Method for controlling an electric motor for a push-assist operating mode, control unit and two-wheeler

Abstract

Method for controlling an electric motor (111) as a drive motor of a two-wheeler (100), comprising the following method steps • sensor-based detection (220) of pushing the two-wheeler (100), • Capture (240) a user input to activate a push-assist operating mode, and • Generation (250) of a motor torque to drive the two-wheeler (100) in push-assist mode depending on the detected pushing and the user input, • wherein the following step is carried out before the generation (250) of the motor torque, • Display (230) of information for releasing the acquisition (240) of an input depending on the detected pushing to activate the push assist operating mode.

Description

[0001] The invention relates to a method for controlling an electric motor as a drive motor of a two-wheeler for a push-assist operating mode. The invention further relates to a control unit configured to carry out the method according to the invention and to a two-wheeler with this control unit. State of the art

[0002] Two-wheeled vehicles with an electric motor as the drive motor are known, especially e-bikes. In normal operation, the electric motor is preferably controlled based on the pedaling force applied by the cyclist to the pedals of the two-wheeled vehicle or e-bike; for example, the rider's torque is detected by a sensor. Furthermore, a push-assist mode is known to provide power support to the cyclist when pushing the two-wheeled vehicle. The push-assist mode, also simply called push assist, has become an important feature of these often relatively heavy two-wheeled vehicles, as pushing can be difficult, especially on inclines. In push-assist mode, the cyclist receives motor assistance while walking alongside the bicycle, up to a relatively low speed.In other words, while the motor provides power assistance in walk assist mode, the cyclist does not exert any pedal force. A two-stage activation of the walk assist mode, for example by pressing two buttons simultaneously, typically prevents unintentional activation. This could occur, for instance, due to accidental activation on a sloping staircase or during repairs. However, requiring two presses to activate the walk assist mode is not particularly intuitive, leaving some users unsure how to do so.

[0003] Document DE 10 2016 218 374 B3 discloses a control method for generating torque by an electric motor to drive an electric bicycle when the push assist is activated.

[0004] Document DE 10 2016 209 570 B3 discloses a control method for a push assist of an electric bicycle.

[0005] German patent application DE 10 2016 209 560 B3 describes a control method for regulating an electric motor for the push assist function of an electric bicycle. The control method regulates the electric motor based on a detected pitch angle of the electric bicycle around its transverse axis.

[0006] From German patent application JP H11-49 078 A, a device for detecting when a user pushes the vehicle is known, enabling motor assistance. German patent application DE 10 2014 217 758 A1 discloses a drive assist system that uses sensor-acquired data as an activation state for the drive assist. German patent application DE 10 2018 104 664 A1 describes a walking mode for a vehicle, in which the motor assistance is interrupted by sensor data or manual input after activation. Furthermore, German patent application JP 2019-155 962 A discloses an electric bicycle with a push assist function that terminates the motor assistance after a certain period of time.Reference is also made to the publications DE 10 2018 212 636 B3, DE 10 2018 212 453 A1, DE 10 2016 224 314 A1, FR 2 768 991 A1, DE 10 2016 209 570 B3, DE 20 2005 006 684 U1, EP 0 818 386 A1, DE 10 2019 216 075 A1 and JP H09-123 982 A; as well as JP 3 054 234 B2, JP H04 358 988 A, DE 10 2016 209 560 B3 , JP 2019 177 719 A and the operating instructions for the Bosch Purion from 2018.

[0007] The object of the present invention is to simplify the activation of the push-assist operating mode for a cyclist or user. Disclosure of the invention

[0008] The above problem is solved according to the invention in accordance with independent claims 1, 11 and 12.

