Method for automatically preventing a bicycle from rolling backwards on a slope, control device, computer program product, computer-readable medium, bicycle
Patent Information
- Application Number
- EP2022798083
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2022-09-29
- Publication Date
- 2025-08-06
AI Technical Summary
Bicycles with electric drives, such as e-bikes and eMTBs, pose a safety risk when stopping on an incline due to the potential for rolling back if the brake is not applied in time, especially for inexperienced riders.
A method that determines the current inclination angle and output speed of the bicycle, comparing them to threshold values, and increases the motor torque of the electric motor until a holding torque is reached to prevent rolling back, using sensors and a control device connected to the electric drive system to automatically engage when necessary.
Enhances safety by preventing the bicycle from rolling back on inclines, providing assistance to the rider when stopping on steep terrain, thereby reducing the risk of accidents.
Smart Images
Figure 1.1
Abstract
Description
[0001] Method for automatically preventing a bicycle from rolling back on an incline, control device, computer program product, computer-readable medium, bicycle
[0002] The invention relates to a method for automatically preventing a bicycle from rolling back on an incline, a control device, a computer program product, a computer-readable medium, and a bicycle.
[0003] Bicycles with electric (auxiliary) drive, such as e-bikes and pedelecs, are enjoying increasing popularity. Sporty e-mountain bikes (eMTBs) are also in use. However, if a cyclist stops on an incline, the bike can roll backward if the brakes are not applied in time. This poses a safety risk, especially for inexperienced riders.
[0004] From DE 10 2004 035 089 A1 a braking system with rollback protection for electro-hybrid powered vehicles is known.
[0005] The invention is based on the object of increasing the safety of a rider when stopping a bicycle on an incline. This object is achieved by a method for automatically preventing a bicycle from rolling back on an incline, having the features of claim 1, a control device having the features of claim 4, a computer program product having the features of claim 6, a computer-readable medium having the features of claim 7, and a bicycle having the features of claim 8. Further developments are contained in the subclaims and will become apparent from the following description.
[0006] In methods for automatically preventing a bicycle from rolling back on an incline, the bicycle having a pedal crank unit and an electric drive system with at least one electric motor, a current inclination angle and a current output speed of the bicycle are first determined. The current inclination angle is compared to an inclination angle threshold. The current output speed is compared to an output speed threshold. If the current inclination angle exceeds the inclination angle threshold and if the current output speed exceeds the output speed threshold, a motor torque of the at least one electric motor is increased until a holding torque is reached.
[0007] The term bicycle refers to all vehicles that have both an electric (auxiliary) drive and a muscle-powered drive, whereby the bicycle can be powered either purely by muscle power or purely electrically, or in hybrid mode both by muscle power and electrically. In each case, the bicycle has a pedal crank unit and an electric drive system with at least one electric motor. The bicycle can also include a bicycle transmission, which can be, for example, a multi-speed planetary transmission or a CVT transmission or similar. The bicycle transmission can then be operatively connected to the electric drive system. Furthermore, the bicycle transmission can be operatively connected to the pedal crank unit. The bicycle transmission can be designed as a bottom bracket transmission or as a hub gear.The bicycle can, for example, be designed as an e-bike, (S-)pedelec, eMTB, cargo bike, velomobile or other suitable micromobility vehicle.
[0008] The procedure can be activated by the rider during the bicycle's ferry operation, either if they require assistance when stopping the bicycle on an incline, or the procedure can be permanently active, so that it is automatically performed every time the bicycle is stopped on an incline. The procedure can also be deactivated by the rider if they no longer require assistance.
[0009] In a first step of the method, the current angle of inclination and the current output speed of the bicycle are determined. The angle of inclination of the bicycle is a measure of the steepness of the gradient of a route traveled by the bicycle. The angle of inclination is determined using a sensor, for example using a bicycle's own angle of inclination sensor or a sensor that is part of an external unit, for example a mobile device such as a smartphone, smartwatch, fitness tracker, or similar. In the same step, the current output speed is determined. The output speed is a measure of whether and to what extent the bicycle is rolling backwards. The output speed can be measured, for example, from a non-driven wheel of the bicycle. Alternatively, the output speed can be measured from a driven wheel of the bicycle. The output speed is determined using a sensor, for example using a bicycle's own speed sensor.Alternatively, the output speed can be determined using a calculation model from other sensor-recorded values.
