Method and control device for determining a rotational speed using an incremental measuring system for a micromobility vehicle

Abstract

In the method for determining the rotational speed of a micromobility vehicle using an incremental measuring system, at least one duty cycle is determined from at least one sensor signal of a sensor element of the incremental measuring system while the rotational speed of an incremental element of the incremental measuring system remains constant. Depending on at least one comparison between the determined duty cycle and at least one previously defined limit, it is determined whether, for at least one subsequent determination of the rotational speed of the incremental element, the rotational speed is determined per signal segment of the incremental element or per signal segment pair of the incremental element. This method enables the determination of a rotational speed with sufficient accuracy, even when the air gap width is outside a tolerance range, while halving the measurement resolution. By determining a rotational speed with sufficient accuracy for controlling an electric drive motor or an anti-lock braking system (ABS) of a micromobility vehicle, this method can prevent incorrect control. Consequently, the risk of accidents and injuries to the driver of the micromobility vehicle is minimized.

Description

[0001] The present invention relates to a method for determining a rotational speed by means of an incremental measuring system for a micromobility vehicle, a control device, a computer program product, a computer-readable medium and a micromobility vehicle.

[0002] To determine a vehicle's longitudinal speed or to control a vehicle's anti-lock braking system, the rotational speed of a wheel is required. An incremental measuring system comprising at least one sensor element and at least one incremental element is frequently used to determine the rotational speed of a wheel. The sensor element and the incremental element are magnetically coupled via an air gap. The incremental element comprises at least one pair of signal paths consisting of two signal paths. These two signal paths have a distinguishable magnetic effect on the sensor element. When the incremental element rotates, the signal paths are detected by the sensor element and generate a sensor signal, from which the rotational speed of the incremental element can be determined.Determining the rotational speed using the sensor element and the incremental element is influenced by the air gap width, which is why a predefined tolerance range for the air gap width must be maintained. Therefore, checking the air gap width is necessary.

[0003] EP 0 955 522 A1 discloses a method and a circuit for checking the air gap width of the air gap between a sensor element and an incremental element using a duty cycle determined from the sensor element. A duty cycle within a predefined limit indicates at least one air gap width within a predefined tolerance range. Conversely, a duty cycle outside the predefined limit range indicates at least one air gap width outside the predefined tolerance range. This method can therefore only detect deviations of the air gap width from a predefined tolerance range.

[0004] US Patent 2021 / 0 075 347 A1 discloses a method for determining rotational speed while maintaining high time resolution, as well as a power conversion device that uses this method. In the power conversion device, a speed calculation unit measures the duty cycle of output pulses from an encoder connected to a motor and calculates a rotational speed based on half-periods of the output pulses if the duty cycle is within a predetermined range of approximately 50%; if the duty cycle is outside this range, the rotational speed is calculated based on full periods of the output pulses.

[0005] DE 42 16 142 A1 discloses a method and a device for monitoring a sensor, in particular a sensor which is located at a certain distance from a periodically moving part, wherein the distance is measured and evaluated electronically.

[0006] US Patent 5,608,277 A discloses a rotary pulse generator mounted on a machine shaft, comprising a rotor with a periodic pulse generation pattern and a stator housing with a sensor assembly that detects the rotational speed of the rotor. The sensor is radially spaced from the rotor by a sensor gap. The sensor can be moved between a contact position (at the rotor) and a retracted position to adjust the sensor gap.

[0007] DE 10 2010 045 952 A1 discloses a sensor system for measuring the rotational speed of a rotatable machine element, in particular a wheel hub, comprising a signal transmitter, a first and a second sensor, wherein the signal transmitter is coupled to the rotatable machine element and is arranged concentrically to its axis of rotation and has alternating information areas of two different types in the circumferential direction. Furthermore, a method for measuring rotational speed using two sensors is disclosed.

[0008] The object of the present invention is to provide a method for determining a rotational speed with sufficient measurement accuracy using an incremental measuring system, even when the air gap width of the incremental measuring system lies outside a previously defined tolerance range, and to provide an application of this method in a micromobility vehicle.

[0009] The problem is solved by a method for determining a rotational speed using an incremental measuring system with the features of claim 1, a control device with the features of claim 10, a computer program product with the features of claim 11, a computer-readable medium with the features of claim 12, and a micromobility vehicle with the features of claim 13. Further embodiments are included in the dependent claims and are described below.

[0010] The invention claims a method, a control device for use on a micromobility vehicle, a computer program product, a computer-readable medium and a micromobility vehicle.

