detect unilateral torque. In order to detect the pedaling torque, the torque sensor can be set at the crank or in the middle axis. Regardless of the position it is set at, the unilateral torque sensor only has the function of detecting the pedaling torque on one side, and therefore, cannot detect the pedaling torque on the other side.

[0047] Figure 3 FIG. 1 is a schematic diagram showing the principle of detecting the pedaling torque of a power-assisted bicycle according to an embodiment of the present invention. Figure 3 As shown, for the two cranks 31 and 32 of the power-assisted bicycle. They both apply force to the sprocket 33 by rotating clockwise within the viewing angle shown in the figure, thereby driving the chain and the rear flywheel to rotate. The cranks 31 and 32 are alternately applied with pedaling torque. That is to say, in the process of rotating clockwise for one circle, the cranks 31 and 32 can only be applied with pedaling torque that causes them to rotate clockwise in the process from the top position a to the bottom position b. At the same time, since the positions of the cranks 31 and 32 are always relative, that is, when the crank 31 is at the top, the crank 32 is at the bottom, and vice versa. Therefore, in the entire cycle of the sprocket 33 rotating for one circle, a non-zero torque can be detected on one side of the crank 31 for half of the time, and during this period, even if a torque sensor is set on one side of the crank 32, the detected torque is zero, and in the other half of the cycle, it is just the opposite.

[0048] When a single-side torque sensor is set, an example of the torque detection signal obtained is as follows: Figure 4 In this embodiment, the torque detection signal is a continuously changing voltage signal. Take the example of a single-side torque sensor detecting the torque on the right side of a power-assisted bicycle. Figure 3 In the figure, when the right pedal (that is, the pedal represented by the embodiment in the figure) is at the bottom, the crank angle at this time is defined as 180 degrees. When the right pedal is at the top, we define the crank angle at this time as 0 degrees. Figure 4 As shown in the figure, when the crank is at 0 degrees and 180 degrees, the torque detection signal is 0, because at this time the pedaling force is perpendicular to the ground, the pedaling force is completely offset by the shaft, and no component is transmitted to the chain disc. Figure 3When moving clockwise within the right half circle (from position a to position b), the torque applied to the middle axis or crank gradually increases from 0. When the crank is at 90 degrees, that is, when the right pedal is at the front, the torque reaches its peak. Then, the torque gradually decreases due to the change in angle, and drops to zero when the crank is at 180 degrees. In the range of 180 degrees to 0 degrees, that is, Figure 3 When the crank moves clockwise within the right half circle, since the right crank is driven by the torque of the left crank, the torque detection signal detected by the right unilateral torque sensor indicates that the torque is 0. In this embodiment, the unilateral torque sensor will output a reference voltage signal V0 (for example, 4.0 volts) when the torque is zero. Figure 4 As can be seen from the exemplary waveform shown, the torque detection signal of the single-side torque sensor rises first and then falls in roughly half of the time period as the crank rotates, and remains at a lower fixed value in the adjacent other half of the time period. If the output torque of the drive motor is controlled only based on this torque detection signal that remains unchanged in a general time period, the power assistance will fluctuate, resulting in a poor user experience.

[0049] Since the cranks on the left and right sides of the power-assisted bicycle are symmetrically arranged, the torque change of the left crank is actually basically the same as the waveform of the right crank, but the time phase is staggered. That is, the torque change of the left crank should remain zero in the 0-180 degree range, increase first and then decrease in the 180 degree-0 degree range, and the change pattern is the same as the change trend of the right crank in the adjacent time period.

[0050] It should be understood that although Figure 4 The torque detection signal is a continuous signal. In some scenarios, the torque detection signal can also be a discrete signal.

[0051] Based on the above principle, in an embodiment of the present invention, a complete rise and fall cycle of the detected torque detection signal can be fitted into a predetermined waveform function with a shape of first rising and then falling. Then, the waveform function is translated on the time axis to the area where the torque detection signal represents the torque of 0, that is, translated to the interval where the torque detection signal is a fixed value, so that the torque state of the other side can be simulated, that is, a torque simulation signal is obtained. Furthermore, based on the torque detection signal representing the torque on one side and the torque simulation signal representing the torque on the other side, the complete torque change, that is, the torque parameter, can be obtained.

