Bicycle assistance control method, assistance system

Abstract

The application discloses a bicycle assisting control method and an assisting system. The method comprises the following steps: acquiring a pedaling torque Th of a pedal; judging whether the pedaling torque Th falls in a preset comfortable torque interval; if the pedaling torque is lower than the preset comfortable torque interval, controlling the motor to output no torque or a torque close to zero; and if the pedaling torque falls in or exceeds the preset comfortable torque interval, controlling the motor to output a torque according to a preset assisting algorithm. Thus, the assisting control method and system provided by the application can keep the motor rotating but output almost no torque under a low-torque-demand working condition, eliminate the feeling of missing the pedal, reduce energy consumption, greatly increase the endurance, and ensure that sufficient assistance can be provided under a high-torque-demand working condition, thereby improving the riding comfort.

Description

Technical Field

[0001] This invention belongs to the field of electric bicycle technology, specifically relating to a bicycle power assist control method and power assist system. Background Technology

[0002] Electric-assisted bicycles are widely welcomed as an economical and environmentally friendly mode of transportation.

[0003] To provide more appropriate assistance to the rider, e-bikes are typically equipped with a power output control system, which adjusts the assistance by controlling the motor's output torque. During riding, the total output torque is the sum of the manual pedaling torque and the motor's output torque.

[0004] In existing technologies, to achieve assist under all operating conditions, the motor synchronously outputs torque according to a fixed assist ratio when the rider pedals. This assist algorithm can quickly reduce the rider's pedaling burden when the bicycle requires high torque. However, when the working torque requirement is low, this assist method, with the motor still outputting torque at a fixed assist ratio, consumes relatively high power. Furthermore, it creates a feeling of pedaling without power, significantly impacting the riding experience. In addition, when the battery is low, the motor continues to maintain a high power output according to the set assist ratio, causing the battery to deplete rapidly. The assist system may then suddenly shut down due to insufficient power, damaging the battery and providing a poor user experience.

[0005] Therefore, it is necessary to improve the existing technology to overcome the aforementioned defects. Summary of the Invention

[0006] Therefore, the present invention aims to solve the technical problems of high power consumption and poor riding experience in the existing power-assistance algorithms for electric bicycles.

[0007] To solve the above-mentioned technical problems, the present invention provides an automatic vehicle assistance system, comprising:

[0008] Obtain the pedal torque Th;

[0009] Determine whether the pedaling torque Th falls within the preset comfort torque range;

[0010] If the pedaling torque Th is lower than the preset comfort torque range, the control motor will not output torque or the output torque will be close to zero; if the pedaling torque Th falls within or exceeds the preset comfort torque range, the control motor will output torque according to the preset assist algorithm.

[0011] In one embodiment, the control motor outputs torque according to a preset assist algorithm, including:

[0012] The assist ratio variation coefficient a is determined based on the pedaling torque Th; wherein the assist ratio variation coefficient a is a function of the pedaling torque Th, and the value range of the assist ratio variation coefficient a is greater than or equal to 0 and less than or equal to 1.

[0013] Determine the current assist ratio D = Ds * a; where Ds is the target assist ratio;

[0014] Determine the motor output torque Tm = pedaling torque T * assist ratio D.

[0015] In one embodiment, determining the assist ratio variation coefficient a based on the pedaling torque Th includes:

[0016] Obtain the torque values ​​T1 and T2 at the two ends of the preset comfort torque range, wherein T1 is less than T2;

[0017] The functional relationship between the assist ratio variation coefficient a and the pedaling torque Th is established based on the torque values ​​T1 and T2 at the two endpoints; wherein, when the pedaling torque Th is the endpoint torque value T1, the assist ratio variation coefficient a is 0, and when the pedaling torque Th is the endpoint torque T2, the assist ratio variation coefficient a is 1.

[0018] Based on the aforementioned functional relationship and the current pedaling torque Th, determine the current assist ratio change coefficient a.

[0019] In one embodiment, the method further includes:

[0020] Receive adjustment commands for the preset comfort torque range;

[0021] Adjust the torque values ​​at both ends of the preset comfort torque range according to the adjustment command.