[0011] In the method for determining the rotational speed of a micromobility vehicle using an incremental measuring system, a sensor element of the incremental measuring system is fixedly mounted on the vehicle frame of the micromobility vehicle, and an incremental element of the incremental measuring system is non-rotatably connected to a rotatable wheel of the micromobility vehicle. At the beginning of the method, at least one determination of at least one rotational speed or at least one specification for determining at least one rotational speed per signal segment or per signal segment pair is defined, depending on a selection condition. If the selection condition is met, at least one rotational movement with a constant rotational speed of the incremental element is generated by means of at least one control of the electric drive motor or at least one rotational movement with a constant rotational speed of the wheel.The constant rotational speed can be set during at least one movement of the micromobility vehicle with at least one wheel in surface contact, or during at least one standstill of the micromobility vehicle with at least one wheel without surface contact. Subsequently, at least one duty cycle is determined from at least one sensor signal of the sensor element. The determined duty cycle is compared with a previously defined limit. Depending on the comparison, a setting for determining the rotational speed is stored in at least one data memory location. This setting specifies whether, in at least one subsequent determination of at least one rotational speed, the rotational speed is determined per signal segment or per signal segment pair.If at least one duty cycle lies within the previously defined limit range, a rotational speed is determined for each signal path; conversely, if at least one duty cycle lies outside the previously defined limit range, a rotational speed is determined for each pair of signal paths. Furthermore, depending on the comparison between the duty cycle and the previously defined limit range, at least one notification perceptible to human senses is generated.

[0012] The method enables the determination of a rotational speed with sufficient accuracy, even when the air gap width is outside a tolerance range, despite halving the measurement resolution due to the specification of determining a rotational speed per signal path pair instead of per signal path. Furthermore, a notification is generated when the duty cycle is outside the previously defined limit range, and thus when the air gap width is outside the previously defined tolerance range, to inform the driver of the micromobility vehicle to have the air gap width adjusted during maintenance.For example, determining the rotational speed with sufficient accuracy can prevent malfunctions in the control of an electric drive motor or anti-lock braking system of a micromobility vehicle. Consequently, the risk of accidents and injuries to the driver of the micromobility vehicle is minimized.

[0013] The term micromobility vehicle refers to a motorized or non-motorized vehicle that is characterized by its compact and lightweight design and is primarily intended for individual passenger transport.

[0014] Micromobility vehicles are vehicles in which at least two wheels, or at least one wheel and at least one sliding element such as a sled runner, are located in a plane or on an axle. Consequently, micromobility vehicles can be single-track, two-track, or multi-track vehicles. In particular, micromobility vehicles include vehicles with at least one electric drive motor, such as e-bikes, pedelecs, S-pedelecs, e-mountain bikes (eMTBs), cargo bikes, tricycles, quadricycles, velomobiles, snow bikes, e-snow bikes, e-scooters, e-rollers, Segways, etc.

[0015] A micromobility vehicle may have a drive system, which may include at least one pedal crank unit. The pedal crank unit may include at least one pedal crank shaft and at least one pedal crank with at least one pedal. The pedal crank unit allows the driver of the micromobility vehicle to input power into the drive system to generate a rotary motion in a rotating wheel of the micromobility vehicle. The driver's power output is proportional to the rotary motion of the pedal crank generated by the driver.

[0016] Furthermore, the drive system can include at least one electric drive motor. An electric drive motor, in this context, refers to any drive system capable of converting electrical power into mechanical power or vice versa, such as DC motors, AC motors, three-phase motors, or similar devices. In addition to muscular pedaling force, the electric drive motor can variably generate a supporting pedal force, thereby partially or completely replacing the driver's power output with the mechanical power of the electric drive motor. This supporting pedal force can act simultaneously with the driver's muscular pedaling force. A driver can perceive changes in the supporting pedal force through haptic feedback, as the muscular pedaling force can be influenced by the supporting pedal force.For example, if the assisted pedal force is increased, a driver can reduce the muscular pedal force they generate to maintain a constant speed of the micromobility vehicle. This can also be reversed. To propel the micromobility vehicle at a constant speed with a reduced assisted pedal force, a driver can increase the muscular pedal force they generate.

[0017] Consequently, the micromobility vehicle can be powered either by pure muscle power or purely electrically, or by both muscle power and electrically.

[0018] Additionally, the drive system can include at least one automatic transmission with at least one discrete gear ratio. A gear can be defined for each discrete gear ratio of the automatic transmission. Depending on the gear ratio or gear, the automatic transmission can convert rotation with high speed and low torque into rotation with low speed and high torque, and vice versa. During a shift, the automatic transmission changes the gear ratio or gear without driver intervention, using at least one actuator of the automatic transmission, for example, based on the driver's cadence or torque, or at least the rotational speed of one of the micromobility vehicle's wheels.

[0019] Furthermore, the micromobility vehicle may include at least one energy storage device such as batteries, accumulators such as lithium-ion batteries, capacitors such as supercapacitors or at least one energy converter such as a fuel cell such as a polymer electrolyte fuel cell with a chemical storage device consisting of a fuel such as hydrogen or methanol and an oxidizing agent such as air or oxygen.