[0052] Figure 5 is an exemplary waveform diagram of the torque detection signal and the torque simulation signal of the embodiment of the present invention. The specific process of determining the torque simulation signal according to the torque detection signal can be as follows Figure 5As shown, the torque detection signal 51 presents a waveform with regular changes. Regular changes refer to the fact that the torque detection signal 51 first increases and then decreases in the first time period t1, and then remains at a fixed value in the second time period t2, and then repeats the regularity as riding progresses. However, it is not a strictly periodic signal, because during riding, the length of the first time period t1 and the second time period t2 will vary for different pedaling processes, and at the same time, the waveform performance in the first time period t1 will also be slightly different, for example, the peak value may be different. However, within the time period of one crank rotation, the torque will not change drastically, so the torque detection signal 51 can be fitted to a predetermined waveform function 51' in the closest first time period t1. Figure 5 In the embodiment shown, the predetermined waveform function is a sine wave, that is, one cycle of a sine wave. Then, the waveform function 51' is translated on the time axis to the second time period t2 with or without adjustment to obtain a torque simulation signal 52, which is used as a torque simulation signal representing the torque state of the other side in this time period. At the same time, the time interval in which the torque detection signal 51 is not a reference value (that is, representing that the detected torque is not 0), that is, the part of the first time period t1, is set to the reference value for the torque simulation signal. If the time length of the second time period t2 is different from the time length of the adjacent first time period t1, the waveform function 51' obtained by fitting can also be stretched or compressed on the time axis. It should be understood that the waveform function is not limited to a sine wave, but can also be a half-wave sine wave (which also shows a change rule of rising first and then falling), or a triangular wave, etc. Fitting the torque detection signal to a waveform function that is easy to express and processed by a general computing device can improve the calculation speed and required computing resources of subsequent control processing without significantly losing control accuracy.

[0053] In an optional implementation, the waveform function 51' can be obtained by fitting, for example, inputting the torque detection signal into a low-pass filter. After filtering out the high-frequency component in the torque detection signal, a waveform function 51' can be obtained, which is a sine wave in the first time period t1 and zero in the second time period t2. After necessary processing and translation, the torque simulation signal 52 can be obtained. The low-pass filter can be a hardware filter circuit set in the controller, or it can be implemented by software.

[0054] The second time period t2 can be determined in different ways. The second time period t2 can be determined according to the time interval when the torque detection signal 51 is a fixed value, or the time period with the same length as the adjacent first time period t1 can be directly determined as the second time period t2.

[0055] like Figure 5As shown, if the above processing is performed on the waveform in each first time period t1 during the continuous operation of the unilateral torque sensor, a continuously changing torque simulation signal can be obtained. Then, the torque detection signal 51 or the fitted waveform function 51' of the torque detection signal 51 is combined with the torque simulation signal on the time axis to obtain a torque parameter characterizing the torque change on both sides. Based on the torque parameter, the output torque of the driving motor of the power-assisted bicycle can be controlled more accurately.

[0056] In some other implementations, it is also possible not to perform curve fitting on the portion of the torque detection signal that is not zero, but to directly copy the portion as a torque simulation signal representing the time interval of the adjacent torque detection signal where the torque is zero.

[0057] In this embodiment, Figure 2 The speed sensor 133 shown can be implemented in various ways. For example, the speed sensor can be a Hall sensor or a light sensor for detecting the rotation speed. By detecting the rotation speed of any rotating component or wheel in the power-assisted bicycle transmission system and converting the rotation speed into the forward speed of the power-assisted bicycle, the speed detection signal can be determined. Of course, the speed sensor can also be a sensor based on positioning technology, for example, based on a satellite positioning system and / or network positioning to determine the position change of the power-assisted bicycle in real time, and calculate and determine the speed detection signal based on the position change and time information.

[0058] The controller 134 may be an integrated circuit or an electronic system with general data processing functions. The integrated circuit or the electronic system controls the drive motor 131 according to the torque detection signal and the speed detection signal by running a computer program stored in its memory. In this embodiment, the controller 134 may also be a dedicated integrated circuit or an electronic system manufactured specifically for executing the control process and method of the present application. Regardless of the form of implementation, the controller 134 controls the drive motor based on the process described below.