[0009] The present invention relates to a method for controlling an electric motor as a drive motor for a two-wheeled vehicle. The two-wheeled vehicle is, in particular, an electric bicycle. The control method comprises, as process steps, sensor-based detection of the two-wheeled vehicle being pushed, or detection of the two-wheeled vehicle being pushed by a user by means of a sensor or sensor unit, which preferably includes an accelerometer. In other words, it is advantageously detected when the user is pushing the two-wheeled vehicle while walking. Optionally, the direction in which the user is pushing the two-wheeled vehicle is also detected. The detection of the pushing action is advantageously sensor-based, resulting in automatic detection of the pushing action.In a further step of the process, user input to activate a push-assist mode is detected, particularly via an input device such as a switch, button, touchscreen, or push button. The input is only detected if it is continuous. Continuous input or operation of the input device is recognized, for example, as soon as the input lasts for a period of time greater than or equal to a predefined duration, such as between 1 and 10 seconds. Advantageously, the user input is detected depending on the pushing action or occurs during the pushing action.In other words, in this optional embodiment, the detection of pushing the two-wheeler enables the user input to be registered for activating the push-assist mode. According to the invention, the detection of pushing advantageously occurs after the user input has been registered, and the detection of pushing is advantageously performed depending on the registered input. In other words, in this optional embodiment, the registered user input enables the detection of pushing. Subsequently, a motor torque is generated to drive the two-wheeler, depending on the registered input for activating the push-assist mode and depending on the detected pushing.In other words, the user's input, which activates the push assist mode during a sensor-detected pushing motion, advantageously generates motor torque for the push assist, or activates the push assist itself. The generated motor torque can advantageously be configured, depending on the detected pushing direction, to propel the two-wheeler forward or backward in the direction of travel. Furthermore, the motor torque is advantageously generated based on the detected pushing motion. For example, the generation of motor torque is activated if user input has been previously detected.This allows, for example, the generation of motor torque to be additionally or alternatively interrupted if no pushing of the bicycle is detected or if the bicycle is actively braked by the rider, and / or optionally, the bicycle's speed to be adjusted depending on the detected pushing speed. The advantage of this method is that a single input from the cyclist or user is sufficient to activate the push-assist mode and generate motor torque to support pushing, preventing accidental activation. Furthermore, deactivating the push-assist mode is easily achieved; for example, user input is only registered if the input device is continuously activated.This control method enables easy and intuitive operation, while the possibility of incorrect activation of the push-assist mode is virtually eliminated due to the automated detection of the user or cyclist pushing the bicycle, which is a necessary condition for generating motor torque and activating the push-assist mode. In other words, the control method advantageously represents a two-stage activation of the push-assist mode for generating motor torque: one stage detecting the pushing action and the other capturing the user's input.Not according to the invention is it provided that the push-assist operating mode for generating the motor torque is activated by detecting the user's input and subsequently recognizing the pushing motion, whereby the motor torque is generated to drive the two-wheeler or e-bike, wherein, in particular, continuous detection of the user's input is required to generate the motor torque. Alternatively, it is provided that the push-assist operating mode for generating the motor torque is activated by detecting the pushing motion and subsequently or simultaneously detecting the user's input, whereby the motor torque is generated to drive the two-wheeler or e-bike, wherein, in particular, continuous detection of the user's input is required to generate the motor torque.Particularly preferred is the detection of pushing by means of a sensor unit and a control unit of the two-wheeler's drive unit, and the recording of the user's input by means of an input device or button on a control device on the handlebars of the two-wheeler and / or by means of a display device on the handlebars of the two-wheeler. This has the advantage that even if one of these components of the two-wheeler malfunctions, no engine torque is generated for the push-assist operating mode. This advantageously increases the safety of the two-wheeler's user.

[0010] According to the invention, the user is shown information regarding the release of input for activating the push-assist operating mode, depending on the detected pushing action or during the pushing action. In other words, after the pushing action is detected, the user is shown that the push-assist operating mode can be activated as soon as, or when, user input is detected, whereby the input must be continuous. Advantageously, the information is displayed by means of a display device, for example, arranged on the handlebars of the two-wheeler, and in particular by means of a human-machine interface (HMI).Alternatively or additionally, the information can be displayed by means of lights, which are arranged, for example, on or in the handlebars and / or on or in the frame of the bicycle and / or on or in a button for activating the walk assist function; these lights include, in particular, LEDs. Alternatively or additionally, the information can be displayed by an acoustic signal and / or by means of at least one actuator, the actuator being configured to generate a haptic signal or vibration of the handlebars and / or the frame of the bicycle. This design informs the user and allows for intuitive operation and activation of the walk assist mode.

