METHOD FOR PREDICTING A TIME POINT OF A FUTURE EXTREME VALUE IN A TORQUE HISTORY OF A VEHICLE

Description

[0001] The invention relates to a method for predicting a point in time of a future extreme value in a torque curve of a vehicle, in particular a single-track vehicle such as an eBike.

[0002] The invention also relates to a method for shifting a transmission of a vehicle, in particular a single-track vehicle such as an e-bike,

[0003] The invention further relates to a vehicle, in particular a single-track vehicle such as an e-bike,

[0004] Although generally applicable to signal waveforms, the following invention is explained using torque waveforms in eBikes as an example. State of the art

[0005] E-bikes include a support drive that amplifies the torque applied to the e-bike by a rider, thus assisting the rider while riding.

[0006] The e-bikes can be equipped with a transmission, particularly an electric or automatic transmission. In an automatic transmission, the gear changes automatically depending on the applied torque or speed. If a rider generates high torque during shifting, which is further amplified by the drive unit, the resulting torque can lead to malfunctions or friction in the transmission. The same applies to manual transmissions if the rider generates high torque during shifting. Document US2021 / 061414A1 discloses a method for improving shifting by using a control unit designed to determine an acceptable shift time interval based on torque and cadence. Disclosure of the invention

[0007] In one embodiment, the present invention provides a method for predicting a time of a future extreme value in a torque curve of a vehicle, in particular a single-track vehicle such as an e-bike, comprising the steps of: Determining a torque value at several points in time, determining an extreme value of the determined torque values ​​at each point in time, measuring an elapsed time and / or an angle traveled by a pedal of the vehicle since the point in time at which the extreme value was determined, determining a period of the torque curve, and predicting at least one point in time of a future extreme value based on the determined period as well as the measured time and / or the angle traveled.

[0008] In one embodiment, the present invention provides a method for shifting a transmission of a vehicle, in particular a single-track vehicle such as an e-bike, comprising the steps of: Predicting a time at which the torque applied to the vehicle is minimal, using a method according to any one of claims 1-7, and shifting the vehicle's transmission at the predicted time. In one embodiment, the present invention provides a vehicle, in particular a single-track vehicle such as an e-bike, onto which a rider can apply torque, resulting in a regular torque curve, comprising: A torque sensor configured to determine a torque value at several points in time; a determining device configured to determine an extreme value of the determined torque values; a measuring device configured to measure an elapsed time and / or an angle traveled by a pedal of the vehicle since the time at which the extreme value was determined; a determining device configured to determine a period of the torque curve; a predicting device configured to predict at least one point in time of a future extreme value based on the determined period as well as the measured time and / or the angle traveled.

[0009] One of the advantages gained from this is that the next possible moment when the driver generates minimum torque can be easily calculated. Another advantage is that the calculation can be performed quickly and efficiently. A further advantage is that both maximum and minimum torque values ​​can be predicted.

[0010] The term "extreme value" is to be understood in the broadest sense and refers, particularly in the claims, preferably in the description, to a value in a curve, for example a torque curve, which is the smallest or the largest value within a certain time window. Specifically, the extreme values ​​are the maxima and minima, i.e., the peaks and troughs, of a sinusoidal curve where the rate of change of the curve is approximately zero.

[0011] The term "period" is to be understood in the broadest sense and refers, particularly in the claims, preferably in the description, to the time required for a pedal of the vehicle to complete one full revolution. Specifically, the torque curve of the pedals during the period exhibits two peaks and two troughs, since a minimum torque is generated at the top and bottom dead centers of the pedals, respectively.

[0012] Further features, advantages and further embodiments of the invention are described below or become apparent therein.

[0013] According to an advantageous embodiment of the invention, the angle traveled by the vehicle's pedal and / or the period are measured using a speed sensor. With a regular torque curve, successive extreme values ​​are offset by half a period of the curve or half a pedal rotation. Thus, the period can be used to determine the next extreme value. The period and / or the angle traveled can be determined using a speed sensor, since the period corresponds to the inverse of the rotational speed and the angle traveled corresponds to the integral of the rotational speed over time. An advantage of this is that the period and the angle traveled can be determined easily.