[0022] In one embodiment, the method further includes:

[0023] Collect cyclist cycling status data; wherein, the cyclist cycling status data includes the cyclist's heart rate and / or continuous cycling time;

[0024] The adjustment command for the preset comfort torque range is formulated based on the riding status data.

[0025] In one embodiment, the method further includes:

[0026] Get the route and remaining battery power for this ride;

[0027] The estimated power consumption for completing the cycling route is calculated according to a preset algorithm;

[0028] If the estimated power consumption is greater than the remaining battery power, the cycling route is divided into multiple segments, and each segment is marked with a difficulty level. Power consumption is estimated based on the difficulty level. The sum of the power consumption estimates for each cycling segment is equal to the remaining battery power. The power consumption estimate for a cycling segment with a higher difficulty level is greater than the power consumption estimate for a cycling segment with a lower difficulty level.

[0029] The output power of the motor corresponding to each riding route segment is controlled according to the power budget.

[0030] In one embodiment, the method further includes:

[0031] During the ride, the remaining battery power is continuously monitored, and the power budget for each riding segment is adjusted based on the obtained remaining battery power and the remaining riding route segment.

[0032] In one embodiment, the method further includes:

[0033] Get battery power data;

[0034] If the battery power data shows that the battery power is lower than a preset power threshold, the maximum set output power Pm of the motor is reduced.

[0035] In one embodiment, reducing the maximum set output power Pm of the motor includes:

[0036] The maximum set output power of the motor is controlled to gradually decrease from Pm to Pn.

[0037] Furthermore, the present invention also provides a bicycle assist system, comprising:

[0038] The central axis has two ends suitable for connection to the foot pedals;

[0039] An electric motor, connected to a transmission mechanism, is suitable for driving wheels to rotate to output electric assistance.

[0040] A torque sensor, mounted on the central axis, is used to detect the pedaling torque T applied to the central axis by the foot pedal;

[0041] The controller, electrically connected to both the torque sensor and the motor, is used for:

[0042] Obtain the pedaling torque Th;

[0043] Determine whether the pedaling torque Th falls within the preset comfort torque range;

[0044] If the pedaling torque Th is lower than the preset comfort torque range, the control motor will not output torque or the output torque will be close to zero; if the pedaling torque Th falls within or exceeds the preset comfort torque range, the control motor will output torque according to the preset assist algorithm.

[0045] The technical solution provided by this invention has the following advantages:

[0046] This invention provides a bicycle assist control method and assist system. The method acquires the pedal torque Th; determines whether the pedal torque Th falls within a preset comfortable torque range; if the pedal torque is lower than the preset comfortable torque range, the motor is controlled to not output torque or output torque close to zero; if the pedal torque falls within or exceeds the preset comfortable torque range, the motor is controlled to output torque according to a preset assist algorithm. Thus, the assist control method and system provided by this invention, under low torque demand conditions, keep the motor rotating but output almost no torque, eliminating the feeling of slipping while reducing energy consumption and greatly increasing range, while also ensuring sufficient assist under high torque demand conditions, improving riding comfort. Attached Figure Description

[0047] To more clearly illustrate the technical solutions in the embodiments of the present invention, the accompanying drawings used in the description of the embodiments will be briefly introduced below. Obviously, the accompanying drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0048] Figure 1 This is a flowchart illustrating the bicycle power assist control method provided in an embodiment of the present invention;

[0049] Figure 2 This is a graph showing the relationship between the manual pedaling torque and the total output torque under the power assist control method provided in an embodiment of the present invention.

[0050] Figure 3 This is a comparison chart of the motor output power using the power assist control method provided in an embodiment of the present invention and existing algorithms;

[0051] Figure 4 This is a comparison chart of the average motor output power using the power assist control method provided in the embodiments of the present invention and existing algorithms;

[0052] Figure 5 This is a comparison chart of the maximum motor output power obtained by using the power assist control method provided in an embodiment of the present invention and existing algorithms.

