Method for determining a cadence of a rider of a bicycle

Abstract

In order to determine a cadence of a rider of a bicycle (1) using at least one sensor for detecting a torque or an angle of rotation or a cadence, at least one cadence signal which correlates with the cadence of the rider is constructed from a temporally pulsing signal profile of a raw sensor signal by means of at least one frequency demodulator. The constructed cadence signal can be used for the open-loop or closed-loop controlling of an electric drive motor of the bicycle or of an actuator of the bicycle or of an electric drive motor of the bicycle and an actuator of the bicycle. Alternatively or additionally, the constructed cadence signal can be used to check the plausibility of a cadence signal of the sensor for cadence detection or of another constructed cadence signal. The method makes it possible, in particular, to dispense with the use of at least one dedicated sensor for detecting the cadence, and thus to reduce costs. The plausibility check can prevent incorrect actuations or incorrect controlling of an electric drive motor of the bicycle or of an actuator of the bicycle, and thus minimise the risk of an accident or injury to the rider of the bicycle.

Description

[0001] ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0002] Method for determining the cadence of a bicycle rider

[0003] The present invention relates to a method for determining the cadence of a cyclist, a control device, a computer program product, a computer-readable medium and a bicycle.

[0004] To control or regulate an electric drive motor or actuator of bicycles such as e-bikes, pedelecs, e-mountain bikes (eMTBs), cargo bikes, tricycles, quad bikes, or snow bikes, a rider's cadence, also known as pedaling frequency, is required. US20180259546 A1 discloses a device for determining the angular velocity and pedaling frequency of a bicycle. The pedaling frequency is determined from a previously filtered signal from an angular velocity sensor of the bicycle using frequency analysis. DE102022212294 A1 discloses a method for determining the pedaling frequency of a bicycle from a motion signal, such as a velocity signal or an acceleration signal, of the bicycle using a fast Fourier transform.

[0005] The object of the present invention is to provide an alternative method for determining the cadence of a bicycle rider. In particular, the method eliminates the need for at least one dedicated sensor for cadence measurement, thus reducing costs. If at least one dedicated sensor is used for cadence measurement, the cadence determined by the method can be used to validate the cadence measured by the sensor. This validation prevents incorrect control or regulation of an electric drive motor or actuator of the bicycle, thereby minimizing the risk of an accident or injury to the cyclist.

[0006] The problem is solved by a method for determining the cadence of a cyclist with the features of claim 1, a control device with the features of claim 11, a computer program product with the features of claim 12, and a computer-readable medium with the features of ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0007] Claim 13 and a bicycle with the features of claim 14. Further embodiments are included in the dependent claims and are described below.

[0008] The invention claims a method, a control device for use on a bicycle such as e-bikes, pedelecs, e-mountain bikes (eMTBs), cargo bikes, tricycles, quad bikes or snow bikes, a computer program product, a computer-readable medium and a bicycle.

[0009] In the method for determining the cadence of a bicycle rider, a cadence signal is constructed from at least one time-varying signal waveform, at least one raw signal from at least one sensor on the bicycle, using at least one frequency demodulator. The sensor can detect torque, angle of rotation, or cadence, for example, from a crank arm, a crank axle, or both. The sensor's raw signal is an unprocessed and, in particular, unfiltered signal that represents a physical quantity over time. The time-varying raw signal waveform can fluctuate between a maximum and minimum value. The minimum value can be zero or, due to the unprocessed and, in particular, unfiltered nature of the raw signal, less than zero.The time-varying signal can arise from a rider's fluctuating pedaling torque over a pedal revolution and the bicycle's kinematics. This time-varying signal can exhibit several periodic harmonics and a periodic fundamental frequency. The frequency of the fundamental frequency is called the base frequency and correlates with the rider's cadence. For example, half the base frequency can correspond to the cadence. It is also possible that a multiple of half the base frequency, such as 1 or 1.5, can correspond to the cadence. Based on the base frequency of the time-varying signal, at least one cadence signal can be constructed using a frequency demodulator, for example, in the form of a control loop such as a phase-locked loop.The constructed cadence signal can be used for controlling or regulating an electric drive motor of a bicycle (ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26) or an actuator of the bicycle, or an electric drive motor of the bicycle and an actuator of the bicycle. For example, when using a constructed cadence signal derived from a time-wavelength signal waveform of a raw signal from the torque sensor, the use of a dedicated sensor for cadence detection or a sensor for angle detection, where the cadence can be determined from a temporal sequence of angles, can be dispensed with. Alternatively or additionally, when using a dedicated sensor for cadence detection, a constructed cadence signal can be used to validate the cadence signal from the sensor.Plausibility checks can prevent incorrect control or regulation of the electric drive motor or actuator, or of the electric drive motor and actuator, and thus minimize the risk of accidents or injuries to the driver.

