STROLLER FRAME, STROLLER AND COMPUTER-READABLE STORAGE MEDIUM

Abstract

The invention relates to a stroller frame, comprising a sensor unit for capturing sensor data and a drive unit comprised of a computing unit, which is designed to switch the drive unit between a driving state and a non-driving state according to the time curve of the sensor data.

Claims

1. A stroller frame, comprising: a sensor unit for capturing sensor data at a sampling frequency; and a drive unit; and a computing unit coupled to the sensor unit and coupled to the drive unit, wherein the computing unit is configured to switch the drive unit between a driving state and a non-driving state as a function of a comparison of the sensor data and a tolerance interval.

2. The stroller frame according to claim 1, wherein the computing unit is configured to determine a reference value based on a temporally contiguous subset of the sensor data.

3. The stroller frame according to claim 2, wherein the reference value corresponds to a mean value, a trimmed mean, a harmonic mean, or a weighted harmonic mean.

4. (canceled)

5. The stroller frame according to claim 1, wherein the sensor data corresponds to a force or a torque.

6. The stroller frame according to claim 1, wherein the computing unit is configured to switch the drive unit to the non-driving state if fewer than a predetermined number of temporally contiguous measured values of a subset of the sensor data are not within the tolerance interval and configured to switch the drive unit to the driving state if a predetermined number of the temporally contiguous measured values of the subset are within the tolerance interval.

7. The stroller frame according to claim 1, wherein the computing unit is configured to switch the drive unit to the non-driving state if a statistical measure of the spread of the measured values of the sensor data is within the tolerance interval and configured to switch the drive unit to the driving state if the statistical measure of the spread of the measured values is outside the tolerance interval.

8. The stroller frame according to claim 1, wherein a temporally contiguous subset of the sensor data covers at least one interval, wherein each interval includes at least two measured values, wherein at least one of the at least two measured values corresponds to the driving state of the drive unit, and wherein at least one of the at least two measured values corresponds to the non-driving state of the drive unit, wherein the computing unit is configured to switch the drive unit to the non-driving state if fewer than a predetermined number of measured values of a subset of the sensor data are not within the tolerance interval and configured to switch the drive unit to the driving state if the predetermined number of measured values of the subset are within the tolerance interval.

9. The stroller frame according to claim 1, wherein a temporally contiguous subset of the sensor data covers at least one interval, wherein each interval includes at least two measured values, wherein at least one of the at least two measured values corresponds to the driving state of the drive unit, and wherein at least one of the at least two measured values corresponds to the non-driving state of the drive unit, wherein the computing unit is configured to switch the drive unit to the non-driving state if a statistical measure of the spread of the measured values of the subset recorded in the non-driving state is within the tolerance interval and configured to switch the drive unit to a driving state if the statistical measure of the spread of the measured values of the subset recorded in the non-driving state is outside the tolerance interval.

10. The stroller frame according to claim 1, comprising a pusher portion configured for pushing the stroller frame.

11. The stroller frame according to claim 10, wherein the sensor unit is coupled to the pusher portion.

12. The stroller frame according to claim 1, wherein the drive unit comprises one or both of a braking device and an electric motor.

13. The stroller frame according to claim 1, comprising at least three wheels, wherein the drive unit is configured to drive or lock at least one of the at least three wheels.

14. The stroller frame according to claim 1, comprising a framework having one or both of a pusher portion and at least three wheels.

15. The stroller frame according to claim 1, further comprising a framework coupled to a pusher portion by a connecting element or by a connecting portion, wherein the sensor unit is coupled to the connecting element or the connecting portion.

16. The stroller frame according to claim 15, wherein the framework includes at least one hinge portion, wherein the pusher portion is configured to rotate about the hinge portion.

17. The stroller frame according to claim 16, wherein the sensor unit is arranged in the hinge portion.

18. The stroller frame according to claim 17, wherein the framework is configured to have an unfolded configuration and a folded configuration.