[0053] Figure 6 This is a schematic diagram of the modular structure of a bicycle assist system provided in an embodiment of the present invention. Detailed Implementation

[0054] The technical solution of the present invention will now be clearly and completely described with reference to the accompanying drawings. Obviously, the described embodiments are only some, not all, of the embodiments of the present invention. The present invention will be described in detail below with reference to the accompanying drawings and embodiments. It should be noted that, unless otherwise specified, the embodiments and features in the embodiments of the present invention can be combined with each other.

[0055] It should be noted that the terms "first," "second," etc., in the specification, claims, and drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence.

[0056] In this invention, unless otherwise stated, directional terms such as "upper," "lower," "top," and "bottom" are generally used in relation to the direction shown in the accompanying drawings, or in relation to the vertical, perpendicular, or gravitational direction of the component itself; similarly, for ease of understanding and description, "inner" and "outer" refer to the inner and outer contours of each component itself, but the above directional terms are not intended to limit this invention.

[0057] Example 1

[0058] An electric bicycle is a flexible and convenient mode of transportation, typically consisting of pedals, wheels, handlebars, and an electric assist system. The pedals are used by the rider to pedal and drive the wheels, the handlebars are used for steering and balance, and the electric assist system is connected to the wheel drive to provide electrical assistance. Specifically, the electric assist system includes a motor that applies torque to reduce the burden of pedaling when the rider manually pedals, thus enabling assisted riding.

[0059] In existing technologies, to achieve assist under all operating conditions, the motor synchronously outputs torque according to a fixed assist ratio when the rider pedals. This assist algorithm can quickly reduce the rider's pedaling burden when the bicycle requires high torque. However, when the working torque requirement is low, this assist method, with the motor still outputting torque at a fixed assist ratio, consumes relatively high power. Furthermore, it creates a feeling of pedaling without power, significantly impacting the riding experience. In addition, when the battery is low, the motor continues to maintain a high power output according to the set assist ratio, causing the battery to deplete rapidly. The assist system may then suddenly shut down due to insufficient power, damaging the battery and providing a poor user experience.

[0060] To address the aforementioned problems, this application provides a bicycle power assist control method, applied to a bicycle power assist system. Please refer to... Figure 1 As shown, this method is implemented through the following steps:

[0061] S10, Obtain the pedal torque Th;

[0062] S20. Determine whether the pedaling torque Th falls within the preset comfort torque range;

[0063] S30. If the pedaling torque Th is lower than the preset comfort torque range, the control motor will not output torque or the output torque will be close to zero; if the pedaling torque Th falls within or exceeds the preset comfort torque range, the control motor will output torque according to the preset assist algorithm.

[0064] For ease of explanation, this application applies the above method to Figure 6 The assistance system 100 shown is for illustrative purposes only and should not be construed as a limitation of this method.

[0065] Please see Figure 6 As shown, in this implementation scenario, the power assist system 100 includes a motor 101, a bottom bracket 102, a torque sensor 103, and a controller 105. The bottom bracket 102 is adapted to connect to the bicycle pedals. The torque generated by the rider pedaling is transmitted to the bottom bracket 102, which drives the wheels to rotate, thereby enabling the bicycle to be driven by human power.

[0066] A torque sensor 103 is mounted on the bottom bracket 102 to measure the torque on the bottom bracket 102, also known as the pedaling torque Th. In step S10, the "pedaling torque Th" is the torque value on the bottom bracket 102 measured by the torque sensor 103. This pedaling torque Th reflects the burden of human pedaling. It can be understood that a larger pedaling torque Th indicates a greater burden on the pedaling person, while a smaller pedaling torque Th indicates a smaller burden on the pedaling person, making riding easier.

[0067] Motor 101 is connected to the wheel via a transmission mechanism. The torque Tm output by motor 101 drives the wheel to rotate through the transmission mechanism, thereby achieving motor-assisted riding. Let the motor output torque be Tm and the total output torque be T. Then the total output torque T is equal to the sum of the motor output torque Tm and the pedaling torque Th, that is, T = Tm + Th.