[0010] The sensor data is transmitted to a control unit on the bicycle. For this purpose, the control unit is connected to the corresponding sensors via a signal-effective connection. A signal-effective connection is such that data and signal exchange is possible between the connection partners. For this purpose, each connection partner has a corresponding interface. The data and signal transmission can be either wired or wireless. The control unit and the corresponding sensors therefore have interfaces that enable such a connection. If the sensor data from the external unit is to be used, data and signals are exchanged between the external unit and the bicycle's control unit, for example via a radio connection or by means of wired communication.
[0011] In a subsequent second step, the current inclination angle is compared with the inclination angle threshold. This determines whether the bicycle is on a steep or moderate incline or decline. The inclination angle threshold is stored in a memory device in the bicycle's control unit. The inclination angle threshold is preferably stored at the factory. For example, the inclination angle threshold can be 2°, 5°, 10°, 15°, or even more than 15°.
[0012] The term "threshold" or "threshold value" does not refer to a global limit that physically cannot be exceeded or undercut. Rather, it is a specific value set by a user. All values are to be understood as including tolerances. If the current inclination angle exceeds the inclination angle threshold, the procedure continues. If this is not the case, the procedure is terminated. The procedure is therefore only used for gradients that have a certain gradient, which is determined by the inclination angle threshold.
[0013] In a third step of the method, which follows the second step, the current output speed is compared with the output speed threshold. This determines whether the bicycle is rolling back, i.e., moving in the opposite direction of travel. The output speed threshold is stored in the memory of the bicycle's control unit. The output speed threshold is preferably stored at the factory. If the current output speed exceeds the output speed threshold, the method continues. If this is not the case, the method is terminated.
[0014] Finally, if the current tilt angle exceeds the tilt angle threshold and the current output speed exceeds the output speed threshold, the motor torque of at least one electric motor is increased until a holding torque is reached. In other words, the motor power is automatically increased until the bike begins to roll back. This supports the cyclist who doesn't brake at all or brakes too late on the incline. This represents a significant safety advantage for the cyclist when rolling back on steep terrain.
[0015] According to a further embodiment, the current crank torque of the bicycle is additionally determined. This preferably occurs simultaneously with the determination of the current tilt angle and the current output speed. The crank torque is determined by a sensor and transmitted to the bicycle's control unit. The crank torque is a measure of the muscle power exerted by the rider, which they transmit to the pedal crank unit via the pedals.
[0016] Subsequently, in a fourth step of the process, which follows the third step, the current crank torque is compared with the holding torque. If the current crank torque falls below the holding torque, the motor torque of at least one electric motor is increased until a holding torque is reached. This performs an additional check, but the result of the process remains the same. If the current crank torque exceeds or reaches the holding torque, the process is terminated. In this case, the rider exerts sufficient muscle power to prevent the bike from rolling backward.
[0017] According to a further embodiment, the engine torque is continuously controlled depending on the current output speed and the current inclination angle. In other words, the current output speed is continuously compared with the output speed threshold, and the current inclination angle is continuously compared with the inclination angle threshold, so that the method is permanently active.
[0018] A control device for a bicycle is signal-connectable to an electric drive system of the bicycle, and the control device comprises means for executing the method already described in the previous description. The control device can be embodied, for example, as a domain ECU or as an ECU.
[0019] When used in a bicycle, the control unit is connected to the electric drive system, or more precisely, to the actuators of the electric drive system, via a signal-effective connection, allowing the control unit to control the actuators. The control unit can therefore request an increase in motor power and thus an increase in motor torque. Furthermore, the control unit can detect the current torque.
[0020] If the control device is used in a bicycle, it is additionally connected to at least one sensor in a signal-effective manner. The control device receives data from the sensors, for example, on the current angle of inclination or the current output torque or, if applicable, the current crank torque. For example, the control device can be connected to a torque sensor, an inclination angle sensor and / or a mobile device in a signal-effective manner. If the control device is connected to the mobile device, the mobile device can receive data and signals from the mobile device that the sensors present in the mobile device detect. For example, the control device can use the inclination angle data, the speed data, the GPS data, or similar data from the mobile device.