[0059] Figure 6 is a flow chart of a control method according to an embodiment of the present invention. The control method is used to control a driving motor of a power-assisted bicycle to provide an output torque assistance adapted to the pedaling torque of the rider. Figure 6 As shown, the control method of the embodiment of the present invention includes the following steps:

[0060] Step S100, obtaining a torque detection signal of a single-side torque sensor. The torque detection signal is used to characterize the pedaling torque of a pedal on one side of the power-assisted bicycle.

[0061] Step S200, obtaining a speed detection signal from a speed sensor.

[0062] Step S300, in response to the speed detection signal indicating that the speed of the power-assisted bicycle is in a predetermined medium speed range, a torque simulation signal is determined according to the torque detection signal of the single-side torque sensor. The torque simulation signal is used to indicate the pedaling torque of the other side pedal of the power-assisted bicycle.

[0063] In some implementations, the medium speed range is greater than 6 km / h and less than or equal to 18 km / h. This speed is the speed range that the power-assisted bicycle is most likely to be in during riding. At the same time, within this speed range, the rider has a good feeling for both speed and safety. The premise conditions related to speed are set in this embodiment to take into account that, within the low speed range, the user does not have high expectations for the power assistance of the drive motor, and at the same time, it is necessary to ensure the safety of use, while within the high speed range, the torque parameter has little effect on the output torque. Therefore, in this embodiment, only within the medium speed range, the pedaling torque on the other side will be simulated according to the torque detection signal of the unilateral torque sensor. As a result, the unnecessary calculation burden of the controller is effectively reduced.

[0064] Figure 7 FIG. 1 is a flow chart of determining a torque simulation signal according to an embodiment of the present invention. Figure 7 As shown, step S300 includes:

[0065] Step S310, fitting the part of the torque detection signal representing that the torque is not 0 into a predetermined waveform function. The predetermined waveform function first rises and then falls. Figure 5 In the example shown, the waveform function is a sine wave.

[0066] Specifically, in order to achieve the fitting of the torque detection signal to the predetermined waveform function, various different methods can be used. If the calculation amount is to be reduced, the predetermined waveform function can be determined according to the maximum value of the torque detection signal and the time length representing that the torque part is not 0. Figure 5 The maximum value of the torque detection signal in the first time period t1 and the time length of the first time period t1 are determined, and a sine wave or other predetermined waveform function with a cycle equal to the time length of the first time period t1 and an amplitude equal to the maximum value is determined as the waveform function obtained by fitting. In this way, the performance requirements required by the controller can be reduced to a certain extent, and the manufacturing cost can be further reduced.

[0067] Step S320, determining the torque simulation signal of the time interval in which the torque of the adjacent torque detection signal is zero according to the predetermined waveform function.

[0068] Specifically, Figure 5As shown, the fitted waveform function can be translated to the time interval where the torque detection signal represents a torque of 0, as the torque simulation signal corresponding to the time interval, to represent the pedaling torque on the side where the unilateral torque sensor cannot detect the torque.

[0069] Step S400: controlling the driving motor at least according to the torque detection signal and the torque simulation signal.

[0070] Figure 8 is a flow chart of controlling the drive motor according to at least the torque detection signal and the torque simulation signal according to an embodiment of the present invention. Figure 8 As shown, step S400 includes:

[0071] Step S410, determining the current torque parameter according to the torque detection signal and the torque simulation signal.

[0072] As for Figure 5 As described in the description of , by combining the torque detection signal 51 or the fitting signal 51 ′ of the torque detection signal 51 with the torque simulation signal on the time axis, a continuously changing torque parameter can be obtained.

[0073] Step S420: controlling the output torque of the driving motor according to the torque parameter and the speed detection signal.

[0074] Since the speed can actually reflect the rider's need for assistance to a certain extent, the speed detection signal needs to be considered when controlling the drive motor in the medium speed range.