[0010] The term "bicycle" encompasses all vehicles with at least two wheels, or at least one wheel and at least one sliding element such as a sled runner, located in a plane or on an axle. Examples of bicycles include e-bikes, pedelecs, e-mountain bikes (eMTBs), cargo bikes, tricycles, quadricycles, and snow bikes.

[0011] The bicycle may have a drive system, which may include at least one crank unit. The crank unit may include at least one crank axle and at least one crank arm with at least one pedal. Power from the rider of the bicycle can be fed into the drive system via the crank unit.

[0012] Furthermore, the drive system can have at least one pawl freewheel. The pawl freewheel can comprise at least one inner ring and at least one outer ring. Both rings can be arranged coaxially. The outer ring can have internal teeth in the circumferential direction, and the inner ring can have at least one pawl mounted in the circumferential direction. In a locked state of the pawl freewheel, the pawl is engaged with the internal teeth, allowing torque to be transmitted from the inner ring to the outer ring or vice versa. In a released state of the pawl freewheel, both rings can rotate independently of each other. ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0013] Furthermore, the drive system can include at least one electric drive motor. An electric drive motor, in this context, refers to any drive that can convert electrical power into mechanical power or vice versa, such as DC motors, AC motors, three-phase motors, or similar devices. The driver's power output can be assisted by the electric drive motor.

[0014] Additionally, the drive system can include at least one transmission. The transmission can be, for example, a manual transmission or a continuously variable transmission (CVT). The transmission can be shifted automatically via at least one actuator. Alternatively, the transmission can be a constant-ratio transmission.

[0015] Furthermore, the bicycle may include at least one electrical energy storage device such as batteries, accumulators, capacitors such as supercapacitors or at least one energy converter such as a fuel cell with a chemical storage device consisting of a fuel and oxidant.

[0016] The bicycle can be powered either by pure muscle power, purely electrically, or in hybrid mode by both muscle power and electricity.

[0017] Furthermore, the bicycle can have at least one steering system, for example, in the form of at least one movable axle connected to at least one wheel or at least one sliding element of the bicycle and to the bicycle frame. The movable axle can be connected, for example, to at least one handlebar. Additionally, the movable axle can be connected to at least one actuator in the form of an electric motor. This allows the electric motor to assist the rider's steering movements. Additionally or alternatively, the movable axle can have at least one actuator in the form of a centering spring or a steering damper. The centering spring or steering damper can be adjusted depending on the rider's cadence. To stabilize the bicycle, the restoring force of the centering spring or the damping level of the steering damper can be increased.To increase agility, the restoring force of the centering spring or the damping level of the steering damper can be reduced.

[0018] Furthermore, the bicycle can have at least one brake, which may be a disc brake, a rim brake, or a drum brake (ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26). Additionally, it is possible to combine a brake with at least one anti-lock braking system (ABS). Alternatively or additionally, the bicycle can include at least one brake-by-wire braking system with at least one actuator in the form of an electric servo motor. For example, the actuator can increase the braking force below a certain cadence threshold, close to a standstill, to prevent the bicycle from rolling away unintentionally on an incline.