[0021] A computer program product comprises instructions which, when the program is executed by the control device already described, cause the control device to carry out the method already described.
[0022] A computer-readable medium comprises instructions that, when executed by the previously described control device, cause it to carry out the previously described method. The computer-readable medium can be embodied, for example, as a data storage device or as a downloadable data stream.
[0023] The bicycle has the electric drive system and the previously described control device, with the electric drive system being signal-effectively connected to the control device. The control device can thus control the actuators of the electric drive system, so that an increase in motor torque can be requested. The bicycle can therefore execute the previously described method for automatically preventing the bicycle from rolling backward on an incline.
[0024] The bicycle also features a pedal crank unit. The electric drive system includes at least one electric motor and an electrical energy storage unit.
[0025] The bicycle also includes the bicycle transmission. Both the pedal crank unit and the electric drive system are connected to the bicycle transmission. Furthermore, the bicycle includes several sensors that are connected to the control device for signal transmission, e.g., torque sensors, tilt angle sensors, and / or a mobile device. Embodiments of the invention are illustrated in the figures. In detail:
[0026] Fig. 1 is a schematic representation of a bicycle according to an embodiment,
[0027] Fig. 2 is a schematic representation of a process sequence for the driving situation from Fig. 1 .
[0028] Fig. 1 shows a schematic representation of a bicycle 1 according to an exemplary embodiment. The bicycle 1 is designed as an e-bike or pedelec, or in particular as an eMTB. The bicycle 1 has a pedal crank unit 6, of which only one pedal 4 is shown for clarity. The bicycle 1 also has an electric drive system 3, the electric motor of which can be arranged, for example, in the region of the bottom bracket. The electric drive system 3 has an electrical energy storage device 5 that is connected to the electric motor. The energy storage device 5 can supply the electric motor with electrical energy (motor operation) or can be supplied with electrical energy by means of the electric motor (generator operation).
[0029] The bicycle 1 also has a bicycle transmission 2. The bicycle transmission 2 is designed as a bottom bracket transmission. The bicycle transmission 2 is operatively connected to the electric drive system 3 and the pedal crank unit 6. The bicycle 1 can therefore be powered either purely by muscle power or purely by electricity, or both by muscle power and electricity.
[0030] The bicycle 1 has a control device 20 that is signal-effectively connected to the electric drive system 3, more precisely to the actuators of the electric drive system 3. The control device 20 can therefore control the electric drive system 3.
[0031] In addition, the bicycle 1 has several sensors that are signal-effectively connected to the control device 20. The bicycle 1 has an inclination angle sensor 21 that is configured to determine the current inclination angle of the bicycle 1. The inclination angle sensor 21 transmits this value to the control device 20, so that, based on the inclination angle values, it can be determined whether the bicycle 1 is on a steep incline 7.
[0032] The bicycle 1 has a speed sensor 22 configured to determine the current output speed of the bicycle 1. The speed sensor 22 transmits this value to the control device 20. This allows it to be determined whether the bicycle 1 is rolling backward due to the incline 7 in the opposite direction to the direction of travel, which is represented by the block arrow.
[0033] The bicycle 1 may have a crank torque sensor 23 configured to determine the current crank torque of the bicycle 1. The crank torque sensor 23 transmits this value to the control device 20.
[0034] Based on the sensor-determined values, an automated prevention of the bicycle 1 rolling back on the incline 7 can be carried out, as shown in the process flow diagram in Fig. 2.
[0035] Fig. 2 shows a schematic representation of a method sequence for the driving situation from Fig. 1. In the process flow diagram of the method 100 for automatically preventing the bicycle from rolling back on the incline, an X represents the termination of the method 100.
[0036] In a first step 110 of method 100, a current inclination angle a and a current output speed nab of the bicycle are determined. Additionally, a current crank torque k of the bicycle can be determined.