[0020] Furthermore, the micromobility vehicle 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 sliding element of the micromobility vehicle and to a vehicle frame. The movable axle can be connected, for example, to at least one steering linkage. Additionally, the movable axle can be connected to at least one electric motor. This allows the electric motor to assist the driver's steering input. Additionally or alternatively, the movable axle can have at least one centering spring or steering damper. The centering spring or steering damper can be adjusted depending on at least one rotational speed of a wheel of the micromobility vehicle.To stabilize the micromobility vehicle, 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.

[0021] Furthermore, the micromobility vehicle can have at least one brake, which can be a disc brake, a rim brake, or a drum brake. Additionally, it is possible to combine a brake with at least one anti-lock braking system (ABS). The ABS functions depending on the rotational speed of one of the micromobility vehicle's wheels. Alternatively or additionally, the micromobility vehicle can include at least one brake-by-wire braking system with at least one electric actuator. For example, the electric actuator can increase the braking force below a certain threshold of at least one wheel's rotational speed, close to bringing the micromobility vehicle to a standstill, thus preventing it from rolling away unintentionally on an incline or decline.

[0022] The micromobility vehicle may have at least one damping system with at least one actuator for adjusting the damping level. The damping level can be adjusted depending on at least one rotational speed of a wheel of the micromobility vehicle.

[0023] Furthermore, the micromobility vehicle can have at least one acceleration sensor. The longitudinal acceleration and longitudinal velocity of the micromobility vehicle can be determined using the acceleration sensor. The acceleration sensor is preferably designed as a micro-electro-mechanical system acceleration sensor or as a piezoelectric acceleration sensor.

[0024] The micromobility vehicle may also have at least one 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). The human-machine interface can be located on the handlebars of the micromobility vehicle. The human-machine interface must be capable of generating at least one notification perceptible to human senses. This notification can be visual, audible, or haptic. For example, at least one notification can be generated visually using at least one screen or at least one light signal of the human-machine interface. Alternatively or additionally, at least one notification can be generated audibly using at least one speaker of the human-machine interface.Alternatively or additionally, at least one notification can be generated haptically using at least one vibration motor. A driver of the micromobility vehicle will be informed via the human-machine interface if at least one air gap width falls outside a previously defined tolerance range. The same applies if at least one duty cycle falls outside a previously defined limit range.

[0025] The micromobility vehicle has at least one incremental measuring system. The incremental measuring system comprises at least one sensor element and at least one incremental element. The sensor element is fixed to a vehicle frame of the micromobility vehicle, and the incremental element of the measuring system is non-rotatably connected to a rotating wheel of the micromobility vehicle. A fixed connection or a non-rotatable connection is a mechanical connection that prevents relative movement of connected elements to each other.

[0026] The sensor element is preferably designed as at least one Hall sensor, or at least one magnetoresistive sensor, or at least one inductive sensor, or at least one Hall sensor and at least one magnetoresistive sensor, or at least one Hall sensor and at least one inductive sensor, or at least one magnetoresistive sensor and at least one inductive sensor.

[0027] The sensor element is suitable for detecting soft magnetic materials, hard magnetic materials, or a combination of both. Examples of soft magnetic materials include alloys based on iron, nickel, and cobalt, as well as soft ferrites such as nickel-zinc or manganese-zinc ferrites. Examples of hard magnetic materials include cobalt-samarium alloys, neodymium-iron-boron alloys, and martensitic steels.

[0028] The incremental element comprises at least one signal path pair with at least one first signal path and at least one second signal path. The first signal path and the second signal path exert at least one distinguishable magnetic effect on the sensor element. The signal path pair has at least one signal path pair length. The first signal path has at least one first signal path length, and the second signal path has at least one second signal path length. The signal path pair length is the sum of the first signal path length and the second signal path length. The first signal path length and the second signal path length are preferably identical. It is also possible for the first signal path length and the second signal path length to be different.

[0029] Depending on the signal path lengths and the signal path pair lengths, a signal path ratio can be defined. The signal path ratio corresponds to the ratio of the first signal path length to the signal path pair length, or the second signal path length to the signal path pair length.

[0030] The incremental element can be designed as a encoder disk with at least one ridge and at least one slot. The ridge and the slot are arranged radially adjacent to each other around a central axis of the encoder disk. The ridge forms the first signal path and the slot forms the second signal path. Alternatively, the ridge can form the second signal path and the slot the first signal path.

[0031] Alternatively, the incremental element can be designed as a perforated disk with at least one through-hole and at least one area without a through-hole. The area without a through-hole forms the first signal path, and the through-hole forms the second signal path, or vice versa. Furthermore, the incremental element can be designed as a pole wheel with at least one permanent magnet having a north pole and a south pole. The permanent magnet is arranged radially around a central axis of the pole wheel. The north pole of the permanent magnet forms the first signal path, and the south pole of the permanent magnet forms the second signal path, or vice versa.

[0032] The sensor element and the incremental element are magnetically coupled across the air gap, which has a specified air gap width. The magnetic coupling between the sensor element and the incremental element depends on the air gap and, in particular, its width. The detection of the first signal path and the detection of the second signal path are influenced by the air gap width. With at least one rotation of the incremental element, either clockwise or counterclockwise, the sensor signal generates at least one sensor signal if the first signal path is detected, if the second signal path is detected, or if both the first and second signal paths are detected.