[0019] The bicycle may have at least one damping system with actuators for adjusting the damping level. The damping level can be adjusted depending on the cadence. The bicycle may also have at least one actuator in the form of a human-machine interface, such as a light signal, a sound signal, a screen, or a wearable device (a computer system that can be worn on the human body). For example, a training assistant on the bicycle could use the actuator to inform the rider that they are outside a predefined cadence range.

[0020] Furthermore, the bicycle can have at least one sensor for torque measurement. This sensor can measure at least the torque of the crank axle, the crank arm, or both the crank axle and the crank arm. Alternatively or additionally, it is also possible to measure torque in the ratchet freewheel. Alternatively or additionally, the bicycle can have at least one sensor for angle measurement. This sensor can measure at least the angle of rotation of the crank axle or a rotating shaft, such as the output shaft of an electric drive motor or a shaft of the bicycle. It is also possible to derive at least one angular velocity from a temporal sequence of angles of rotation. Consequently, at least one angular velocity of the crank axle or a rotating shaft, such as the output shaft of an electric drive motor or a shaft of the bicycle, can be measured.It is also possible to determine the cadence of the crank arm from its angular velocity. Alternatively or additionally, the bicycle can have at least one sensor for cadence detection. This allows for the detection of at least one crank arm cadence. The sensor is related to ZF Friedrichshafen AG, file number 301989, Friedrichshafen, September 26, 2024.

[0021] Torque, angle, or cadence measurement devices can have at least one interface for outputting at least one raw signal. This raw signal can represent at least one physical quantity over time, for example, at least one electrical quantity such as voltage, current, or resistance. The sensor's raw signal is unprocessed and, in particular, unfiltered. In addition to the useful signal containing information about the physical quantity, the raw signal can also contain random signal fluctuations, also known as signal noise. The raw signal can be continuous-time, discrete-time, or partially continuous-time and partially discrete-time. During pedaling, the raw signal can exhibit a fluctuating signal pattern.In a time-varying signal, a signal can fluctuate between a maximum and a minimum value. The minimum value can be zero or, due to the unprocessed and, in particular, unfiltered raw signal, less than zero. This time-varying signal can arise from a rider's periodically fluctuating pedaling torque, which depends on the pedal position and the bicycle's kinematics. For example, the pedaling torque is greater with a horizontal pedal position compared to a vertical one. The varying signal can be decomposed into several periodic overtones and a periodic fundamental oscillation. The fundamental oscillation has a frequency, which is referred to as the fundamental frequency. The fundamental frequency correlates with the rider's cadence. Due to the bicycle's kinematics, half the value of the fundamental frequency can correspond to the rider's cadence.It is also possible that a multiple of half the fundamental frequency, such as a value of 1 or 1.5, can correspond to the cadence. Additionally, the fundamental frequency can exhibit a phase shift. The phase shift describes a time displacement of the fundamental frequency and can be quantified by a zero phase angle.

[0022] Furthermore, the bicycle can have at least one frequency demodulator. Alternatively or additionally, the frequency demodulator can be a component of the bicycle's control unit. The frequency demodulator can be implemented as at least one electronic circuit (ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26) using at least one electronic component on at least one printed circuit board. Alternatively or additionally, the frequency demodulator can also be implemented as at least one integrated circuit in at least one plastic or ceramic housing. Alternatively or additionally, the frequency demodulator can be implemented as at least one binary code, at least one machine code, or at least one program code for at least one microcontroller. Furthermore, it is possible to connect multiple frequency demodulators together.

[0023] The frequency demodulator can preferably be implemented as a control loop, such as a phase-locked loop (PLL) or similar. The phase-locked loop can include at least one phase comparator, at least one loop filter or low-pass filter, and at least one controllable oscillator. Optionally, the phase-locked loop can include a frequency divider. Alternatively, the frequency demodulator can be implemented as at least one discriminator or a coincidence demodulator. Alternatively, the control loop, the phase-locked loop, the discriminator, or the coincidence demodulator can be implemented as at least one binary code, at least one machine code, or at least one program code for at least one microcontroller.