[0075] Specifically, the first target output torque is determined according to the following formula: N1=k1*f-k2*v, wherein N1 is the first target output torque, f1 is the torque parameter, v1 is the speed corresponding to the speed detection signal, and k1 and k2 are predetermined weights. k1 and k2 can be predetermined. Furthermore, the drive motor can be controlled with the first target output torque as the control target. It is easy to understand that the controller 134 can control the drive motor 131 by adjusting parameters such as the bus voltage or current or the AC frequency of the drive motor 131.

[0076] In some optional implementations, in addition to controlling the output torque of the drive motor, the current limiting value of the drive current bus of the drive motor 131 can also be controlled, and the maximum current value of the drive current bus is limited to avoid the unreasonable first target torque calculated according to the target output torque, resulting in control failure. Specifically, the current limiting value of the drive current bus of the drive motor is controlled according to the speed detection signal. The higher the speed corresponding to the speed detection signal, the lower the current limiting value. For example, a linear function can be set so that the current limiting value decreases linearly with the increase of the speed detection signal. For example, when the speed of the power-assisted bicycle changes between 6-18 kilometers per hour, the current limiting value changes with the speed between 10 amperes and 3 amperes. It should be understood that other types of nonlinear functions can also be set. It should be understood that the current limiting value can also be set according to a fixed threshold.

[0077] The embodiment of the present invention collects the torque detection signal through the single-sided torque sensor, and determines the torque simulation signal representing the pedaling torque on the other side based on the single-sided torque detection signal. When the speed of the power-assisted bicycle is within the medium speed range, the drive motor is controlled based on the torque detection signal and the torque simulation signal. Thus, in the power-assisted bicycle using the low-cost single-sided torque sensor, the drive motor can be better controlled to achieve smooth motor torque output, thereby reducing costs and improving the user experience of the power-assisted bicycle.

[0078] Meanwhile, according to the embodiment of the present invention, different logics may be used to control the drive motor in a low speed range or a high speed range.

[0079] Optionally, if the speed detection signal indicates that the speed of the power-assisted bicycle is greater than zero and is within a predetermined low-speed range (for example, greater than 0 km / h and less than or equal to 6 km / h), the power-assisted bicycle is moving at a low speed. At this time, the rider may be pushing the bicycle or riding it. If the rider is in a riding state, there should be a need for assistance. If the rider is pushing the power-assisted bicycle, it may be dangerous if assistance is applied. Therefore, a torque detection signal is added as a condition for starting the drive motor, that is, if the torque detection signal indicates that the power-assisted bicycle is being positively pedaled (for example, the torque is greater than a predetermined error threshold), and the speed detection signal indicates that the speed of the power-assisted bicycle is greater than zero and is within a predetermined low-speed range, the drive motor is controlled at least according to the torque detection signal.

[0080] In one example, since the torque detection signal of the unilateral torque sensor usually has a non-zero reference value (e.g., 4.0 V), the power-assisted bicycle can be determined to be pedaled when the torque detection signal is greater than 4.0 V + 0.3 V. If the speed is greater than zero at this time, the controller 134 can control the drive motor 131 to start and output torque according to the control.

[0081] When controlling the drive motor, the drive motor may be controlled only according to the torque detection signal, for example, an output torque proportional to the torque detection signal is output, that is, the greater the pedaling force, the greater the assist force provided.

[0082] For another example, the output torque of the drive motor can also be controlled according to the torque detection signal and the speed detection signal at the same time. Specifically, the second target output torque is determined according to the following formula: N2 = k1*f2-k2*v2, where N2 is the second target output torque, f2 is the torque detection signal, v2 is the speed corresponding to the speed detection signal, and k1 and k2 are predetermined weights; the drive motor is controlled with the second target output torque as the control target.

[0083] At the same time, in the low-speed stage, the current limit value of the driving current bus of the driving motor can be controlled to be a predetermined first value, for example, the current limit value is maintained at 10 amps. The first value is usually the maximum value of the current limit value. In this way, a larger torque can be provided in time to help the vehicle speed up.

[0084] In this way, the start-up of the drive motor can be accurately controlled, and better assistance can be provided in the low-speed range.