[0068] When cycling, you'll encounter various road conditions, each requiring different total torque outputs (T). For example, uphill routes require a higher load and thus a larger total torque output (T), while on flat roads at higher speeds, maintaining that speed requires a smaller total torque output (T). Downhill sections, however, require virtually no torque output to reach the target speed. Using the same assist algorithm across different road conditions leads to energy waste and a poor riding experience, such as a feeling of "losing your footing."

[0069] The inventors of this application propose the concept of comfortable torque. By designing a comfortable torque range for the optimal rider experience, the riding experience is relatively easy and enjoyable when the pedaling torque is maintained within this range. Therefore, this application uses a preset comfortable torque range to determine whether the pedaling torque Th falls within this range. If the pedaling torque Th is lower than the preset comfortable torque range, the motor is controlled to not output torque or output torque close to zero, thereby saving battery energy without reducing the riding experience. If the pedaling torque Th falls within or exceeds the preset comfortable torque range, the motor is controlled to output torque Tm according to a preset assist algorithm, that is, the motor provides a certain amount of assistance. The assistance method is applied according to the preset algorithm to maintain appropriate assistance, saving battery power and extending the range while maintaining a comfortable riding experience.

[0070] The above-mentioned state of "the motor does not output torque or the output torque is close to zero" corresponds to the motor output shaft only spinning and basically no torque output.

[0071] In a specific embodiment, the two endpoints of the preset comfort torque range are denoted as T1 and T2, where T1 is less than T2. ​​The preset comfort torque range is mathematically expressed as (T1, T2). It may or may not include the endpoint values ​​T1 or T2. Experimental studies have shown that the value of T1 can be 10 N·m, and the corresponding value of T2 is 30 N·m. The values ​​of T1 and T2 can fluctuate within a certain range, such as ±3 N·m.

[0072] Specifically, when the pedal torque Th is lower than T1, it is considered that the pedal torque Th is below the preset comfort torque range; when the pedal torque Th is greater than T1 but less than T2, it is considered that the pedal torque Th falls within the preset comfort torque range; when the pedal torque Th is greater than T2, it is considered that the pedal torque Th exceeds the preset comfort torque range. The motor only provides assistance when the pedal torque Th is between T1 and T2 or exceeds T2.

[0073] Figure 2 The relationship between pedaling torque and total output torque in one embodiment is shown. As shown in Figure 2, the dashed line represents the total output torque, the solid line represents the manual pedaling torque, and the motor output torque is the difference between the dashed and solid lines. Figure 2As can be seen, the power assist control method provided in this application, when the pedaling torque is less than T1 (corresponding to stage i), the motor basically does not output torque. As the pedaling torque gradually increases from T1 to T2 (corresponding to stage ii), the motor output torque Tm increases with the increase of the pedaling torque Th. When the pedaling torque increases to T2, human pedaling has reached a critical comfort state. At this time, the motor provides output torque according to the target assist ratio Ds, reducing the burden on human riders and maintaining the riding experience. Most road conditions are typically in stage ii, where the motor provides assistance at a level lower than the target assist ratio Ds, saving battery energy consumption and maintaining riding comfort. When the pedaling torque Th is greater than T2 (corresponding to stage iii), the load is larger, and the motor output torque Tm = Th * Ds. The motor provides assistance according to the maximum set output power, ensuring sufficient assist torque for the rider. In other words, Ds is a constant, representing the maximum value of the assist ratio.

[0074] Please see Figure 3 The motor using this method is more energy-efficient than existing algorithms. When the pedaling torque is below T1, the motor outputs almost no power, resulting in zero energy consumption. During T1 and T2, the motor's output power gradually increases with the pedaling torque Th, but it provides assistance at a level generally lower than the target assist ratio Ds. This saves battery energy consumption and suppresses the feeling of missing pedal strokes, ensuring a better riding experience.

[0075] In some embodiments, the step S30 of "controlling the motor to output torque according to a preset assist algorithm" may include the following in specific implementations:

[0076] The assist ratio variation coefficient a is determined based on the pedaling torque Th;

[0077] Determine the current assist ratio D = Ds * a; where Ds is the target assist ratio;

[0078] Determine the motor output torque Tm = pedaling torque T * assist ratio D.