[0024] Using a frequency demodulator in the form of a control loop, at least one cadence signal can be constructed from a time-varying signal waveform of at least one raw signal. The cadence signal can be constructed by matching a previously generated reference oscillation of a reference signal to a fundamental frequency of the time-varying signal waveform of the raw signal. The reference oscillation of the reference signal can have a periodic waveform and can be generated, for example, using a signal generator or a controllable oscillator. When matching the reference oscillation to the fundamental frequency, a frequency of the reference oscillation can be adjusted to a fundamental frequency of the fundamental frequency.Alternatively or additionally, when aligning the reference oscillation to the fundamental oscillation, a zero phase angle of the reference oscillation can be aligned with a zero phase angle of the fundamental oscillation (ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26). The alignment of the reference oscillation to the fundamental oscillation can be performed discretely or continuously, or discretely and continuously. The raw signal can be fed into an input of the frequency demodulator. The cadence signal, which corresponds to the aligned reference signal, can be output at an output of the frequency demodulator.

[0025] It is also possible to quantify the alignment of the reference oscillation to the fundamental oscillation after low-pass filtering of the fundamental frequency using at least one test function. For example, the test function could be implemented as at least one multiplication of two identical or different trigonometric functions, such as a sine or cosine function. A constant result from the test function could then be interpreted as a complete alignment of the reference oscillation to the fundamental oscillation.

[0026] Furthermore, it is possible to change the fundamental frequency of the fundamental oscillation or the frequency of the adjusted reference oscillation of the adjusted reference signal using at least one frequency divider of the frequency demodulator.

[0027] The procedure for determining the cadence of a cyclist can be performed while the cyclist is pedaling or not pedaling.

[0028] In the first step of the process, at least one raw signal is output via at least one interface of the sensor using at least one torque sensor. Alternatively or additionally, at least one raw signal is output via at least one interface of the sensor using at least one angle sensor. Alternatively or additionally, at least one raw signal is output via at least one interface of the sensor using a cadence sensor.

[0029] In a second step, the raw signal is fed into a frequency demodulator via its input. Subsequently, a previously generated reference oscillation of a reference signal is aligned to a fundamental frequency of the raw signal, resulting in a time-dependent, fluctuating signal waveform. During this alignment, a frequency of the reference oscillation is matched to a fundamental frequency of the fundamental oscillation. Alternatively or additionally, a zero phase angle of ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0030] The reference oscillation is aligned to a zero phase angle of the fundamental oscillation. It is possible to halve or change the frequency of the aligned reference oscillation before alignment, or after alignment, using at least one frequency divider in the frequency demodulator, in order to represent the driver's cadence. Consequently, the frequency of the aligned reference oscillation can correspond to the fundamental frequency, half the fundamental frequency, or a multiple of half the fundamental frequency, within a certain tolerance range. The aligned reference signal corresponds to a constructed cadence signal, which is output via an output of the frequency demodulator.In a third step of the procedure, the constructed cadence signal is used for a control or for a regulation of an electric drive motor of the bicycle or an actuator of the bicycle or an electric drive motor of the bicycle and an actuator of the bicycle.

[0031] For example, it is possible to control or regulate the electric drive motor or actuator, or both, using at least one predefined control parameter or regulation parameter based on the constructed cadence signal. For instance, the constructed cadence signal can be compared with a predefined threshold value. Based on the result of this comparison, along with the direction of rotation of a crank axle, pedaling in a forward or reverse direction can be determined. For example, when pedaling forward, the electric drive motor can be controlled with a target torque.

[0032] It is possible, either alternatively or additionally, to use the constructed cadence signal for plausibility checks of a cadence signal from a dedicated sensor for cadence detection. Alternatively or additionally, the constructed cadence signal can be used for plausibility checks of another constructed cadence signal. During plausibility checks, cadence signals from different sources are compared to determine differences between them. Based on these differences, it is determined whether at least one cadence signal lies within physically possible limits. For example, by comparing three cadence signals from different sources (ZF Friedrichshafen AG File 301989, Friedrichshafen, 2024-09-26), it can be determined whether one cadence signal differs from the others by several orders of magnitude.Furthermore, it is also possible, as an alternative or additional measure for plausibility checks, to compare at least one cadence signal with previously defined physical limits. For example, one of the following ranges [0 rpm, +350 rpm] or [-350 rpm, +350 rpm] or similar can be defined as the physical limit.