[0033] The sensor signal exhibits a first signal profile with a first signal duration when the first signal segment is detected, and a second signal profile with a second signal duration when the second signal segment is detected. Consequently, during at least one rotational movement of the incremental element, the sensor signal exhibits, in alternating sequence, the first signal profile and the subsequent second signal profile, or the second signal profile and the subsequent first signal profile. The sum of the first signal duration and the second signal duration corresponds to a signal period. A signal duration indicates the time required to detect a signal segment length. At least one rotational speed can be determined as a function of a signal duration and a signal segment length. A signal period indicates the time required to detect a pair of signal segment lengths.Depending on the signal period and the signal path length, at least one rotational speed can be determined.

[0034] The sensor signal is preferably a square wave signal, a sine wave signal, a triangle wave signal, or a sawtooth wave signal.

[0035] At least one duty cycle can be determined from the sensor signal. The duty cycle is a ratio of the first signal duration to the signal period, or a ratio of the second signal duration to the signal period. If at least one air gap width lies within the previously defined tolerance range, the duty cycle of the first signal duration to the signal period corresponds to the signal path ratio of the first signal path length to the signal path pair length. If at least one air gap width lies within the previously defined tolerance range, the duty cycle of the second signal duration to the signal period corresponds to the signal path ratio of the second signal path length to the signal path pair length. If the air gap width lies outside the previously defined tolerance range, the duty cycle deviates from the signal path ratio.Consequently, the air gap width can be checked depending on the duty cycle and a previously defined limit range.

[0036] At least one duty cycle within the previously defined limit indicates at least one air gap width between the sensor element and the incremental element that is within the previously defined tolerance range. Conversely, at least one duty cycle outside the previously defined limit indicates at least one air gap width between the sensor element and the incremental element that is outside the previously defined tolerance range.

[0037] The previously defined limit range can, for example, cover a value range of -10% to +10% or -15% to +15%, or a similar range. The previously defined tolerance range can, for example, cover a value range of 0.4 mm to 1.6 mm or 0.4 mm to 1.8 mm, or a similar range.

[0038] At the beginning of the process, a first step involves defining at least one determination of at least one rotational speed or at least one specification for determining at least one rotational speed per signal path or per pair of signal paths, depending on at least one selection condition. For example, at least one selection condition could be defined as checking a signal value from at least one human-machine interface of the micromobility vehicle or at least one switch of the micromobility vehicle. Alternatively or additionally, it is possible to define at least one selection condition depending on at least one sensor value from at least one sensor. For example, a longitudinal acceleration of the micromobility vehicle tending towards zero, as well as a longitudinal velocity of the micromobility vehicle tending towards a constant value, could be defined as a selection condition.It is possible to determine the longitudinal acceleration and longitudinal velocity using an acceleration sensor of the micromobility vehicle.

[0039] If the selection condition is met, in a second step of the procedure at least one rotary movement with a constant rotational speed of the incremental element is generated by means of at least one control of the electric drive motor or at least one rotary movement with a constant rotational speed of the wheel. The constant rotational speed can be set during at least one movement of the micromobility vehicle with at least one wheel in surface contact or during at least one stationary movement of the micromobility vehicle with at least one wheel without surface contact. For example, at least one rotary movement with a constant rotational speed of the incremental element can be generated while the micromobility vehicle is supported, rotated 180 degrees, on a saddle and a steering wheel.Alternatively, a wheel of the micromobility vehicle driven by the electric drive motor can be kept in the air.

[0040] In a third step of the procedure, at least one duty cycle is determined from at least one sensor signal of the sensor element of the incremental measuring system. In a fourth step, at least one previously defined limit value is retrieved from at least one data storage device. In a fifth step, the determined duty cycle is compared with the previously defined limit value. Depending on the comparison between the determined duty cycle and the previously defined limit value, a setting for determining the rotational speed is stored in at least one data storage device in a sixth step, or in an alternative sixth step. This setting specifies whether, for at least one subsequent determination of at least one rotational speed, the rotational speed is determined per signal segment or per signal segment pair.If at least one duty cycle lies within the previously defined limit range, the sixth step specifies that at least one rotational speed per signal segment must be determined. If at least one duty cycle lies outside the previously defined limit range, the alternative sixth step specifies that at least one rotational speed per pair of signal segments must be determined.

[0041] In a seventh step, depending on the comparison between the determined duty cycle and the previously defined limit, at least one notification perceptible to human senses is generated. The notification can be visual, audible, or haptic, or a combination of both. For example, at least one human-machine interface of the micromobility vehicle can generate the notification. Furthermore, the notification can contain information about at least one deviation between the determined duty cycle and the previously defined limit, and thus also a deviation between an air gap width and a previously defined tolerance range.The notification allows the system to inform a driver about at least one air gap measurement outside the previously defined tolerance range, automatically schedule a maintenance appointment, or adjust the air gap measurement during maintenance of the micromobility vehicle based on the deviation. The process terminates after the seventh step.