[0037] In a subsequent second step 120 of the method, the current inclination angle a is compared with an inclination angle threshold value alim. If the current inclination angle a is less than the inclination angle threshold value alim, the method 100 is aborted, since there is then no sufficiently steep gradient to necessitate the execution of the method 100. If the current inclination angle a is greater than the inclination angle threshold value alim, the method 100 is continued.
[0038] In a subsequent third step 130 of the method, the current output speed nab is compared with an output speed threshold value nablim. If the current output speed nab is less than the output speed threshold value nablim, method 100 is aborted, since there is then no rollback that would necessitate the execution of method 100. If the current output speed nab is greater than the output speed threshold value nablim, method 100 is continued.
[0039] The fourth step 140 shown below is optional and serves to further increase rider safety. In this optional fourth step 140 of method 100, the current crank torque k is compared with the holding torque h, where the holding torque is a value of the bicycle's electric motor. If the current crank torque k is greater than the holding torque h, method 100 is aborted because the bicycle rider applies the necessary muscle power to prevent the bicycle from rolling back. If the current crank torque k falls below the holding torque h, method 100 continues.
[0040] In a final step 150 of method 100, the motor torque m of at least one electric motor is increased until a holding torque h is reached. This effectively prevents the bicycle from rolling back on the incline and increases safety. The final step 150 can follow the third step 130 if the optional fourth step 140 is omitted; otherwise, the final step 150 follows the fourth step 140. Reference symbol
[0041] 1 bicycle
[0042] 2 bicycle gears
[0043] 3 electric drive system
[0044] 4 Pedal
[0045] 5 energy storage
[0046] 6 Crank unit
[0047] 7 gradient
[0048] 20 Control device
[0049] 21 Tilt angle sensor
[0050] 22 Speed sensor
[0051] 23 Crank torque sensor
[0052] 100 procedures
[0053] 110 first step
[0054] 120 second step
[0055] 130 third step
[0056] 140 fourth step
[0057] 150 last step a current inclination angle alim inclination angle threshold nab current output speed nablim output speed threshold k current crank torque h holding torque m engine torque
[0058] X Termination of the procedure
Claims
Patent claims 1. Method (100) for automatically preventing a bicycle (1) from rolling back on an incline (7), wherein the bicycle (1) has a pedal crank unit (6) and an electric drive system (3) with at least one electric motor, wherein - a current angle of inclination (a) and a current output speed (nab) of the bicycle (1 ) are determined, - the current inclination angle (a) is compared with an inclination angle threshold value (alim), - the current output speed (nab) is compared with an output speed threshold value (nablim), - if the inclination angle threshold value (alim) is exceeded by the current inclination angle (a) and if the output speed threshold value (nablim) is exceeded by the current output speed (nab), a motor torque (m) of the at least one electric motor is increased until a holding torque (h) is reached.
2. Method (100) according to claim 1, wherein additionally a current crank torque (k) of the bicycle (1) is determined, wherein the current crank torque (k) is then compared with the holding torque (h), wherein if the current crank torque (k) falls below the holding torque (h), the motor torque (m) of the at least one electric motor is increased until a holding torque (h) is reached, wherein if the current crank torque (k) exceeds or reaches the holding torque (h), the method (100) is ended.
3. Method (100) according to one of the preceding claims, wherein the engine torque (m) is permanently controlled as a function of the current output speed (nab) and as a function of the current inclination angle (a).
4. Control device (20) for a bicycle (1), wherein the control device (20) can be connected to an electric drive system (3) of the bicycle (1) in a signal-effective manner, and wherein the control device (20) comprises means for carrying out the method (100) according to one of claims 1 to 3.
5. A computer program product comprising instructions which, when the program is executed by a control device (20) according to claim 4, cause the control device (20) to carry out the method (100) according to one of claims 1 to 3.
6. A computer-readable medium comprising instructions which, when executed by a control device (20) according to claim 4, cause the control device (20) to carry out the method (100) according to any one of claims 1 to 3.
7. Bicycle (1 ), comprising an electric drive system (3) and a control device (20) according to claim 4, wherein the electric drive system (3) is signal-effectively connected to the control device (20).