[0079] Specifically, the assist ratio variation coefficient 'a' is determined based on the pedaling torque. The assist ratio variation coefficient 'a' is a function of the pedaling torque Th, and the value range of the assist ratio variation coefficient 'a' is greater than or equal to 0 and less than or equal to 1.

[0080] "Target assist ratio Ds" can be understood as the upper limit of the assist ratio, that is, the maximum assist the motor can provide. Within the preset comfort torque range, the assist ratio D = Ds * a, 0 ≤ a ≤ 1, meaning the maximum assist ratio is Ds and the minimum is 0. When the pedaling torque Th is greater than T2, the assist ratio change coefficient a = 1, and the current assist ratio D = Ds.

[0081] In some embodiments, "determining the assist ratio change coefficient a" further includes the following:

[0082] Obtain the torque values ​​T1 and T2 at the two ends of the preset comfort torque range;

[0083] The functional relationship between the assist ratio variation coefficient a and the pedaling torque Th is established based on the torque values ​​T1 and T2 at the two endpoints; wherein, when the pedaling torque Th is the endpoint torque value T1, the assist ratio variation coefficient a is 0, and when the pedaling torque Th is the endpoint torque T2, the assist ratio variation coefficient a is 1.

[0084] Based on the aforementioned functional relationship and the current pedaling torque Th, determine the current assist ratio change coefficient a.

[0085] Specifically, the assist ratio variation coefficient 'a' is a linear function of the pedaling torque 'Th', and can be expressed as a = k * Th + d, where k and d are constants. When Th = T1, k * T1 + d = 0; when Th = T2, k * T2 + d = 1. Therefore, the values ​​of k and d can be determined using these two equations.

[0086] Understandably, in the corresponding i stage, that is, when the pedaling torque Th is less than T1, the assist ratio change coefficient a is zero, the assist ratio D=0, and the motor does not output torque.

[0087] The required motor assistance varies slightly depending on the type of e-bike. For example, mountain bikes, typically ridden by avid mountain riders, usually have a wider range of torque for comfortable riding. Urban e-bikes, often designed for short distances, require stronger assistance from riders. Furthermore, the desired torque range may not be entirely consistent across different riders.

[0088] To accommodate the riding needs of various bicycles and riders, in some embodiments, the method further includes:

[0089] Receive adjustment commands for the preset comfort torque range;

[0090] Adjust the torque values ​​at both ends of the preset comfort torque range according to the adjustment command.

[0091] In other words, the preset comfort torque range can be adjusted according to adjustment commands. These commands can be issued actively by the rider, for example, by setting a preset comfort torque range via a mobile app and sending it to the power assist system. Alternatively, the adjustment commands can be pre-configured by the manufacturer for different vehicle models.

[0092] The adjustment instructions can also be automatically generated. In some embodiments, the method further includes:

[0093] Collect cyclist cycling status data; wherein, the cyclist cycling status data includes the cyclist's heart rate and / or continuous cycling time;

[0094] The adjustment command for the first preset comfort torque range is formulated based on the riding status data.

[0095] In this way, the adjustment command can be adjusted according to different riding conditions of the rider. For example, if the rider has been riding for a long time and is fatigued, the comfortable torque range may no longer be suitable for the rider's initial riding condition. Or, if the rider's heart rate is detected to be high, indicating that the rider is more tired, the adjustment command will set the preset comfortable torque range to a smaller value, thereby providing a wider range of assistance and improving the riding experience.

[0096] The motor is typically powered by a battery. The remaining battery charge determines the motor's power output. When the motor's power is low, it cannot output the desired torque, potentially resulting in a situation where the destination is not reached, but the battery is already depleted, leaving the remaining distance entirely dependent on manual pedaling torque, leading to a poor user experience.

[0097] In some embodiments, the bicycle can also acquire a cycling route. For example, when a cyclist navigates via a terminal, the bicycle acquires the navigation route (i.e., the cycling route) by communicating with the terminal. When the bicycle itself is equipped with a navigation module, the navigation route is used as the cycling route when the user sets a destination through the navigation module.