[0011] In another embodiment, which is not according to the invention, the user is shown information regarding the activation of the push assist mode based on the user's input. Specifically, the user is shown that, following the user's input, the motor torque is generated or the push assist mode is activated by the sensor-based detection of the push. In other words, the user is shown that the push assist mode is activated as soon as, or when, the push is detected, the input must be continuous.The information is advantageously displayed via the display of the display device, for example, arranged on the handlebars of the two-wheeler, and in particular by means of a human-machine interface (HMI). Alternatively or additionally, the information can be displayed by means of lights, which are arranged, for example, on or in the handlebars and / or on or in the frame of the two-wheeler and / or on or in a button for activating the push assist; the lights include, in particular, LEDs. Alternatively or additionally, the information can be displayed by an acoustic signal and / or by means of at least one actuator, wherein the actuator is configured to generate a haptic signal or a vibration of the handlebars and / or the frame of the two-wheeler. This design also informs the user, and operation or activation of the push assist mode is intuitive.

[0012] In a preferred embodiment of the invention, the speed of the two-wheeler is detected in a step prior to the detection of pushing. Pushing is then detected depending on the detected speed; in particular, pushing is only detected at a speed less than or equal to a maximum speed of, for example, 6 km / h. This embodiment prevents the push-assist mode from being erroneously activated during normal operation of the two-wheeler under most driving conditions.

[0013] In a preferred embodiment of the invention, the acceleration of the two-wheeler is detected along a longitudinal axis and / or a transverse axis. Subsequently, pushing is detected as a function of the detected acceleration. Optionally, the direction of pushing is also detected as a function of the detected acceleration. This embodiment offers the advantage that movement of the two-wheeler can be detected even when stationary or at very low accelerations and / or speeds. Push detection as a function of the detected acceleration is preferably performed when a threshold value is exceeded, particularly after filtering a signal from a sensor unit representing the acceleration, and / or by a machine-trained detection method, artificial intelligence, or a trained neural network.This allows, for example, the acceleration profile of a two-wheeler at low speeds, such as on an incline, to be distinguished from the acceleration profile when pushing the two-wheeler, so that pushing is detected automatically and reliably.

[0014] In a particularly preferred embodiment, after the acceleration has been recorded, at least one statistical quantity is determined as a function of the recorded acceleration in the direction of the longitudinal axis of the two-wheeler and / or in the direction of the transverse axis of the two-wheeler, or as a curve of the recorded acceleration. The statistical quantity is, for example, the standard deviation, an average, a variance, or a covariance between two recorded acceleration curves. The statistical quantity, for example, the standard deviation, is advantageously determined for a predetermined time interval, for example, 1 to 10 seconds. Subsequently, in this embodiment, pushing is additionally detected as a function of the at least one determined statistical quantity, for example, the standard deviation, and a threshold value.Pushing is detected particularly when the measured standard deviation exceeds the threshold value during the specified time period. This design has the advantage that even small or slight movements of the bicycle can be recognized as pushing.

[0015] In a further embodiment, the system can detect a change in the direction of the detected acceleration along the transverse axis within a predefined time period. Subsequently, in this embodiment, the detection of pushing is additionally dependent on this detected change in the direction of the detected acceleration along the transverse axis. This embodiment offers the advantage that the user can perform an easy-to-remember and intuitive movement pattern to detect pushing or a desire to push.

[0016] In another embodiment, the rotation of the electric motor's rotor is detected as a backward movement of the two-wheeler along its longitudinal axis. The system then recognizes the pushing motion based on the detected rotor rotation. In particular, the direction of the push is also recognized as a function of the detected rotor rotation. This offers the advantage that, with typical drive systems featuring a motor freewheel in a forward-rotating direction, the movement of the two-wheeler can be detected very quickly and recognized or interpreted as pushing.

[0017] Furthermore, it can be provided in a single step to capture a camera image or a sequence of camera images of at least a part of the two-wheeler's surroundings. The camera can advantageously be arranged on a component of the two-wheeler; for example, the camera is mounted on the handlebars of the two-wheeler with a viewing direction in the direction of travel or forward along the longitudinal axis of the two-wheeler. Subsequently, the pushing motion and / or the direction of pushing is detected based on the captured camera image or sequence of camera images. For example, it can be provided that the pushing motion is detected based on a movement of the two-wheeler determined as a function of the calculated optical flow. The optical flow can be determined as a function of the sequence of camera images.This embodiment of the invention advantageously allows the pushing of the two-wheeler by the user to be detected relatively reliably and quickly.

