Device for acoustic rider feedback for a bicycle with electric auxiliary motor

Abstract

The present invention relates to a device for acoustic rider feedback for a bicycle with an electric auxiliary motor. The device is configured to receive a status signal from the bicycle. The device is further configured to generate a control signal based on the status signal, which is configured to generate acoustic rider feedback in the electric auxiliary motor.

Description

State of the art

[0001] The present invention relates to a device for acoustic rider feedback for a bicycle with an electric auxiliary motor, as well as a method for generating acoustic rider feedback, a computer program and a computer-readable medium for carrying out the method.

[0002] Electric bicycle drives are available in various designs from the state of the art. Electric bicycle drives are generally designed to be quiet. Nevertheless, many customers still desire an audibly powerful drive. This initially leads to a contradiction.

[0003] It would be desirable to have a bicycle with an electric auxiliary motor that can control the noise of the auxiliary motor depending on the condition and mask unwanted sound components of the bicycle. Disclosure of the invention

[0004] The device unit according to the invention for acoustic rider feedback for a bicycle with an electric auxiliary motor, having the features of claim 1, has the advantage that the cyclist can be given state-dependent acoustic feedback about the riding situation. Furthermore, the device according to the invention enables the masking of unwanted noise components. Thus, the riding experience of the user of the device according to the invention can be improved. This is achieved according to the invention in that the device is configured to receive a status signal from the bicycle. Furthermore, the device is configured to generate a control signal based on the status signal. The control signal is configured to generate acoustic rider feedback in the electric auxiliary motor of the bicycle. The control signal is preferably added to a motor current, which is configured to generate a target torque and excite the auxiliary motor.The additional signal of the control signal generates a defined vibration in the auxiliary motor and results in a defined acoustic driver feedback.

[0005] The subclaims show preferred developments of the invention.

[0006] Further preferably, the control signal is configured to excite a radial force and / or a torque fluctuation in the electric auxiliary motor. Permanent-magnet synchronous electric machines are often controlled via field-oriented control. In field-oriented control, a coordinate system rotating with the rotor is defined with the orthogonal axes d and q. The d direction points in the radial direction, the q direction in the tangential direction. If a current is set in the d direction, the motor does not generate torque, but only radial forces. If a current is set in the q direction, the motor generates torque. By a defined excitation of the auxiliary motor, so that a radial force or a torque fluctuation is induced, the auxiliary motor can be excited to emit an acoustic signal to the driver. The control signal calculated by the device can be fed in three different forms as an excitation signal.The control signal can be added to the torque demand of a drive controller. Alternatively, the control signal can be added as the d-current required for the standard current calculation, or it can be added to the q-current calculated from the torque required.

[0007] Particularly preferably, the status signal comprises a motor torque, a motor angle, and / or a bicycle acceleration, and / or a bicycle torque, and / or a motor speed, and / or motor phase currents. The rider torque, the motor angle, the bicycle acceleration, and / or the motor phase currents are measured directly using sensors. The motor speed can be estimated using the motor angle. Furthermore, the motor torque can be estimated using the motor angle and the motor currents. The status signals enable reliable detection of the driving situation and corresponding generation of a control signal, which generates acoustic feedback in the electric auxiliary motor.

[0008] The amplitude of the control signal preferably depends on the motor torque and / or the rider torque and / or the bicycle acceleration. A higher amplitude of the control signal results in louder acoustic feedback from the electric auxiliary motor to the rider. The status signals depend on the current drive power of the bicycle and thus enable enhanced acoustic feedback in riding situations with high drive power.

[0009] More preferably, the frequency of the control signal depends on the bicycle acceleration and / or the motor speed. By integrating the bicycle acceleration over time, the bicycle speed can be determined. Thus, using the bicycle acceleration and / or the motor speed, a speed-dependent acoustic signal can be transmitted from the electric auxiliary motor to the rider, which can improve the perceived sound.