[0098] To balance energy consumption throughout the cycling route, in some embodiments, the method further includes:

[0099] Get the route and remaining battery power for this ride;

[0100] The estimated power consumption for completing the cycling route is calculated according to a preset algorithm;

[0101] If the expected power consumption is greater than the remaining battery power, the cycling route is divided into multiple segments, and each segment is marked with a difficulty level. Power consumption is estimated based on the difficulty level. The sum of the power consumption estimates for each cycling segment is equal to the remaining battery power. The power consumption estimate for cycling segments with higher difficulty levels is greater than that for cycling segments with lower difficulty levels.

[0102] The bicycle controls the motor's output power according to the energy budget for each riding route segment.

[0103] The method for dividing cycling routes can be based on road condition characteristics. Route segments with consistent road condition characteristics are grouped together. For example, if a navigation route includes both continuous flat sections and mountainous sections, the continuous flat sections are divided into one cycling route segment, and the mountainous sections into another. Difficulty levels are then assigned to each route segment based on its road condition characteristics. For instance, the difficulty level of a mountainous section is higher than that of a flat section. In other words, the difficulty level of each cycling route segment is determined based on the road conditions of the route.

[0104] "Estimated power consumption" can be roughly estimated based on driving mileage and average power consumption per kilometer. The estimated power consumption may not be precise and should only be used as a preliminary reference.

[0105] When the anticipated power consumption exceeds the remaining battery power, it is assumed that the remaining power is insufficient to support the entire riding route. In this case, a power budget is calculated based on the difficulty level of each riding segment, and the bicycle is then controlled to adjust the motor's output power according to the power budget for each segment. For example, on mountainous sections, a larger power budget is set to maintain a comfortable riding experience, allowing the motor to provide greater assist torque to help the rider traverse the section more comfortably. On flat sections, where the rider's workload is lighter, less assist can be provided. In this case, the rider's comfort is not significantly compromised, and the battery maintains a continuous energy supply throughout the ride, ensuring consistent assist throughout the entire route and reducing the risk of sudden assistance interruption due to low battery power.

[0106] To further ensure continuous assistance throughout the cycling process, in some embodiments, the method further includes:

[0107] During the ride, the remaining battery power is continuously monitored, and the power budget for each riding segment is adjusted based on the obtained remaining battery power and the remaining riding route segment.

[0108] When the battery charge is too low, it is insufficient to support the power assist for the entire cycling route. In one embodiment, the method may further include:

[0109] When the estimated power consumption is greater than the remaining battery power, an alert message is issued; wherein the alert message includes the difference between the estimated power consumption and the remaining battery power, as well as a route adjustment strategy and / or charging strategy corresponding to the difference.

[0110] The aforementioned "route adjustment strategy" can be understood as identifying and recommending a more energy-efficient route to the destination. A more energy-efficient route recommendation could be a shorter cycling route or a smoother route (with fewer hills). The charging strategy could include available charging stations along the route to provide power or battery swapping services.

[0111] To extend battery range, in some embodiments, please refer to... Figure 5 The method further includes:

[0112] Get battery power data;

[0113] If the battery power data shows that the battery power is lower than the preset power threshold, reduce the maximum set output power Pm of the motor.

[0114] Specifically, Pm is the preset maximum output power of the motor when it is fully charged. When the battery level is lower than the preset charge threshold A%, the maximum output power is reduced to be lower than Pm, which limits the maximum output power of the motor. This extends the driving range by suppressing energy consumption.

[0115] In some embodiments, the step of "reducing the maximum set output power Pm of the motor" described above may include the following in a specific implementation:

[0116] The maximum set output power of the motor is controlled to gradually decrease from Pm to Pn.

[0117] The gradual reduction in power helps protect the battery, and the motor's assistance decreases continuously without abrupt interruptions, providing a smooth transition for the rider, resulting in a better riding experience and maximizing range. Please see below. Figure 4 As shown, existing algorithms do not manage motor output. When the battery level drops below B%, the battery activates low-battery protection, directly cutting off the power supply. The motor suddenly stops assisting, resulting in a poor rider experience. However, this method limits the motor's output power when the battery level drops below A%. The motor actively reduces its maximum output power when the battery level is low, allowing the remaining battery power to maintain continuous operation for a longer period, thus extending the riding range. Therefore, the method provided by this invention results in a bicycle mileage greater than that of a bicycle using existing algorithms, and the average output power is lower. Here, A% is less than B%. A% is typically taken as 20%.