[0018] Furthermore, in a further embodiment of the invention, it is possible to detect a force exerted by the user or cyclist on the handlebars of the two-wheeler in the direction of the two-wheeler's longitudinal axis. In this embodiment, the pushing action and / or the pushing direction is then recognized depending on the detected force of the user. This embodiment allows for the highly reliable detection of a desired pushing action of the two-wheeler and / or a pushing direction.

[0019] In a further step of the process, the user's pedaling amplitude, in particular cadence and / or rider torque, can be recorded. Pushing is then detected based on this recorded amplitude, with no pushing being detected if the pedaling amplitude is not present. This design reliably prevents incorrect activation of the push assist or the push assist operating mode.

[0020] Preferably, the information regarding the possible activation of the push-assist mode is displayed by adjusting the illumination of a button for the user to activate the push-assist mode. Advantageously, the button illuminates or flashes in color, particularly green, when pushing is detected. This design makes it easy to indicate to the user or cyclist that the push-assist function has been activated.

[0021] The invention also relates to a control unit. The control unit is configured to execute the method according to the invention. In other words, the control unit is set up to carry out the method according to the invention.

[0022] The invention further relates to a two-wheeler with the control unit according to the invention.

[0023] Further advantages will become apparent from the following description of exemplary embodiments with reference to the figures. Fig. 1: Electric bicycle as a two-wheeler Fig. 2: Flowchart of the process as a block diagram Examples of implementation

[0024] In Fig. Figure 1 schematically depicts an electric bicycle as a two-wheeler 100. Alternatively, the two-wheeler 100 could be a motorcycle, where the motorcycle is powered by an electric motor 111. The electric bicycle or two-wheeler 100 in Fig. 1 has a front wheel 101 and a rear wheel 102 as wheels. The two-wheeler 100 in Fig. The assembly 1 comprises a drive unit 110 on a pedal axle 106 or crankshaft, which includes an electric motor 111 as its drive motor. The drive unit 110 includes a control unit 180, which is configured to control the electric motor 111 to generate motor torque for driving the two-wheeler 100 or e-bike. In other words, the control unit 180 is configured to control the electric motor 111, thereby generating motor torque to drive the two-wheeler 100. The pedals 115 are connected to the pedal axle 106 or crankshaft by means of cranks 114 for generating rider torque. The rider torque can be detected as a pedaling input by means of a torque sensor 105 located in the area of ​​the pedal axle 106.Alternatively, the user's pedaling frequency or cadence can be recorded, for example, by means of a speed sensor on the pedal axle 106 and / or on the pedals 115. The pedal axle 106 or crankshaft and the electric motor 111 are connected to an output sprocket 117 by means of a gearbox. The output sprocket 117 is connected, for example, by means of a connecting element 116, such as a chain or a belt, to a hub of the rear wheel 102 as the drive wheel for the propulsion of the two-wheeler 100. It may be provided that at least one speed sensor 107 is arranged on or in the electric motor 111 and / or on the gearbox of the drive unit 110 and / or on the output sprocket 117 and / or on the connecting element 116 and / or on the rear wheel 102 and / or on the front wheel 101.In other words, the speed sensor 107 is configured to detect the rotational speed of a component of the drivetrain of the two-wheeler 100 or the speed of the two-wheeler 100, in particular the rotation or speed and / or direction of rotation of the electric motor 111 of the drive unit 110. The vehicle also has at least one speed sensor 114a and / or 114b and / or 114c. The speed sensor 114a, 114b and / or 114c comprises, for example, a reed sensor 114a on the front wheel 101 or the rear wheel 102, a speed sensor 114c, a satellite-based position sensor 114b and / or a radar sensor. The speed sensor 114a, 114b, 114c is configured to detect the speed of the two-wheeler 100. Preferably the speed sensor 114c is arranged on a wheel hub of the rear wheel 102 and / or on a wheel hub of the front wheel 101.Preferably, but not necessarily, the speed sensor 114c is the rotational speed sensor 107. A battery module 120 is arranged on the two-wheeler 100 to supply energy to the drive unit 110, in particular to supply energy to the electric motor 111. Furthermore, the drive unit 110 comprises an inertial measuring unit or a sensor unit 112 or a sensor. The sensor unit 112 has at least one acceleration sensor. Advantageously, the sensor unit 112 comprises an acceleration sensor for detecting acceleration in the direction of the longitudinal axis 190 of the two-wheeler 100 and an acceleration sensor for detecting acceleration in the direction of the transverse axis 191 of the two-wheeler 100. An input device or a button 130 or a switch for activating and / or deactivating a walk-assist operating mode is also arranged on the handlebar 103 of the two-wheeler 100 or the electric bicycle.The button 130 can comprise a transparent section 131 and a light source 132, wherein the light source 132 is arranged, in particular, behind the transparent section 131 and, for example, comprises a green LED. The two-wheeler 100 further comprises a display device 140 with a display 141. The display device 140 is arranged, in particular, on the handlebars 103 of the two-wheeler 100. The display 141 is configured to show information to the user or cyclist. Alternatively or additionally to the display device 140, at least one actuator 142, for example, a vibration motor or an electric motor with an unbalanced mass, is arranged on the handlebars 103. The actuator 142 arranged on the handlebars 103 is advantageously configured to generate a haptic signal for the user at at least one handlebar grip 104 of the handlebars 103. It may also be provided that a force sensor 160 is arranged on the handlebar 103.The force sensor 160 is configured to detect a force exerted by the user in the longitudinal direction on the handlebar 103. Furthermore, the two-wheeler includes an optional camera unit 150, which is arranged, for example, on the handlebar 103 or the frame 108 of the two-wheeler 100. Advantageously, the camera unit 150 comprises a camera 151 with a longitudinally forward-facing viewing direction. The camera 151 is configured to capture at least a portion of the two-wheeler 100's surroundings as a camera image.