[0014] According to an advantageous embodiment of the invention, the elapsed time is measured using a timer, which is reset when a new extreme value is determined. A timer, for example, can be used to measure the time since the last extreme value. This timer is reset each time a new extreme value is determined. Thus, the timer always displays the time since the last determined extreme value. An advantage of this is that the time can be determined efficiently.

[0015] According to an advantageous embodiment of the invention, the period is determined by comparing the times of two specific extreme values. If two or more extreme values ​​have already been determined, the period can be calculated from these, since two identical extreme values—that is, two minima or two maxima—occur with a periodic signal offset by half a period. An advantage of this is that the period can be determined without a speed sensor.

[0016] According to an advantageous embodiment of the invention, the prediction of at least one point in time of the future extreme value is only performed if the measured time exceeds a threshold. It is possible that several new extreme values ​​are determined within short time intervals during the extreme value determination process, as the torque continuously increases or decreases. Furthermore, local extreme values ​​in the torque curve can occur due to irregularities in the driving behavior. In this case, the prediction process can be suspended until an extreme value is determined that is not replaced for a certain period and is therefore highly likely to be a true minimum or maximum. An advantage of this is that unnecessary calculations for predicting the next point in time can be reduced.Furthermore, a potential extreme value can be considered a definite extreme value if the time elapsed since its measurement exceeds the threshold. Therefore, the timer can be reset from this point onward, and the next extreme value can be determined.

[0017] According to an advantageous embodiment of the invention, to determine the extreme value, it is checked whether a currently measured torque value is greater or less than a current extreme value. The applied torque can be measured continuously. If, for example, a minimum torque is to be determined, the current minimum can be stored. Subsequently, each newly measured torque value is compared with the current minimum. If the torque value is less than the current minimum, this torque value is set as the new minimum. In this way, an extreme value can be determined quickly.

[0018] According to an advantageous embodiment of the invention, the times of the next and the next-but-one extreme values ​​are predicted. An advantage of this is that the next-but-one time can be used if an action, for example, shifting the transmission, cannot be carried out before the next possible extreme value due to insufficient time.

[0019] According to an advantageous embodiment of the invention, the vehicle comprises a switching device configured to engage a transmission of the vehicle at a time when the predictive device has forecast a minimum. An advantage of this is that the vehicle is shifted at a time when the torque generated by the driver is at its minimum.

[0020] Further important features and advantages of the invention will become apparent from the dependent claims, the drawings and the accompanying description of the figures.

[0021] It is understood that the features mentioned above and those to be explained below can be used not only in the combinations specified, but also in other combinations or on their own, without leaving the scope of the present invention.

[0022] Preferred embodiments and configurations of the present invention are shown in the drawings and are explained in more detail in the following description.

[0023] This is shown in schematic form Figure 1 shows a flowchart with steps of a method according to an embodiment of the present invention, Figure 2 shows a torque curve according to an embodiment of the present invention, Figure 3 shows steps of a method according to an embodiment of the present invention, and Figure 4 shows a vehicle according to an embodiment of the present invention.

[0024] Figure 1Figure 1 shows in schematic form a flowchart with steps of a method according to an embodiment of the present invention.

[0025] In a first step, S1, a torque value is determined at several points in time. For example, the torque values ​​can be determined using a torque sensor. The torque values ​​correspond to the torque applied by a driver to the vehicle's pedals. By measuring the torque at multiple points in time, a torque value profile can be generated.

[0026] In a further step S2, an extreme value of the measured torque values ​​is determined for each point in time. For example, a minimum torque value is determined. For this, the most recently measured torque value is compared with the current minimum, and if the most recently measured torque value is lower than the current minimum, this torque value becomes the new minimum. Since a rider's pedaling torque is approximately sinusoidal due to the pedal movement, the extreme values ​​within the torque curve can be determined in this way.