[0118] The power assist control method provided in this embodiment, by setting the comfort torque range and reasonably adjusting the motor assist strategy according to the comfort torque range, can effectively improve the battery range and the rider's riding comfort experience.

[0119] The various embodiments in this specification are described in a progressive manner. The same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on describing the differences from other embodiments. Example

[0120] Please see Figure 6 The present invention also provides a bicycle power assist system 100 (hereinafter referred to as power assist system 100) for use in power-assisted bicycles. In this embodiment, the power assist system 100 includes a motor 101, a bottom bracket 102, a torque sensor 103, and a controller 105.

[0121] In practical applications, electric bicycles typically include pedals, wheels, and handlebars. There is a pair of pedals, each connected to one end of the bottom bracket 102. The torque generated when the rider pedals is transmitted to the bottom bracket 102, which in turn drives the wheels to rotate, thus enabling the bicycle to be driven by human power.

[0122] Motor 101 is connected to the wheel via a transmission mechanism. The torque output by motor 101 drives the wheel to rotate through the transmission mechanism, thus achieving motor-assisted riding. In some implementation scenarios, motor 101 is connected to the chainring, which has a chain. When the motor drives the chainring to rotate, the chainring drives the wheel to rotate via the chain to output assistance. It can be understood that the total output torque equals the sum of the human pedaling torque and the motor torque.

[0123] A torque sensor 103, mounted on the central axle 102, is used to detect the pedaling torque Th applied to the central axle 102 by the foot pedal. A controller 105 is electrically connected to both the torque sensor 103 and the motor 101. The controller 105 can receive the pedaling torque Th measured by the torque sensor 103 and generate control signals for the motor 101.

[0124] The controller 105 described in this embodiment is used to execute the assist control method provided in part 1 of the above embodiment. The bicycle assist system 100 described in this embodiment corresponds to the above assist control method. The functions of each module in the bicycle assist system 100 in this embodiment are described in detail in the corresponding method embodiments, and will not be repeated here.

[0125] Those skilled in the art will understand that embodiments of the present invention can be provided as methods, systems, servers, or computer program products. Therefore, the present invention can take the form of a completely software embodiment or an embodiment combining software and hardware aspects. Furthermore, the present invention can take the form of a computer program product embodied on one or more computer-usable storage media (including, but not limited to, disk storage and optical storage) containing computer-usable program code.

[0126] It should be noted that the units, devices, or modules described in the above embodiments can be implemented by computer chips or physical entities, or by products with certain functions. For ease of description, the above devices are described by dividing them into various modules according to their functions. Of course, in implementing this specification, the functions of each module can be implemented in one or more software and / or hardware, or the module that implements the same function can be implemented by a combination of multiple sub-modules or sub-units, etc. The device embodiments described above are merely illustrative. For example, the division of units is only a logical functional division, and there may be other division methods in actual implementation. For example, multiple units or components can be combined or integrated into another system, or some features can be ignored or not executed. Furthermore, the coupling or direct coupling or communication connection between the devices or units shown or discussed can be through some interfaces, and the indirect coupling or communication connection between devices or units can be electrical, mechanical, or other forms.

[0127] Obviously, the embodiments described above are merely some, not all, embodiments of the present invention. Based on the embodiments of the present invention, those skilled in the art can make other variations or modifications without creative effort, and all such variations or modifications should fall within the scope of protection of the present invention.