[0025] In Fig.Figure 2 schematically depicts a flowchart of the procedure as a block diagram. In an optional step 201, the speed of the two-wheeler is recorded. In a further optional step 202, the rotation of the rotor of the two-wheeler's electric motor can be recorded, particularly if the rotor's rotation represents a longitudinally backward movement of the two-wheeler 100. Alternatively or additionally, in optional step 203, a camera image of at least part of the two-wheeler's surroundings is captured. Furthermore, it can optionally be provided that, in step 204, a force exerted by the user on the handlebars of the two-wheeler in the direction of the two-wheeler's longitudinal axis is recorded. Additionally, optionally, the user's pedaling amplitude, in particular the cadence and / or rider torque, is recorded in step 205.In optional step 206, the acceleration of the two-wheeler is recorded along its longitudinal axis and / or its transverse axis. A subsequent optional step 210 may detect a change in the direction of the recorded acceleration along the transverse axis within a predefined time period. Alternatively or additionally, step 211 may optionally determine a standard deviation as a function of the recorded acceleration along the longitudinal axis and / or its transverse axis. In step 220, a sensor or sensor unit 112 detects when the user is pushing the two-wheeler. This sensor-based detection of pushing (220) is based, for example, on the recorded speed.The sensor-based detection 220 of pushing is preferably performed alternatively or additionally depending on the detected speed, the detected rotor rotation, the detected camera image, the detected force of the user and / or the detected pedal stroke size of the user and / or the detected acceleration in the direction of the longitudinal axis and / or the transverse axis. For example, in step 220, pushing is detected at a speed of less than or equal to a threshold value of 6 km / h, or, in particular, no pushing is detected if, in addition to a speed of less than or equal to 6 km / h, a pedal stroke size is also detected. Preferably, the sensor-based detection 220 of pushing is performed alternatively or additionally depending on the detected acceleration of the two-wheeler.In particular, it is provided that in step 220, the sliding is additionally detected depending on the determined standard deviation of the detected acceleration and a threshold value for the standard deviation, whereby the sliding is specifically detected when the determined standard deviation exceeds the threshold value. Alternatively or additionally, it may be provided that the sensor-based detection 220 of the sliding is also carried out depending on the detected change in direction of the detected acceleration in the direction of the transverse axis. Particularly preferably, the sensor-based detection of the sliding in step 220 is carried out depending on several detected quantities, for example, depending on the velocity and the acceleration. Subsequently, in the optional step 230, information for enabling an input to activate the sliding assistance operating mode is displayed depending on the detected sliding.The indication 230 is preferably provided by means of a display device 140 or a display 141, by means of a haptic signal generated by an actuator 142, and / or by adjusting the illumination of a button to detect user input for activating the push-assist mode. In step 240, the user input for activating the push-assist mode is detected, for example, by means of the input device or button 130. Optionally, the user input is only detected if the input device or button is continuously actuated. According to the invention, this detection 240 is performed depending on the detected pushing action. In other words, according to the invention, the user input in step 240 is only detected or taken into account if pushing of the two-wheeler was detected in step 220.Not according to the invention, in step 240 the user's input for activating the push-assist mode is first detected, in particular only if the user's input is continuously detected or the input device is continuously actuated. Subsequently, in this alternative, in step 220, after the user's input has been detected, the user's pushing of the two-wheeler is detected by means of a sensor or sensor unit 1.12, depending on the detected user input. In other words, in this alternative embodiment not according to the invention, the order is reversed; that is, in this alternative, the user's input for activating the push-assist mode is a condition for the sensor-based detection of the two-wheeler being pushed.It can be advantageously provided that, after the input has been captured, the user is shown information indicating that pushing the bicycle activates the push assist, thereby generating motor torque. In step 250, motor torque is generated to drive the bicycle based on a user input and the detected pushing action. Thus, step 250 activates the push assist, generating motor force or motor torque to support the user or cyclist while pushing the bicycle. It is also intended that the motor torque is generated based on the detection (220) of the bicycle being pushed. Specifically, it is intended that step 250 is aborted as soon as pushing is no longer detected.In other words, it may be specifically intended that the procedure be carried out repeatedly or continuously.