[0085] If the speed detection signal indicates that the speed of the power-assisted bicycle is in a predetermined high-speed range (for example, greater than 18 km / h and less than or equal to 25 km / h), the pedaling torque has little or no effect on the required power-assisted output torque. If the driving motor is still controlled by referring to the torque detection signal, it may lead to a decline in the rider's experience. Therefore, in this embodiment, in response to the speed detection signal indicating that the speed of the power-assisted bicycle is in a predetermined high-speed range, the output torque of the driving motor is controlled according to the speed detection signal. That is to say, when the speed is high, the output torque of the driving motor is controlled only according to the speed detection signal, and the torque detection signal is no longer used as one of the variables. Specifically, the third target output torque is determined according to the following formula: N3=k2*v3, where N3 is the target output torque, v3 is the speed corresponding to the speed detection signal, and k2 is a predetermined weight; the driving motor is controlled with the third target output torque as the control target.

[0086] At the same time, in the low-speed stage, the current limit value of the drive current bus of the drive motor can be controlled to be a predetermined second value, for example, the current limit value is maintained at 3 amps. The second value is usually the minimum value of the current limit value. In this way, it is ensured that the drive motor will not output excessive torque at high speed, causing the vehicle to lose control.

[0087] According to national standards, the maximum speed limit of electric bicycles is 25 kilometers per hour. For power-assisted bicycles, above this speed threshold, the drive motor no longer provides power to ensure the safety of the rider. At the same time, if the rider stops pedaling or pedals in the opposite direction during riding, it means that the rider wants to slow down. At this time, the controller 134 can control the drive motor to stop outputting torque based on the torque detection signal returning to zero.

[0088] In some implementations, it is necessary to consider the problem of damage to the torque sensor during use. In some cases, if the torque detection signal exceeds a predetermined normal range (for example, a degree lower than the reference voltage or a degree higher than the reference voltage), it means that the unilateral torque sensor may be damaged. At this time, the torque detection signal has no reference value, so the controller 134 can be switched to control the drive motor only according to the speed detection signal. Alternatively, the controller 134 can also jointly control the drive motor according to the speed detection signal and other signals that are not associated with the torque detection signal.

[0089] Therefore, the control method of the embodiment of the present invention can control the driving motor using different strategies according to the speed within different speed ranges, which not only ensures the rider's experience of using the power-assisted bicycle, but also can fully protect the rider's safety. Moreover, no additional cost is required.

[0090] Fig. 9 FIG. 1 is a flow chart of a control method for implementing an embodiment of the present invention. Fig. 9 As shown, the method of this embodiment includes the following steps:

[0091] Step S901, obtaining a torque detection signal of a unilateral torque sensor, wherein the torque detection signal is used to characterize the pedaling torque of a pedal on one side of the power-assisted bicycle.

[0092] Step S902: Acquire a speed detection signal from a speed sensor.

[0093] Among them, step S901 and step S902 can be obtained by the controller from different sensors at the same time, or can be obtained in sequence in any order according to timing control.

[0094] In step S903, it is determined whether the power-assisted bicycle is being pedaled in the forward direction according to the torque detection signal. If yes, step S904 is executed; if not, step S905 is executed.

[0095] Step S904, determine the speed range of the speed detection signal. If it is in the low speed range, execute step S906; if it is in the medium speed range, execute step S907; if it is in the high speed range, execute step S909; if it is higher than the speed threshold, execute step S906.

[0096] In step S905, since it is previously determined that the power-assisted bicycle is not being pedaled or is being pedaled in the reverse direction, there is no power-assistance demand at present, and the driving motor is controlled not to output torque.

[0097] In step S906, the output torque of the drive motor is controlled according to the torque detection signal and the speed detection signal, and at the same time, the bus current limit value of the drive motor is set to a higher first value (for example, 10A).

[0098] When the speed is in the medium speed range, in step S907, a torque simulation signal is determined according to the torque detection signal of the single-sided torque sensor.

[0099] In step S908, the drive motor is controlled according to the speed detection signal, the torque detection signal and the torque simulation signal, and the current limit value is controlled to change inversely with the speed represented by the speed detection signal.