Claims

1. A bicycle assist control method characterized by, The method comprises: acquiring a pedaling torque Th of the pedals; determining whether the pedaling torque Th falls within a preset comfortable torque range; if the pedaling torque Th is lower than the preset comfortable torque range, controlling the motor to output no torque or a torque close to zero; if the pedaling torque Th falls within or exceeds the preset comfortable torque range, acquiring two end-point torque values T1 and T2 of the preset comfortable torque range, wherein T1 is less than T2; establishing a functional relationship between a power-assist ratio change coefficient a and the pedaling torque Th according to the two end-point torque values T1 and T2; wherein the power-assist ratio change coefficient a is a function of the pedaling torque Th, the value range of the power-assist ratio change coefficient a is greater than or equal to 0 and less than or equal to 1, the power-assist ratio change coefficient a is 0 when the pedaling torque Th is the end-point torque value T1, and the power-assist ratio change coefficient a is 1 when the pedaling torque Th is the end-point torque T2; determining a current power-assist ratio change coefficient a according to the functional relationship and the current pedaling torque Th; determining a current power-assist ratio D = Ds * a; wherein Ds is a target power-assist ratio; determining a motor output torque Tm = pedaling torque T * power-assist ratio D.

2. The assist control method according to claim 1, characterized by, The method further comprises: receiving an adjustment instruction of the preset comfortable torque range; adjusting the two end-point torque values of the preset comfortable torque range according to the adjustment instruction.

3. The assist control method according to claim 2, characterized by, The method further comprises: collecting rider riding state data; wherein the rider riding state data comprises a heart rate of the rider and / or a continuous riding time; formulating the adjustment instruction of the preset comfortable torque range according to the riding state data.

4. The assist control method according to claim 1, characterized by, The method further comprises: acquiring a riding route of the current ride and a remaining battery capacity; calculating a predicted consumption capacity of the riding route according to a preset algorithm; in the case that the predicted consumption capacity is greater than the remaining battery capacity, dividing the riding route into multiple segments, respectively identifying a difficulty level of each riding route segment, and respectively budgeting an electric capacity according to the difficulty level; wherein the sum of the electric capacity budget of each riding route segment is equal to the remaining battery capacity; the electric capacity budget of a riding route segment with a higher difficulty level is greater than that of a riding route segment with a lower difficulty level; controlling the output power of the motor corresponding to each riding route segment according to the electric capacity budget.

5. The assist control method according to claim 4, characterized by, The method further comprises: continuously monitoring the remaining battery capacity during the ride, and adjusting the electric capacity budget of each riding route segment according to the acquired remaining battery capacity and the remaining riding route segment.

6. The assist control method according to any one of claims 1-5, characterized by, The method further comprises: acquiring battery capacity data; if the battery capacity data shows that the battery capacity is lower than a preset capacity threshold, reducing the maximum set output power Pm of the motor.

7. The assist control method according to claim 6, characterized by, The reduction of the maximum set output power Pm of the motor comprises: controlling the maximum set output power of the motor to gradually decrease from Pm to Pn.

8. A bicycle assist system characterized by, The device comprises: a middle shaft, both ends of which are adapted to be connected with pedals; a motor connected with a transmission mechanism, adapted to drive a wheel to rotate to output electric power-assist; a torque sensor arranged on the middle shaft, used to detect a pedaling torque T applied to the middle shaft by the pedals; a controller electrically connected with the torque sensor and the motor, used to: Obtaining a pedaling torque Th of the pedal; Determining whether the pedaling torque Th falls within a preset comfortable torque range; If the pedaling torque Th is lower than the preset comfortable torque range, controlling the motor to output no torque or a torque close to zero; If the pedaling torque Th falls within or exceeds the preset comfortable torque range, obtaining two end point torque values T1 and T2 of the preset comfortable torque range, wherein T1 is less than T2; Establishing a function relationship between a change coefficient a of the assist ratio and the pedaling torque Th according to the two end point torque values T1 and T2; wherein the change coefficient a of the assist ratio is a function of the pedaling torque Th, the value range of the change coefficient a of the assist ratio is greater than or equal to 0 and less than or equal to 1, the change coefficient a of the assist ratio is 0 when the pedaling torque Th is the end point torque value T1, and the change coefficient a of the assist ratio is 1 when the pedaling torque Th is the end point torque T2; Determining a current change coefficient a of the assist ratio according to the function relationship and the current pedaling torque Th; Determining a current assist ratio D=Ds*a; wherein Ds is a target assist ratio; Determining a motor output torque Tm=T*assist ratio D.

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