[0010] The control signal is preferably generated based on a sine wave, a triangular wave, a rectangular wave, and / or a noise signal with a downstream bandpass filter. Thus, a simple base signal can be used to generate the control signal, which subsequently generates acoustic driver feedback.

[0011] Further preferably, the device is configured to generate haptic rider feedback in the electric auxiliary motor. Haptic rider feedback is generated by a control signal with a lower frequency and / or higher amplitude than a control signal for acoustic rider feedback. The haptic rider feedback can be provided in addition to or as an alternative to the acoustic rider feedback and can enhance the user experience of a bicycle with an electric auxiliary motor. The haptic rider feedback is preferably generated by the electric auxiliary motor and transmitted to the rider via the pedals, the saddle, and / or the handlebar grips.

[0012] Furthermore, the invention describes a method for generating acoustic rider feedback for a bicycle with an electric auxiliary motor. The method comprises a first step in which a status signal from the bicycle is received. In a subsequent step, a control signal for the electric auxiliary motor is calculated based on the status signal, which is then controlled with the calculated control signal.

[0013] Furthermore, the invention describes a computer program comprising instructions which cause the device described above to carry out the method steps of the method described above.

[0014] Furthermore, the invention describes a computer-readable medium on which the above-described computer program is stored. Short description of the drawings

[0015] Embodiments of the invention are described in detail below with reference to the accompanying drawings. In the drawing: Fig. 1 is a schematic representation of a bicycle with an electric auxiliary motor and a device for acoustic driver feedback according to a first embodiment, Fig. 2 a schematic representation of an engine control system with a device for acoustic driver feedback according to the first embodiment, Fig. 3 is a schematic representation of the device for acoustic driver feedback according to the first embodiment, Fig. 4 is a schematic diagram of a waveform generator of a device for acoustic driver feedback according to the first embodiment, Fig. 5 a schematic noise radiation due to an engine radial force excitation, and Fig. 6 a schematic noise radiation caused by excitation via engine torque fluctuations. Preferred embodiments of the invention.

[0016] The following is based on the Fig. 1 to 4, a device 1 for acoustic driver feedback for a bicycle 100 with an electric auxiliary motor is described.

[0017] Fig. 1 shows a bicycle 100 with a battery pack 102 and an electric auxiliary motor 101. Furthermore, the bicycle 100 has a device 1 which is configured to generate an acoustic rider feedback 2 in the electric auxiliary motor 101.

[0018] Fig. 2 shows a motor control 22. Sensors 5 detect status signals 3 of the bicycle 100. The status signals 3 are further transmitted to a drive controller 8, which calculates a target torque 9 for the electric auxiliary motor 101.

[0019] Furthermore, status signals 3 are transmitted from the sensors 5 to the device 1. Status signals 3 are, for example, a motor torque 7, a motor angle, a bicycle acceleration, a rider torque, a motor speed 11, and / or a motor phase current.

[0020] Some of the state signals 3 can be extended by a state estimator 6. For example, the state estimator 6 makes it possible to determine a motor speed from the motor angle, or to determine a motor torque 7 from the motor angle and the motor current.

[0021] Using the status signals 3, the device 1 calculates a control signal 4. The control signal 4 is added to the target torque 9 and provided to a motor controller 21. The motor controller 21 generates an excitation signal 23, which excites the electric auxiliary motor 101. In doing so, the motor controller 21 takes into account status signals 3 from the electric auxiliary motor 101, such as motor phase currents or motor angles.

[0022] Since the excitation signal 23 includes the control signal 4 of the device 1, the electric auxiliary motor 101 generates a force fluctuation 10, which generates an acoustic driver feedback 2.

[0023] Fig. Figure 3 shows a schematic representation of the device 1 according to the first embodiment. The device 1 receives the engine speed 11 and the engine torque 7 as status signals 3.