[0033] Plausibility checks can prevent incorrect control or regulation of the electric drive motor or actuator, or of both, thus minimizing the risk of an accident or injury to the cyclist. The process ends after the third step.

[0034] A control unit for a bicycle can be effectively connected to at least one sensor for torque measurement. Alternatively or additionally, the control unit can be effectively connected to a sensor for angle measurement. Alternatively or additionally, the control unit can be effectively connected to a sensor for cadence measurement.

[0035] The control unit can be effectively connected to at least one electric drive motor of a bicycle, or to at least one actuator of a bicycle, or to at least one electric drive motor of a bicycle and at least one actuator of a bicycle.

[0036] The control unit comprises means for carrying out the method according to the invention. The control unit can, for example, be implemented as an electronic control unit (ECU) or electronic control module (ECM). The electronic control unit can comprise at least one microcontroller, wherein the method can be executed on the microcontroller in the form of at least one binary code, at least one machine code, or at least one program code.

[0037] When the control unit is used in or outside of a bicycle, the control unit is connected to at least one sensor for torque detection, angle detection, or cadence detection.

[0038] A signal-effective connection is such that data and signal exchange between the connection partners is possible. For this purpose, ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26, each connection partner has a corresponding interface. Data transmission and signal transmission can be either wired or wireless. The control unit and the sensor therefore have interfaces that enable such a connection.

[0039] The control unit and the electric drive motor or actuator, or the electric drive motor and actuator, have interfaces that enable a signal-effective connection. Furthermore, the control unit can be configured to control or regulate the electric drive motor or actuator, or both. Additionally, the control unit can be configured to send predefined control parameters to the electric drive motor for controlling the motor, or predefined control parameters to regulate the electric drive motor. The control unit can also be configured to send predefined control parameters to the actuator for controlling the actuator, or predefined control parameters from the actuator to the actuator.

[0040] The control unit can be integrated into a housing with the electric drive motor or with the actuator. The housing can be mechanically connected to a bicycle frame, for example to a bicycle's down tube.

[0041] A computer program product comprises instructions which, when the program is executed by the control device already described, cause it to execute the procedure already described.

[0042] A computer-readable medium comprises instructions that, when executed by the control device described above, cause it to perform the procedure already described. The computer-readable medium can, for example, be in the form of a data carrier or a downloadable data stream.

[0043] Exemplary embodiments of the invention are shown in the figures. Specifically, they show:

[0044] Fig. 1 is a schematic representation of a bicycle according to an exemplary embodiment. ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0045] Fig. 2 An exemplary schematic representation of a time-dependent, fluctuating signal waveform of a raw signal from a sensor for torque detection and a signal waveform of a constructed cadence signal.

[0046] Fig. 3 shows an exemplary schematic representation of a time-wavelength signal waveform of a raw signal from a sensor for cadence detection and a signal waveform of a constructed cadence signal.

[0047] Fig. 4 shows a diagram of the process for determining the cadence of a cyclist from Fig. 1.

[0048] Fig. 5 shows an alternative sequence of the procedure for determining the cadence of a cyclist from Fig. 1.

[0049] 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 e-mountain bike. The bicycle 1 has a drive system 2. The drive system 2 comprises an electric drive motor E, a crank unit 3, a sensor SenM for torque detection, a sensor SenD for angle detection, and a sensor SenK for cadence detection. The crank unit 3 comprises at least one crank axle 4, at least one crank arm 5, and at least one pedal 6. The sensor SenM for torque detection detects a torque at the crank axle 4 and generates a raw signal RawSigM, which is output via an interface of the sensor SenM. The sensor SenD for angle detection detects an angle of rotation at the crank axle 4 and generates a raw signal RawSigD, which is output via an interface of the sensor SenD.It is possible to derive an angular velocity at the crank arm 4 from a temporal sequence of rotation angles of the crank arm 4. From the determined angular velocity, a cadence at the crank arm 4 can be calculated. The SenK sensor for cadence detection records the cadence of the crank arm 5 and generates a raw signal RawSigK, which is output via an interface of the SenK sensor.