[0027] In a further step S3, the elapsed time and / or the angle traveled by a vehicle pedal since the time the extreme value was determined is measured. For example, a timer that continuously counts the seconds is used for this purpose. In step S2, a decision 101 is made for this. Whenever a new extreme value is determined in step S2, the timer is reset 102. In this way, the elapsed time since the last determined extreme value is always determined. Alternatively or additionally, in step S3, the angle traveled by a vehicle pedal can be determined using a speed sensor. For this, the current rotational speed of the pedals is measured, and the measured values ​​are integrated over time. Determining the angle traveled is particularly advantageous if the rotational speed of the pedals is not constant but non-stationary.The angle traveled can be reset analogously to the elapsed time whenever a new extreme value is determined.

[0028] In a further step, S4, the period of the torque curve is determined. The period can be determined, for example, using the speed sensor, since the period is the inverse of the rotational speed. It is also possible to determine the period based on measured extreme values. The sinusoidal torque curve generated by the pedals has two maxima and two minima per pedal revolution, i.e., two upper and two lower extreme values. Therefore, the period is twice the time between two consecutive maxima or minima.

[0029] In a further step S5, at least one point in time of a future extreme value is predicted based on the determined period as well as the measured time and / or the angle traveled. The torque curve exhibits two minima and two maxima per period. Therefore, the time at which the next minimum or maximum of the torque curve will occur can be estimated using the following formula: dt min = T 2 − dt This includes: dt min : Time until the next extreme value ( for example minimum ) T: Period dt: elapsed time since the last extreme value

[0030] It is also possible to estimate the next-but-one extreme value if more time is needed: dt min 2 = T − dt This includes: dt min2 : Time until the next extreme value (e.g., minimum)

[0031] It is also possible to calculate the time of the next extreme value based on the angle traveled by the pedal, using the formula: dt min = T 2 − φ ∗ T this is : φ : Angle traveled by a pedal since the last extreme value

[0032] It is possible to suspend the calculation of the time of the next possible extremum as long as the elapsed time since the last extremum is less than a threshold. This prevents local extrema from being used for time calculations. For example, it can be required that the elapsed time be at least 50 ms, preferably at least 100 ms, and particularly at least 200 ms. It is also possible that the elapsed time must have reached at least one-sixth of the period, preferably one-quarter of the period, and particularly at least one-third of the period.

[0033] Figure 2 The figure shows in schematic form a curve of a torque according to an embodiment of the present invention.

[0034] The graph shows a curve 201 of the torque generated by a driver of a single-track vehicle. The X-axis 202 represents time in seconds and the Y-axis 203 represents torque in Nm. Initially, the torque 201 decreases until it reaches a minimum 204 at time T_0. The next minimum 205 is therefore expected after half a period 207 at time T_min, and the next minimum 206 after a full period 207 at time T_min2.

[0035] However, at time T_0 of minimum 204, it is not yet definitively established that minimum 204 is indeed the global minimum and not a local minimum. Therefore, a timer is started that is reset each time a new minimum is found. At time T_0 of minimum 204, the timer is consequently reset one last time and counts the seconds since time T_0. As soon as a time threshold of 208 is exceeded, it is definitively established that minimum 204 is indeed the global minimum. Here, the threshold of 208 corresponds to one-quarter of the period of 207.

[0036] Thus, at any given time T_1 - in Figure 2Let T_1 be the example time at which the threshold value 208 is exceeded – the time T_min of the next minimum 205 can be determined. This is expected after half a period 207 minus the time dt already elapsed since time T_0 of the minimum 204. The elapsed time dt corresponds to the difference T_1 - T_0. Similarly, the next minimum 206 is expected after a full period 207 minus the time dt already elapsed. Thus, dt_min remains until the next minimum torque 205, and dt_min2 remains until the next minimum 206.

[0037] Figure 3 shows in schematic form the steps of a method according to an embodiment of the present invention.

[0038] By means of the in Figure 2 The method shown allows for optimal shifting of a vehicle's transmission.

[0039] For this purpose, in step S6, a time is predicted at which the torque applied to the vehicle is at its minimum. This time can be determined in particular according to steps S1 to S5. Figure 1 to be determined.

[0040] In a further step, S7, the vehicle's transmission is shifted at the predicted time.

[0041] It is also conceivable that a maximum is predicted and that the vehicle is not shifted at the predicted time, but only after and / or before, so that the applied torque is lower.