[0100] Specifically, the torque detection signal and the torque simulation signal can be combined into a continuously changing torque parameter on the time axis, and then the target output torque is calculated according to the speed detection signal and the torque parameter, and the drive motor is controlled according to the target output torque.

[0101] When the speed is in the high speed range, in step S909, the output torque of the drive motor is controlled according to the speed detection signal, and the current limit value is set to a lower second value (for example, 3A).

[0102] If the speed detection signal indicates that the speed is higher than the speed threshold, step S905 is executed, that is, the drive motor is controlled not to output torque to ensure the safety of the rider.

[0103] At the same time, the controller can further control other devices of the power-assisted bicycle, such as a warning light, a buzzer, a speaker or a vibration device, to remind the user of speeding.

[0104] The embodiment of the present invention collects torque detection signals through a single-sided torque sensor, and applies different controls according to different speed ranges. In the low-speed range, the drive motor is controlled based on the speed detection signal and the torque detection signal. In the medium-speed range, the torque simulation signal representing the pedaling torque on the other side is determined based on the single-sided torque detection signal, and the drive motor is controlled based on the speed detection signal, the torque detection signal and the torque simulation signal. In the high-speed range, the drive motor is controlled only based on the speed detection signal. Thus, in a power-assisted bicycle using a low-cost single-sided torque sensor, the drive motor is better controlled, smooth motor torque output is achieved, and the cost is reduced while improving the user experience of the power-assisted bicycle.

[0105] Fig.10 Schematic diagram of a control device according to an embodiment of the present invention. Fig.10 As shown, the control device of the embodiment of the present invention includes a first acquisition unit 101 , a second acquisition unit 102 , a simulation unit 103 and a control unit 104 .

[0106] The first acquisition unit 101 is used to acquire a torque detection signal of a single-side torque sensor, and the torque detection signal is used to represent the pedaling torque of a pedal on one side of the power-assisted bicycle.

[0107] The second acquisition unit 102 is used to acquire a speed detection signal from a speed sensor.

[0108] The simulation unit 103 is used to respond to the speed detection signal to characterize that the speed of the power-assisted bicycle is within a predetermined medium speed range, and to determine a torque simulation signal according to the torque detection signal of the single-sided torque sensor, wherein the torque simulation signal is used to characterize the pedaling torque of the other side pedal of the power-assisted bicycle.

[0109] The control unit 104 is used to control the drive motor at least according to the torque detection signal and the torque simulation signal.

[0110] The embodiment of the present invention collects the torque detection signal through the single-sided torque sensor, and determines the torque simulation signal representing the pedaling torque on the other side based on the single-sided torque detection signal. When the speed of the power-assisted bicycle is within the medium speed range, the drive motor is controlled based on the torque detection signal and the torque simulation signal. Thus, in the power-assisted bicycle using the low-cost single-sided torque sensor, the drive motor can be better controlled to achieve smooth motor torque output, thereby reducing costs and improving the user experience of the power-assisted bicycle.

[0111] Fig.11 Schematic diagram of a controller according to an embodiment of the present invention. Fig.11 As shown, Fig.11 The controller shown is a general data processing electronic device. The electronic device can be used to constitute the controller of the embodiment of the present invention. The electronic device includes a general computer hardware structure, which at least includes a processor 111 and a memory 112. Fig.11 The electronic device shown can be used as a central control device or a server or a user terminal of a vehicle in an embodiment of the present invention.

[0112] The processor 111 and the memory 112 are connected via a bus 113. The memory 112 is suitable for storing instructions or programs executable by the processor 111. The processor 111 may be an independent microprocessor or a collection of one or more microprocessors. Thus, the processor 111 executes the instructions stored in the memory 112, thereby executing the method flow of the embodiment of the present invention as described above to realize the processing of data and the control of other devices. The bus 113 connects the above-mentioned multiple components together, and at the same time connects the above-mentioned components to the display controller 114 and the display device and the input / output (I / O) device 115. The input / output (I / O) device 115 may be a mouse, a keyboard, a modem, a network interface, a touch input device, a somatosensory input device, a printer, and other devices known in the art. Typically, the input / output device 115 is connected to the system via an input / output (I / O) controller 116.