[0042] If the selection condition of the first step is not met, in a second alternative step at least one rotational speed is determined from the sensor signal of the sensor element, taking into account the specification retrieved from a data storage device for determining a rotational speed per signal segment or per pair of signal segments. The procedure is then terminated.

[0043] The control unit comprises means for carrying out the method according to the invention. The control unit can, for example, be designed as a control device (electronic control unit or electronic control module).

[0044] When the control unit is used in a micromobility vehicle or outside of a micromobility vehicle, it is connected to at least one sensor element, at least one electric drive motor, and at least one data storage device. A connection that enables data and signal exchange between the connected devices is such that data and signal exchange between them is possible. For this purpose, each connected device has a corresponding interface. Data transmission and signal transmission can be either wired or wireless. The control unit, the sensor element, the electric drive motor, and the data storage device therefore have interfaces that enable such a connection.

[0045] The data storage device is a non-volatile data storage device such as a read-only memory (ROM) in the form of an electrically erasable, programmable read-only memory (EEPROM) or a flash memory in the form of a NAND flash memory.

[0046] Furthermore, the control unit can be configured to control or regulate the electric drive motor. 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 for regulating the electric drive motor.

[0047] The control unit can be integrated into a housing or into a housing with the electric drive motor. The housing can be mechanically connected to a vehicle frame.

[0048] 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.

[0049] 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 be, for example, a data carrier or a downloadable data stream.

[0050] Exemplary embodiments of the invention are shown in the figures. Specifically, they show: Fig. 1 A schematic representation of a micromobility vehicle with an incremental measuring system according to an exemplary embodiment Fig. 2 A schematic representation of an incremental measuring system according to an exemplary embodiment Fig. 3 A schematic representation of various sensor signals of the incremental measurement system IM from Fig. 2 with different air gap widths Fig. 4 a representation of the process for determining a rotational speed using an incremental measuring system IM from Fig. 1 and Fig. 2 for a micromobility vehicle 1 out Fig. 1

[0051] Fig. Figure 1 shows a schematic representation of a micromobility vehicle 1 according to an exemplary embodiment. The micromobility vehicle 1 is shown here as an example e-bike or pedelec, or in particular as an e-mountain bike. Alternatively, the micromobility vehicle 1 can be designed as a velomobile, cargo bike, e-scooter, Segway, or as another type of micromobility vehicle. The micromobility vehicle 1 comprises a drive system 2. The drive system 2 includes an electric drive motor EM and a crank unit 3 with at least one crank shaft 4, at least one crank arm 5, and at least one pedal 6. The electric drive motor EM and the crank unit 3 can be arranged in the area of ​​the bottom bracket. Power from the rider of the micromobility vehicle 1 can be fed into the drive system 2 via the crank unit.Furthermore, the drive system 2 includes an energy storage device 7, which is electrically and signal-effectively connected to the electric drive motor EM. Additionally, the energy storage device 7 can supply the electric drive motor EM with energy (motor operation) or can be supplied with electrical energy by the electric drive motor EM (generator operation). The micromobility vehicle 1 can therefore be driven either purely by muscle power, purely electrically, or by both muscle power and electrically. Furthermore, at least one rotational movement of a wheel 12 of the micromobility vehicle 1 can be generated by at least one control signal to the electric drive motor EM. The drive system 2, the electric drive motor EM, and the energy storage device 7 are signal-effectively connected to a control unit EC of the micromobility vehicle 1.

[0052] Furthermore, the micromobility vehicle 1 has a steering system consisting of a movable axle 8 and a steering linkage 9. The movable axle 8 is connected to the vehicle frame of the micromobility vehicle 1, as well as to the steering linkage 9 and a wheel 11 of the micromobility vehicle 1. The movable axle 8 can be rotated about its rotationally symmetrical axis by means of the steering linkage 9, thereby steering the wheel 11.

[0053] Furthermore, the micromobility vehicle 1 has at least one acceleration sensor SAx. The acceleration sensor SAx allows the longitudinal acceleration and longitudinal velocity of the micromobility vehicle 1 to be determined. The acceleration sensor SAx is connected to the control unit EC of the micromobility vehicle 1 via a signal-effective connection.

[0054] The handlebar 9 can have at least one human-machine interface (HMI). The HMI is capable of generating at least one notification. The notification can be visual, audible, or haptic. The HMI is connected to the EC control unit of the micromobility vehicle 1 via a signal.

[0055] Furthermore, the micromobility vehicle 1 has a brake 10 on wheel 12. The brake 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). By actuating the brake 10 on wheel 12, rotational movement of the wheel 12 can be reduced or prevented. The brake 10 is connected to the control unit EC via a signal.