[0050] Additionally, the drive system 2 features a gearbox with an actuator A for automated gear shifting. The electric drive motor E, the crank unit 3, and the gearbox with the actuator A can be located in the bottom bracket area. ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0051] Furthermore, the drive system 2 has an electrical energy storage device 7, which is connected to the electric drive motor E. Additionally, the electrical energy storage device 7 can supply the electric drive motor E with electrical energy (motor operation) or can be supplied with electrical energy by the electric drive motor E (generator operation). The bicycle 1 can therefore be driven either purely by muscle power, purely electrically, or by both muscle power and electrically.

[0052] The drive system 2, the electric drive motor E, the actuator A, the electric energy storage device 7, the sensor SenM for torque detection, the sensor SenD for rotation angle detection and the sensor SenK for cadence detection are connected to a control unit EC of the bicycle 1 in a signal-effective manner.

[0053] Furthermore, bicycle 1 has a steering system consisting of a movable axle 8 and a handlebar 9. The movable axle 8 is connected to the bicycle frame of bicycle 1, as well as to the handlebar 9 and a front wheel 11 of bicycle 1. The movable axle 8 can be rotated about its rotationally symmetrical axis by means of the handlebar 9, thereby steering the front wheel 11. Bicycle 1 also has a brake 10, which can be, for example, a disc brake, a rim brake, or a drum brake. It is also possible to combine the brake with an anti-lock braking system (ABS). Actuating the brake 10 reduces or prevents the rotation of a rear wheel 12. The brake 10 is connected to the control unit EC via a signal.

[0054] Fig. 2 shows an exemplary schematic representation of a time-dependent, fluctuating signal waveform of a raw signal SigRawM from a torque sensor and a signal waveform of a constructed cadence signal ConSigM. The time-dependent, fluctuating signal waveform of the raw signal SigRawM from the torque sensor SenM is shown over time t. The signal waveform oscillates between a minimum and a maximum value, with the minimum value being greater than or equal to zero. Furthermore, the signal waveform exhibits random fluctuations. Additionally, the signal waveform has a fundamental oscillation. The fundamental oscillation (ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26) comprises a fundamental frequency that correlates with a driver's cadence.From the time-varying signal waveform of the raw signal SigRawM, a cadence signal ConSigM can be constructed using the method according to the invention. The signal waveform of the constructed cadence signal ConSigM is also plotted over time t. The signal waveform of the constructed cadence signal ConSigM exhibits a reference oscillation that is aligned with the fundamental oscillation. A frequency of the aligned reference oscillation corresponds to the fundamental frequency of the fundamental oscillation, taking into account a tolerance range. Furthermore, a zero phase angle of the aligned reference oscillation corresponds to the zero phase angle of the fundamental oscillation, also taking into account a tolerance range. The aligned reference oscillation and the fundamental oscillation oscillate in phase.

[0055] Fig. 3 shows an exemplary schematic representation of a time-dependent, fluctuating signal waveform of a raw signal SigRawK from a sensor for cadence detection and of a signal waveform of a constructed cadence signal ConSigK. The description of Fig. 4 can be applied analogously to the time-dependent, fluctuating signal waveform of the raw signal SigRawK and the signal waveform of the constructed cadence signal ConSigK.