[0024] The engine speed 11 is first divided into different orders of engine speed 11 by an order analysis 24. The engine speed is divided into a modulation frequency 30 and further instantaneous frequencies 31. Each order is assigned a signal waveform generator 25, which generates a signal waveform 28. The signal waveforms 28 of the instantaneous waveforms 31 are combined and merged with the signal waveform 28 of the modulation frequency 30 by an amplitude modulation 26.

[0025] The resulting signal waveform 28 is adjusted in amplitude by a volume adjustment 27. The volume adjustment 27 takes into account the status signal 3 of the engine torque 7. After the volume adjustment 27, the device 1 outputs the control signal 4, which is configured to generate an acoustic driver feedback 2 in the electric auxiliary motor 101.

[0026] Fig. 4 shows a schematic representation of the waveform generator 25 of the device 1. The waveform generator 25 receives a state signal 3 which is based on the motor speed 11. The waveform generator contains a selection of functions, such as a sine wave 12, a triangular wave 13, a rectangular wave 14 and noise 15 with a downstream bandpass filter 16. The functions are parameterized via the state signal 3. For example, by calculating a signal angle for a sine wave 12 by forming an integral of a product of the atomic number and the motor angular speed in sum with an offset frequency at speed 0 over time. This results in a frequency response that is linear over the speed and has an offset at speed 0. The resulting signal wave 28 can then be amplitude modulated to obtain a control signal 4.

[0027] Fig. 5 shows an electric auxiliary motor 101 of a bicycle 100. The electric auxiliary motor 101 is excited by a control signal 4, which generates a radial force 24 between the rotor and the stator of the electric auxiliary motor 101. The radial force 24 results in acoustic rider feedback 2 and may also include haptic rider feedback.

[0028] Fig. 5 shows an electric auxiliary motor 101 of a bicycle 100. The electric auxiliary motor 101 is excited by a control signal 4, which generates a torque fluctuation 25 between the rotor and the stator of the electric auxiliary motor 101. The torque fluctuation 25 results in acoustic rider feedback 2 and may also include haptic rider feedback.

Claims

[1] Device (1) for acoustic driver feedback (2) for a bicycle (100) with electric auxiliary motor (101), - wherein the device (1) is arranged to receive a status signal (3) of the bicycle, and - wherein the device (1) is configured to generate a control signal (4) based on the status signal (3), which control signal is configured to generate an acoustic driver feedback (2) in the electric auxiliary motor (101). [2] Device according to claim 1, wherein the control signal (4) is arranged to excite a radial force (24) and / or a torque fluctuation (25) in the electric auxiliary motor (101). [3] Device according to one of the preceding claims, wherein the status signal (3) comprises a motor torque (7) and / or a motor angle and / or a bicycle acceleration and / or a rider torque and / or a motor speed (11) and / or motor phase currents. [4] Device according to claim 3, wherein an amplitude of the control signal (4) depends on the engine torque (7) and / or on the driver torque and / or on the bicycle acceleration. [5] Device according to claim 3 or 4, wherein a frequency of the control signal (4) depends on the bicycle acceleration and / or on the engine speed (11). [6] Device according to one of the preceding claims, wherein the control signal (4) is generated on the basis of a sine wave (12) and / or a triangular wave (13) and / or a rectangular wave (14) and / or a noise (15) with a downstream bandpass filter (16). [7] Device according to one of the preceding claims, wherein the device (1) is arranged to generate a haptic driver feedback in the electric auxiliary motor (101). [8] Method for generating acoustic driver feedback (2) for a bicycle (100) with an electric auxiliary motor (101), comprising the steps: - Receiving a status signal (3) of the bicycle, - calculating a control signal (4) for the electric auxiliary motor (101) based on the status signal (3), - Controlling the electric auxiliary motor (101) with the calculated control signal (4). [9] A computer program comprising instructions causing the device (1) of any one of claims 1 to 7 to carry out the method steps of claim 8. [10] A computer-readable medium on which the computer program according to claim 9 is stored.

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