[0056] The micromobility vehicle 1 has at least one incremental measuring system IM on wheel 12. The incremental measuring system IM comprises at least one sensor element SE and at least one incremental element IE. The sensor element SE is fixedly attached to a vehicle frame, and the incremental element IM is rotationally fixed to wheel 12. The sensor element SE is connected to the control unit EC and transmits a signal. The incremental measuring system IM can determine at least one rotational speed of wheel 12 when it rotates.

[0057] Fig. Figure 2 shows a schematic representation of the incremental measuring system according to an exemplary embodiment. The incremental measuring system IM comprises at least one sensor element, which is designed as a Hall sensor HS, and at least one incremental element, which is designed as an encoder disk GS. As shown in Fig. As shown in Figure 2a, the encoder disk GS comprises several identical ribs TH and several identical slots TL. The ribs TH and the slots TL are arranged radially adjacent to each other around a central axis MA of the encoder disk GS. The slots TL are formed as trapezoidal material recesses. The material of the encoder disk GS is preferably an alloy based on iron, nickel, and cobalt or a martensitic steel. The ribs TH form identical first signal paths SH, and the slots TL form identical second signal paths SL. A first signal path SH and a second signal path TL adjacent to the first signal path SH form a signal path pair SP. The first signal paths SH and the second signal paths SL have at least one distinguishable magnetic effect on the Hall sensor HS.

[0058] The signal section pair SP has at least one signal section length. The first signal section SH has at least one first signal section length, and the second signal section SL has at least one second signal section length. The signal section length is the sum of the first signal section length and the second signal section length. The first signal section length and the second signal section length are preferably identical. It is also possible for the first signal section length and the second signal section length to be different. Depending on the signal section lengths and the signal section pair length, a signal section ratio can be defined. The signal section ratio corresponds to a ratio of the first signal section length to the signal section pair length, or of the second signal section length to the signal section pair length.

[0059] As in a section view AA in Fig. As shown in Figure 2b, the Hall sensor HS and the encoder disk GS are magnetically coupled via an air gap LT with an air gap width LW. The air gap width LW should lie within a previously defined tolerance range TbLW.

[0060] The encoder disc GS can be set into a rotational movement at a rotational speed N. This rotation can be clockwise or counterclockwise. During rotation of the encoder disc GS, the Hall sensor HS alternately detects a first signal path SH and a second signal path SL, or a second signal path SL and a first signal path SH. When detecting signal paths SH and SL, the Hall sensor HS generates at least one sensor signal.

[0061] Fig. Figure 3 shows a schematic representation of various sensor signals from the incremental measurement system IM. Fig. 2 at different air gap widths.

[0062] The SIG sensor signal can be represented as a periodic square wave signal, as shown in Fig. 3a, Fig. 3b and Fig. 3c, or as a periodic sine wave, as in Fig. 3D, Fig. 3e and Fig. The sensor signal SIG is represented as a signal level V over time t, as shown in Figure 3f. Depending on the air gap width, the sensor signal SIG exhibits an alternating sequence of two signal phases: a first signal phase with at least one first signal level H and a first signal duration dH, and a second signal phase with at least one low signal level N and a second signal duration dL. The first signal phase is generated by the detection of the first signal path SH, and the second signal phase is generated by the detection of the second signal path SL. The sum of the first signal duration dH and the second signal duration dL corresponds to a signal period T. During the signal period T, the Hall sensor HS detects a pair of signal paths SP.

[0063] At least one duty cycle can be determined from the sensor signal SIG. The duty cycle is a ratio of the first signal duration dH to the signal period T, or a ratio of the second signal duration dL to the signal period T.

[0064] For an air gap width within a predefined tolerance range, the duty cycle of the first signal duration dH to the signal period T represents the signal path ratio of the first signal path length to the signal path pair length. Similarly, for an air gap width within a predefined tolerance range, the duty cycle of the second signal duration dL to the signal period T represents the signal path ratio of the second signal path to the signal path pair length. For an air gap width outside a predefined tolerance range, the duty cycle deviates from the signal path ratio. Consequently, the air gap width can be checked depending on the duty cycle and at least one predefined limit range.

[0065] If the air gap is too small, and therefore lies outside a previously defined tolerance range, the first signal path SH will not be detected. Fig. 2 favored and a detection of the second signal section SL from Fig. 2 is disadvantaged. Therefore, the first signal duration dH increases, whereas the second signal duration dL decreases, as in Fig. 3b and Fig. 3e is shown.

[0066] If the air gap is too large, and thus lies outside a previously defined tolerance range, the first signal path SH cannot be detected. Fig. 2 disadvantaged and a recording of the second signal section SL from Fig. 2 is favored. Therefore, the first signal duration dH decreases, whereas the second signal duration dL increases, as in Fig. 3c and Fig. 3f is shown.

[0067] Fig. Figure 4 shows a representation of the procedure for determining a rotational speed using an incremental measuring system IM. Fig. 1 and Fig. 2 for a micromobility vehicle 1 out Fig. 1.