[0113] Those skilled in the art will appreciate that the embodiments of the present application may be provided as methods, devices (equipment) or computer program products. Therefore, the present application may adopt the form of a complete hardware embodiment, a complete software embodiment or an embodiment combining software and hardware. Moreover, the present application may adopt a computer program product implemented on one or more computer-readable storage media (including but not limited to disk storage, CD-ROM, optical storage, etc.) containing computer-usable program code.

[0114] The present application is described with reference to flowcharts of methods, apparatuses (devices) and computer program products according to embodiments of the present application. It should be understood that each process in the flowchart can be implemented by computer program instructions.

[0115] These computer program instructions may be stored in a computer readable memory capable of directing a computer or other programmable data processing device to operate in a specific manner, so that the instructions stored in the computer readable memory produce an article of manufacture including an instruction device that implements the process Figure 1 A function specified in a process or multiple processes.

[0116] These computer program instructions may also be provided to a processor of a general-purpose computer, a special-purpose computer, an embedded processor, or other programmable data processing device to produce a machine, so that the instructions executed by the processor of the computer or other programmable data processing device produce the instructions for implementing the process Figure 1 A device that specifies functions in a process or multiple processes.

[0117] Another embodiment of the present invention relates to a non-volatile storage medium for storing a computer-readable program, wherein the computer-readable program is used for a computer to execute part or all of the above method embodiments.

[0118] That is, those skilled in the art can understand that all or part of the steps in the above-mentioned embodiment method can be completed by specifying relevant hardware through a program, and the program is stored in a storage medium, including several instructions for a device (which can be a single-chip microcomputer, chip, etc.) or a processor (processor) to execute all or part of the steps of the method described in each embodiment of the present application. The aforementioned storage medium includes: U disk, mobile hard disk, read-only memory (ROM, Read-Only Memory), random access memory (RAM, Random Access Memory), disk or optical disk and other media that can store program codes.

[0119] The above description is only a preferred embodiment of the present application and is not intended to limit the present application. For those skilled in the art, the present application may have various modifications and variations. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. A control method for controlling a driving motor of a power-assisted bicycle, characterized in that: The method comprises: Acquire a torque detection signal of a unilateral torque sensor, wherein the torque detection signal is used to characterize the pedaling torque of a pedal on one side of the power-assisted bicycle; Acquire a speed detection signal from a speed sensor; In response to the speed detection signal indicating that the speed of the power-assisted bicycle is within a predetermined medium speed range, a torque simulation signal is determined according to the torque detection signal of the single-side torque sensor, wherein the torque simulation signal is used to indicate the pedaling torque of the other side pedal of the power-assisted bicycle; and The drive motor is controlled at least according to the torque detection signal and the torque simulation signal.

2. The method according to claim 1, characterized in that Determining the torque simulation signal according to the torque detection signal of the unilateral torque sensor includes: Fitting the portion of the torque detection signal representing that the torque is not 0 into a predetermined waveform function; and Determine the torque simulation signal of the time interval in which the adjacent torque detection signal represents a torque of 0 according to the predetermined waveform function; Wherein, the predetermined waveform function first rises and then falls.

3. The method according to claim 2, characterized in that The part of the torque detection signal representing that the torque is not 0 is fitted into a predetermined waveform function as follows: The predetermined waveform function is determined according to the maximum value of the torque detection signal and the time length representing that the torque is not zero.

4. The method according to claim 1, characterized in that: Controlling the drive motor at least according to the torque detection signal and the torque simulation signal comprises: Determine the current torque parameter according to the torque detection signal and the torque simulation signal; The output torque of the driving motor is controlled according to the torque parameter and the speed detection signal.

5. The method according to claim 4, characterized in that Controlling the output torque of the drive motor according to the torque parameter and the speed detection signal comprises: The first target output torque is determined according to the following formula: N1=k1*f1-k2*v1, wherein N1 is the first target output torque, f1 is the torque parameter, v1 is the speed corresponding to the speed detection signal, and k1 and k2 are predetermined weights; The drive motor is controlled with the first target output torque as a control target.