[0056] Fig. 4 shows a diagram of the process for determining the cadence of a cyclist from Fig. 1. In a first step 101 of the process 100, a raw signal RawSigM is output via an interface of a torque sensor. In a second step 102 of the process 100, a cadence signal ConSigM is constructed from at least one time-wavelength signal waveform of the raw signal RawSigM using a frequency demodulator FreqDem in the form of a phase-locked loop. For this purpose, the raw signal RawSigM is fed into the frequency demodulator FreqDem via its input. Subsequently, a previously generated reference oscillation of a reference signal is aligned to a fundamental oscillation of the time-wavelength signal waveform of the raw signal RawSigM using the frequency demodulator FreqDem.For this purpose, the frequency of the reference oscillation is aligned to a fundamental frequency of the fundamental oscillation, and the zero phase angle of the reference oscillation is aligned to a zero phase angle of the fundamental oscillation. The reference signal (ZF Friedrichshafen AG File 301989, Friedrichshafen, 2024-09-26) can be generated internally in the frequency demodulator FreqDem or externally using a signal generator. The aligned reference signal, which corresponds to the constructed cadence signal ConSigM, is output via an output of the frequency demodulator FreqDem. In a third step 103 of the method 100, the constructed cadence signal ConSigM is used for controlling or regulating an electric drive motor E of the bicycle 1 from Fig. 1 and an actuator A of the bicycle 1's gearbox from Fig. 1. The method 100 is then terminated.

[0057] Fig. 5 shows an alternative sequence of the method for determining the cadence of a cyclist from Fig. 1. In a first step 111 of the method 100, a raw signal RawSigM is output via an interface of the torque sensor using a torque sensor. Additionally, a raw signal RawSigD is output via an interface of the angle sensor using a rotation sensor. Furthermore, a raw signal RawSigK is output via an interface of the angle sensor using a cadence sensor. This is analogous to step 102 from Fig.In a second step 112, a frequency demodulator FreqDem is used to construct a cadence signal ConSigM from the time-wavelength signal waveform of the raw signal RawSigM, a cadence signal ConSigD from the time-wavelength signal waveform of the raw signal RawSigD, and a cadence signal ConSigK from the time-wavelength signal waveform of the raw signal RawSigK. In this case, the frequency demodulator FreqDem has three inputs and three outputs. In a third step 113, the previously constructed cadence signals ConSigM, ConSigD, ConSigK, and a cadence signal SenSigK from the sensor for cadence detection are validated. During plausibility checks (Plausi), the constructed cadence signals ConSigM, ConSigD, ConSigK and the cadence signal SenSigK are compared to determine differences between the cadence signals ConSigM, ConSigD, ConSigK, SenSigK.Based on the determined differences, it is established whether at least one cadence signal ConSigM, ConSigD, ConSigK, SenSigK lies within physically possible limits. The cadence signals ConSigM, ConSigD, ConSigK, SenSigK that lie outside physically possible limits are listed in ZF Friedrichshafen AG File 301989, Friedrichshafen, 2024-09-26.

[0058] Boundaries can, for example, be displayed to the rider of bicycle 1 from Fig. 1. The procedure is then terminated.

[0059] ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0060] Reference mark

[0061] 1 bicycle

[0062] 2 Drive system

[0063] 3 Crank unit

[0064] 4. Crankshaft

[0065] 5 Crankset

[0066] 6 pedal

[0067] 7 electrical energy storage

[0068] 8 movable axes

[0069] 9 Steering wheel

[0070] 10 Brake

[0071] 11 front wheel

[0072] 12 rear wheel

[0073] 100 procedures

[0074] 101 First Step

[0075] 102 second step

[0076] 103 third step

[0077] 111 alternative first step

[0078] 112 alternative second step

[0079] 113 alternative third step

[0080] E electric drive motor

[0081] A actor

[0082] EC control unit

[0083] SenM sensor for torque measurement

[0084] SenD sensor for rotation angle detection

[0085] SenK sensor for cadence detection

[0086] Start of procedure

[0087] Stop procedure end t time

[0088] Plausibility check

[0089] FreqDem Frequency Demodulator IF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26

[0090] RawSigM raw signal from a sensor for torque measurement

[0091] RawSigD raw signal from a sensor for rotation angle detection

[0092] RawSigK raw signal from a sensor for cadence detection

[0093] ConSigM constructed a cadence signal from a time-wavelength signal waveform of a raw signal from a sensor for torque measurement.