Claims

[1] Method for controlling an electric motor (111) as a drive motor of a two-wheeler (100), comprising the following method steps • sensor-based detection (220) of pushing the two-wheeler (100), • Capture (240) a user input to activate a push-assist operating mode, and • Generation (250) of a motor torque to drive the two-wheeler (100) in push-assist mode depending on the detected pushing and the user input, • wherein the following step is carried out before the generation (250) of the motor torque, • Display (230) of information for releasing the acquisition (240) of an input depending on the detected pushing to activate the push assist operating mode. [2] Method according to claim 1, wherein the following steps are performed before the capture (240) of the user's input • Detection (201) of a speed of the two-wheeler (100), and • Detection (220) of pushing depending on the detected speed. [3] Method according to any of the preceding claims, wherein the following steps are performed before the capture (240) of the user's input • Detection (206) of an acceleration of the two-wheeler (100) in the direction of a longitudinal axis (190) of the two-wheeler (100) and / or in the direction of a transverse axis (191) of the two-wheeler (100), and . • Detection (220) of pushing depending on the detected acceleration of the two-wheeler (100). [4] Method according to claim 3, wherein the following step is carried out • Determination (211) of a statistical quantity, in particular a standard deviation, as a function of the recorded acceleration in the direction of the longitudinal axis (190) of the two-wheeler (100) and / or in the direction of the transverse axis (191) of the two-wheeler (100), and • Detection (220) of shifting additionally depending on the determined statistical quantity and a threshold value, wherein the shifting is detected in particular when the determined statistical quantity exceeds the threshold value. [5] Method according to one of claims 3 or 4, wherein the following step is carried out • Detection (210) of a change in direction of the detected acceleration in the direction of the transverse axis (191) within a specified time period, and • Detection (220) of the sliding additionally depending on the detected change of direction of the detected acceleration in the direction of the transverse axis (191). [6] A method according to any of the preceding claims, wherein the following steps are carried out • Detection (202) of a rotation of the rotor of the electric motor (111), and • Detection (220) of the pushing motion depending on the detected rotor rotation. [7] A method according to any of the preceding claims, wherein the following steps are carried out • Capture (203) a camera image of at least part of the environment of the two-wheeler (100), and • Detection (220) of pushing depending on the captured camera image. [8] A method according to any of the preceding claims, wherein the following steps are carried out • Detection (204) of a force exerted by the user in the direction of the longitudinal axis of the two-wheeler on a handlebar of the two-wheeler, and • Detection (220) of pushing depending on the detected force of the user. [9] A method according to any of the preceding claims, wherein the following steps are carried out • Recording (205) a user's pedaling speed, in particular a cadence and / or rider torque, and • Detection (220) of pushing depending on the detected step size of the user, whereby in the case of a detected step size, in particular no pushing is detected. [10] Method according to one of the preceding claims, wherein the display (230) of the information is effected by adjusting the illumination of a button for user input to activate the push-assist operating mode. [11] Control unit (180) wherein the control unit (180) is configured to perform a method according to any one of claims 1 to 10. [12] Two-wheeled vehicle (100), in particular an electric bicycle, with a control unit (180) according to claim 11.

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