6. The method according to claim 4, characterized in that Controlling the drive motor at least according to the torque detection signal and the torque simulation signal further comprises: The current limiting value of the driving current bus of the driving motor is controlled according to the speed detection signal, wherein the higher the speed corresponding to the speed detection signal is, the lower the current limiting value is.

7. The method according to claim 1, characterized in that The method further comprises: In response to the torque detection signal indicating that the power-assisted bicycle is pedaled, and the speed detection signal indicating that the speed of the power-assisted bicycle is greater than zero and is in a predetermined low speed range, the drive motor is controlled at least according to the torque detection signal.

8. The method according to claim 7, characterized in that Controlling the drive motor at least according to the torque detection signal comprises: The output torque of the driving motor is controlled according to the torque detection signal and the speed detection signal.

9. The method according to claim 8, characterized in that Controlling the output torque of the drive motor according to the torque detection signal and the speed detection signal comprises: The second target output torque is determined according to the following formula: N2=k1*f2-k2*v2, wherein N2 is the second target output torque, f2 is the torque detection signal, v2 is the speed corresponding to the speed detection signal, and k1 and k2 are predetermined weights; The drive motor is controlled with the second target output torque as a control target.

10. The method according to claim 9, characterized in that Controlling the drive motor at least according to the torque detection signal further comprises: The current limiting value of the driving current busbar of the driving motor is controlled to be a predetermined first value.

11. The method according to claim 1 or 7, characterized in that: The method further comprises: In response to the speed detection signal indicating that the speed of the power-assisted bicycle is within a predetermined high speed range, the output torque of the driving motor is controlled according to the speed detection signal.

12. The method according to claim 11, characterized in that Controlling the driving motor according to the speed detection signal comprises: The third target output torque is determined according to the following formula: N3=k2*v, wherein N3 is the third target output torque, v3 is the speed corresponding to the speed detection signal, and k2 is a predetermined weight; The drive motor is controlled with the third target output torque as a control target.

13. The method according to claim 1, characterized in that The method further comprises: In response to the torque detection signal exceeding a predetermined normal range, the drive motor is controlled according to the speed detection signal.

14. The method according to claim 1, characterized in that The method further comprises: In response to the speed detection signal indicating that the speed of the power-assisted bicycle exceeds a speed threshold, or in response to the torque detection signal indicating that the pedal stops pedaling or rotates in the reverse direction, the drive motor is controlled to stop outputting torque.

15. A driving assembly for a power-assisted bicycle, characterized in that: The drive assembly comprises: Drive motor; A unilateral torque sensor, used for detecting the pedaling torque of a pedal on one side of the power-assisted bicycle; a speed sensor for detecting the speed of the power-assisted bicycle; and A controller is electrically connected to the drive motor, the single-sided torque sensor and the speed sensor, and is used to implement the method described in any one of claims 1-14.

16. A power-assisted bicycle, characterized in that: The power-assisted bicycle comprises: The vehicle body; and The drive assembly of the power-assisted bicycle according to claim 15.

17. A control device for controlling a driving motor of a power-assisted bicycle, characterized in that: The control device comprises: A first acquisition unit, used for acquiring a torque detection signal of a unilateral torque sensor, wherein the torque detection signal is used for representing a pedaling torque of a pedal on one side of the power-assisted bicycle; A second acquisition unit, used for acquiring a speed detection signal of a speed sensor; a simulation unit, for responding to the speed detection signal to indicate that the speed of the power-assisted bicycle is within a predetermined medium speed range, and determining a torque simulation signal according to the torque detection signal of the single-side torque sensor, wherein the torque simulation signal is used to indicate the pedaling torque of the pedal on the other side of the power-assisted bicycle; and A control unit is used to control the drive motor at least according to the torque detection signal and the torque simulation signal.

18. A controller, characterized in that: The controller comprises a memory and a processor, wherein the memory is used to store one or more computer program instructions, wherein the one or more computer program instructions are executed by the processor to implement the method according to any one of claims 1-14.

19. A computer-readable storage medium storing computer program instructions, characterized in that: When the computer program instructions are executed by a processor, the method according to any one of claims 1 to 14 is implemented.

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