[0094] ConSigD constructed a cadence signal from a time-wavelength signal waveform of a raw signal from a sensor for rotation angle detection.

[0095] ConSigK constructed a cadence signal from a time-wavelength signal waveform of a raw signal from a sensor for cadence detection.

Claims

ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26 Patent claims 1. Method for determining the cadence of a rider of a bicycle (1) with at least one sensor (SenM, SenD, SenK) for torque detection or rotation angle detection or cadence detection, wherein during pedaling by the rider at least one raw signal of the sensor (SenM, SenD, SenK) has at least one time-wavelength signal profile, characterized in that at least one cadence signal (ConSigM, ConSigD, ConSigK) correlated to the cadence of the rider is constructed from the time-wavelength signal profile of the raw signal (RawSigM, RawSigD, RawSigK) of the sensor (SenM, SenD, SenK) by means of at least one frequency demodulator (FreqDem).

2. Method according to claim 1, characterized in that the frequency demodulator (FreqDem) can be implemented as at least one control loop, wherein the control loop can preferably be implemented as at least one phase-controlled loop.

3. Method according to claim 1, characterized in that the time-varying signal waveform of the raw signal (RawSigM, RawSigD, RawSigK) has at least one fundamental oscillation, wherein the fundamental oscillation has a fundamental frequency and a zero phase angle, wherein the fundamental frequency correlates with the cadence of the driver.

4. Method according to claims 1 to 3, characterized in that a previously generated reference oscillation of a reference signal is aligned to the fundamental oscillation by means of the frequency demodulator (FreqDem) in order to construct the cadence signal.

5. Method according to claim 4, characterized in that the reference oscillation of the reference signal has a periodic signal waveform, wherein the reference oscillation of the reference signal can be generated by means of a signal generator or a controllable oscillator. ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26 6. Method according to claim 4, characterized in that a frequency of the reference oscillation is adjusted to the fundamental frequency of the fundamental oscillation or a zero phase angle of the reference oscillation is adjusted to the zero phase angle of the fundamental oscillation or a frequency of the reference oscillation is adjusted to the fundamental frequency of the fundamental oscillation and a zero phase angle of the reference oscillation is adjusted to the zero phase angle of the fundamental oscillation.

7. Method according to claims 1 to 6, characterized in that the constructed cadence signal (ConSigM, ConSigD, ConSigK) can be used for plausibility checks (plausi) of at least one cadence signal (SenSigK) of the sensor (SenK) for cadence detection.

8. Method according to claims 1 to 6, characterized in that the constructed cadence signal (ConSigM, ConSigD, ConSigK) can be used for plausibility checks (plausi) of at least one further constructed cadence signal (ConSigM, ConSigD, ConSigK).

9. Method according to claims 1 to 6, characterized in that the constructed cadence signal (ConSigM, ConSigD, ConSigK) is compared for plausibility (plausi) with at least one previously defined physical limit.

10. Method according to claims 1 to 6, characterized in that the constructed cadence signal (ConSigM, ConSigD, ConSigK) can be used to control or regulate at least one electric drive motor (E) of the bicycle (1 ) or at least one actuator (A) of the bicycle (1) or at least one electric drive motor (E) of the bicycle (1 ) and at least one actuator (A) of the bicycle (1 ).

11. Control device (EC) for a bicycle (1) , characterized in that at least one sensor (SenM, SenD, SenK) for torque detection or rotation angle detection or cadence detection is connected to the control device (EC) ZF Friedrichshafen AG File 301989 Friedrichshafen 2024-09-26 is signal-effectively connectable, and wherein the control device (EC) comprises means for carrying out the method (100) according to one of claims 1 to 10.

12. Computer program product comprising instructions which, when the program is executed by a control device (EC), cause the method (100) according to any one of claims 1 to 10 to be executed.

13. Computer-readable medium comprising instructions which, when executed by a control device (EC), cause it to execute the method (100) according to any one of claims 1 to 10.

14. Bicycle (1 ) with a control device (EC) according to claim 11.

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