[0042] Figure 4 The figure shows in schematic form a vehicle according to an embodiment of the present invention.

[0043] Shown is a vehicle 1, here in the form of an e-bike, with a drive unit 2 and a transmission 3. The transmission 3 can be an automatic transmission and / or an electrically shiftable transmission. Using the vehicle 1, a time can be determined at which the transmission 3 can be shifted, as a minimum torque is expected to be present at this time. For this purpose, the vehicle 1 has: A torque sensor 4, configured to determine a torque value at several points in time; a determining device 5, configured to determine an extreme value of the determined torque values; a measuring device 6, configured to measure an elapsed time and / or an angle traveled by a pedal 7 of the vehicle 1 since the time at which the extreme value was determined; a determining device 8, configured to determine a period of the torque curve; a predicting device 9, configured to predict at least one point in time of a future extreme value based on the determined period as well as the measured time and / or the angle traveled.

[0044] The vehicle is specifically trained to perform steps S1 to S5 according to Figure 1 Furthermore, the vehicle is trained to perform steps S6 to S7 according to Figure 2 to carry out.

[0045] In summary, at least one embodiment of the invention has at least one of the following advantages and / or at least one of the following features: Determining the point in time at which an applied torque will be at its minimum. Simple and efficient timing calculation. Reduced wear during vehicle shifting.

[0046] Although the present invention has been described using preferred embodiments, it is not limited to these, but can be modified in many ways.

Claims

1. Method for predicting a time of a future extreme value (205) in a torque profile (201) of a vehicle (1), in particular a single-track vehicle (1) such as an ebike, comprising the steps of: - determining (S1) a torque value at multiple times, - identifying (S2) an extreme value (204) in the determined torque values at each time, - measuring (S3) an elapsed time and / or an angle covered by a pedal of the vehicle since the time at which the extreme value (204) was identified, - determining (S4) a period duration (207) of the torque profile (201), and - predicting (S5) at least one time of a future extreme value (205) on the basis of the determined period duration (207) and the measured time and / or the covered angle.

2. Method according to Claim 1, wherein the measurement (S3) of the angle covered by the pedal of the vehicle and / or the determination (S4) of the period duration (207) is carried out by means of a speed sensor.

3. Method according to either of Claims 1-2, wherein the measurement (S3) of the elapsed time is carried out on the basis of a timer, the timer being reset when a new extreme value (204) is identified.

4. Method according to one of Claims 1-3, wherein the period duration (207) is determined on the basis of a comparison of the times of two identified extreme values (204).

5. Method according to one of Claims 1-4, wherein the at least one time of the future extreme value (205) is predicted only if the measured time is greater than a threshold value (208).

6. Method according to one of Claims 1-5, wherein identifying (S2) the extreme value (204) involves checking whether a currently determined torque value is greater than or less than a current extreme value.

7. Method according to one of Claims 1-6, wherein the times of the next extreme value (205) and the next-but-one extreme value (206) are predicted.

8. Method for shifting a gear mechanism (3) of a vehicle (1), in particular a single-track vehicle (1) such as an ebike, comprising the steps of: - predicting a time at which a torque applied to the vehicle is at a minimum on the basis of a method according to one of Claims 1-7, and - shifting the gear mechanism (3) of the vehicle (1) at the predicted time.

9. Vehicle (1), in particular a single-track vehicle (1) such as an ebike, to which a rider can apply a torque such that a regular torque profile (201) arises, comprising: a torque sensor (4) designed to determine a torque value at multiple times, an identification device (5) designed to identify an extreme value (204) in the determined torque values, a measuring device (6) designed to measure an elapsed time and / or an angle covered by a pedal (7) of the vehicle (1) since the time at which the extreme value (204) was identified, a determination device (8) designed to determine a period duration (207) of the torque profile, a prediction device (9) designed to predict at least one time of a future extreme value (205) on the basis of the determined period duration (207) and the measured time and / or the covered angle.

10. Vehicle (1) according to Claim 9, comprising a shifting device designed to shift a gear mechanism (3) of the vehicle (1) at a time at which the prediction device (9) has predicted a minimum.