[0068] At the beginning of procedure 100, at least one selection condition CND is checked in a first step 101. For example, it is possible to use at least one selection condition CND as a check of at least one signal value, at least one signal, or at least one human-machine interface (HMI) of the micromobility vehicle 1. Fig. 1 or a switch of the micromobility vehicle 1 off Fig. 1. Alternatively or additionally, it is possible to define at least one choice condition CND depending on at least one sensor value from at least one sensor. For example, it is possible to define a longitudinal acceleration of the micromobility vehicle 1 that tends towards zero. Fig. 1 and a longitudinal speed of the micromobility vehicle 1 tending towards a constant value Fig. 1, to define at least one choice condition CND. The longitudinal acceleration and longitudinal velocity can be determined using an acceleration sensor SAx of the micromobility vehicle 1. Fig. 1 will be determined.

[0069] After the election condition CND has been fulfilled, in a second step 102 of the procedure 100 a rotary movement with a constant rotational speed of an incremental element IM of the micromobility vehicle 1 is performed. Fig. 1 by means of at least one control C of an electric drive motor EM of the micromobility vehicle 1 from Fig. 1 or at least one rotational movement with a constant rotational speed of a wheel 12 of the micromobility vehicle 1 from Fig. 1 is generated. The constant rotational speed during at least one journey of the micromobility vehicle 1 is achieved. Fig. 1 with at least one wheel 12 of the micromobility vehicle 1 having surface contact Fig. 1 or during at least one standstill of the micromobility vehicle 1 from Fig. 1 with at least one wheel 12 of the micromobility vehicle 1 without surface contact Fig. 1 adjustable.

[0070] In a third step 103, at least one sensor signal SIG of a sensor element SE of the micromobility vehicle 1 is used. Fig. 1 at least one duty cycle DT determined.

[0071] In a fourth step 104, at least one previously defined boundary range GbDT is retrieved from at least one data store STO.

[0072] In a fifth step 105, a comparison is made between the determined duty cycle DT and the previously defined limit range GbDT. If the determined duty cycle DT lies within the previously defined limit range GbDT, in a sixth step 106 at least one setpoint VG is defined for at least one subsequent determination of at least one rotational speed N, to determine the rotational speed N for each signal section SH, SL. The setpoint VG is stored in at least one data memory STO. If the determined duty cycle DT lies outside the previously defined limit range GbDT, in an alternative sixth step 116 at least one setpoint VG is defined for at least one subsequent determination of at least one rotational speed N, to determine the rotational speed N for each signal section pair SP. The setpoint VG is stored in at least one data memory STO.

[0073] The procedure 100 is then continued in a seventh step 107. In the seventh step 107, at least one notification MSG perceptible to human senses is generated depending on the comparison of the determined duty cycle DT with the previously defined limit range GbDT from the fifth step 105. The notification MSG can be generated visually, acoustically, or haptically, or visually and acoustically, or visually and haptically, or acoustically and haptically. For example, at least one human-machine interface (HMI) of the micromobility vehicle 1 can be generated from Fig. 1. The MSG notification can be generated. Furthermore, the MSG notification can contain information about a deviation between the determined duty cycle DT and the previously defined limit range GbDT, and thus also a deviation between an air gap width and a previously defined tolerance range. With the information about the deviation, it is possible to inform a driver of the micromobility vehicle 1. Fig. 1. to inform about an air gap width that lies outside the previously defined tolerance range, to automatically schedule a maintenance appointment, or as part of maintenance of the micromobility vehicle 1. Fig. 1. Adjust the air gap width depending on the deviation. The procedure is then terminated.

[0074] If the selection condition CND of the first step 101 is not met, the procedure 100 continues in a second alternative step 112. In the second alternative step 112, at least one rotational speed N is determined from a sensor signal SIG of a sensor element SE, taking into account the specification VG retrieved from the data memory STO, to determine a rotational speed per signal path SH, SL or per signal path pair SP. The procedure 100 is then terminated. Reference sign 1 micromobility vehicle 2 Drive system 3 Crank unit 4. Crankshaft 5 Crankset 6 pedal 7 Energy storage 8 movable axes 9 Steering wheel 10 Brake 11 wheels 12 wheel 100 procedures 101 First Step 102 second step 103 third step 104 fourth step 105 fifth step 106 sixth step 107 seventh step 112 second alternative step 116 sixth alternative step Start of procedure End of procedure C control EM electric drive motor EC control unit SAx accelerometer HMI Human-Machine Interface IM Incremental Measurement System SE Sensor element IE Incremental Element N rotational speed SP signal line pair SH first signal section SL second signal section HS Hall sensor GS sensor disc MS central axis TH Steg SL slot AA Sectional View LT air gap LW air gap width TbLW previously defined tolerance range SIG sensor signal V Signal level H first signal level L second signal level t time dH first signal duration dL second signal duration T Signal period DT duty cycle GbDT previously defined boundary area CND election condition MSG notification STO Data Storage VG specification

Claims

[1] Method for determining at least one rotational speed (N) using at least one incremental measuring system (IM), wherein the incremental measuring system (IM) comprises at least one sensor element (SE) and at least one incremental element (IE), wherein the sensor element (SE) and the incremental element (IE) are magnetically coupled via at least one air gap (LT), wherein the incremental element (IE) comprises at least one signal path pair (SP) with at least one first signal path (SH) and at least one second signal path (SL), wherein the first signal path (SH) and the second signal path (SL) have at least one distinguishable magnetic effect on the sensor element (SE), wherein the sensor element (SE) generates at least one sensor signal (SIG) during at least one rotational movement with at least one rotational speed (N) of the incremental element (IE), wherein at least one duty cycle (DT) is determined from the sensor signal (SIG),wherein at least one duty cycle (DT) lying within a previously defined limit range (GbDT) indicates at least one air gap width (LW) of the air gap (LT) lying within a previously defined tolerance range (TbLW), wherein at least one duty cycle (DT) lying outside the previously defined limit range (GbDT) indicates at least one air gap width (LW) of the air gap (LT) lying outside the previously defined tolerance range (TbLW), wherein for at least one subsequent determination of at least one rotational speed (N) of the incremental element (IE), the rotational speed (N) per signal path (SH, SL) is determined for at least one duty cycle (DT) lying within the previously defined limit range (GbDT), or the rotational speed (N) per signal path pair (SP) is determined for at least one duty cycle (DT) lying outside the previously defined limit range (GbDT). characterized by, that at least one notification perceptible to human senses (MSG) is generated depending on at least one comparison between at least one duty cycle (DT) and the previously defined limit range (GbDT), wherein the notification (MSG) can be generated visually, acoustically or haptically or visually and acoustically or visually and haptically or acoustically and haptically. [2] Method according to claim 1, characterized by , that at least one determination of at least one rotational speed or at least one specification (VG) for at least one determination of at least one rotational speed (N) per signal section (SH, SL) or per signal section pair (SP) is specified depending on at least one selection condition (CND). [3] Method according to claim 1, characterized bythat the previously defined limit area (GbDT) and at least one specification (VG) for at least one determination of at least one rotational speed (N) per signal section (SH, SL) or per signal section pair (SP) can be stored or retrieved in at least one data storage device (STO). [4] Method according to claim 1, characterized by , that at least one air gap width (LW) of the air gap (LT) between the sensor element (SE) and the incremental element (IE) is adjustable depending on at least one comparison between at least one duty cycle (DT) and the previously defined limit range (GbDT). [5] Method according to claim 1, characterized by, that the at least one sensor element (SE) is designed as at least a Hall sensor or at least a magnetoresistive sensor or at least an inductive sensor or at least a Hall sensor and at least a magnetoresistive sensor or at least a Hall sensor and at least an inductive sensor or at least a magnetoresistive sensor and at least an inductive sensor. [6] Method according to claim 1, characterized by that the sensor element (SE) is suitable for detecting soft magnetic materials or hard magnetic materials or soft magnetic materials and hard magnetic materials. [7] Method according to claim 1, characterized by, that the incremental element (IE) can be designed as at least one encoder disk (GS) with at least one bridge (TH) and at least one slot (TL), wherein the bridge (TH) and slot (TL) are arranged radially next to each other around a central axis (MS) of the encoder disk (GS), wherein the bridge (TH) forms the first signal path (SH) and the slot (TL) forms the second signal path (SL). [8] Method according to claim 1, characterized by, that the incremental measuring system (IM) is used for at least one determination of at least one rotational speed (N) of at least one rotatable wheel (11,12) of a micromobility vehicle (1) with at least one electric drive motor (EM), wherein at least one rotational movement with at least one constant rotational speed (N) of the incremental element (IE) can be generated by means of at least one control (C) of the electric drive motor (EM) or at least one rotational movement with at least one constant rotational speed (N) of the wheel (11,12). [9] Method according to claim 8, characterized by, that the constant rotational speed (N) is adjustable during at least one journey of the micromobility vehicle (1) with at least one wheel (11,12) having surface contact or during at least one standstill of the micromobility vehicle (1) with at least one wheel (11,12) without surface contact. [10] Control unit (EC) for a micromobility vehicle (1), characterized by , that at least one electric drive motor (EM) of the micromobility vehicle (1) or at least one sensor element (SE) of the micromobility vehicle (1) or at least one electric drive motor (EM) of the micromobility vehicle (1) and at least one sensor element (SE) of the micromobility vehicle (1) can be connected in a signal-effective manner, and wherein the control device (EC) comprises means for carrying out the method according to one of claims 1 to 9. [11] Computer program product comprising instructions which, when the program is executed by a control device (EC), cause it to execute the method according to any one of claims 1 to 9. [12] Computer-readable medium comprising instructions which, when executed by a control device (EC), cause it to execute the method according to any one of claims 1 to 9. [13] Micromobility vehicle (1) with at least one control unit (EC) according to claim 10.

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