19. The stroller frame according to claim 18, wherein the sensor unit is communicatively or electrically connected to the drive unit or the sensor unit is communicatively or electrically connected to the computing unit in the unfolded configuration and wherein the sensor unit is decoupled from the drive unit or the computing unit in the folded configuration.

20. A stroller comprising a stroller frame according to claim 1.

21. A computer-readable storage medium, containing instructions which cause at least one processor to implement the following when the instructions are executed: accessing sensor data; determining a reference value for the sensor data; accessing a measured value; and determining a control command for a drive unit of a stroller using the sensor data and the reference value.

22. A method for determining a control command, comprising: accessing sensor data; determining a reference value for the sensor data; accessing a measured value; determining a control command for a drive unit of a stroller using the sensor data and the reference value.

23. The method for determining a control command according to claim 22, wherein the control command corresponds to an instruction for switching to a non-driving state or a braking state if fewer than a predetermined number of measured values of a subset of sensor data are not within a tolerance interval around the reference value or if all the measured values of the subset or a statistical measure of the spread of the measured values of the subset is within the tolerance interval around the reference value.

24. The method for determining a control command according to claim 22, wherein the control command corresponds to an instruction for a driving command if at least a predetermined number of measured values of sensor data or at least one measured value of a subset or a statistical measure of the spread of the measured values of the subset of sensor data is outside a tolerance interval around the reference value.

25. A computer-readable storage medium, containing instructions which cause at least one processor to implement a method according to claim 22 when the instructions are executed.

Description

[0077] The invention will be explained in greater detail below on the basis of exemplary embodiments. In the figures:

[0078] FIG. 1 shows a schematic illustration of a stroller frame;

[0079] FIG. 2 shows a schematic illustration of different possible arrangements of sensor units;

[0080] FIG. 3 shows a graph displaying exemplary sensor data;

[0081] FIG. 4 shows a further graph displaying sensor data in another exemplary embodiment; and

[0082] FIG. 5 shows a flow diagram of a method for determining a control command.

[0083] Hereinbelow, the same reference signs will be used for parts that are identical or that have the same function.

[0084] FIG. 1 shows a stroller 1, which has four wheels 2. Two front wheels 2 are connected to the stroller 1 via respective wheel mounts 3 with a front wheel suspension 18. In the front region of the stroller 1, a front wheel strut 19 is arranged between the wheel mounts 3 in order to stabilize the wheels 2 on the stroller 1.

[0085] The wheel mounts 3 of the front wheels 2 are connected to an adjusting device 15 via a front wheel suspension 18. The adjusting device 15 is arranged above the front wheels 2 and offset toward the rear. Also arranged on the adjusting device 15 is a rear wheel suspension 17, on which two rear wheels are arranged on a rear wheel axle 24. A parking brake 20, which is designed such that it can be operated by a foot, is arranged approximately in the middle of the rear wheel axle. The parking brake 20 is designed to lock the rear wheels. These can only be brought back into motion again by releasing the parking brake 20.

[0086] In the exemplary embodiment shown, two electric motors 21 for driving the rear wheels are arranged at the ends of the rear wheel axle 24. In other exemplary embodiments, however, it is also conceivable that a single motor drives both wheels via a shaft and/or a transmission.

[0087] In the exemplary embodiment shown in FIG. 1, the rear wheel axle 24 is designed as a hollow cylinder; arranged in the rear wheel axle 24 is an accumulator 23, which is electrically connected to the electric motors 21. Alternatively, the rear wheel axle 24 may also be designed as a strut, and the accumulator 23 may be designed to lie therebelow, even partially. Control electronics may additionally be arranged in or on the rear wheel axle 24, which control electronics are designed to control the functions of the motors 21.

[0088] Also arranged on the adjusting device 15 are retaining devices 25, which are designed to receive an accommodating means (for example a seat shell, a seat unit or a carrycot).

[0089] The adjusting devices 15 are connected to each other via a transverse strut 16 in order to ensure the stability of the device as a whole. Also arranged on the adjusting devices 15 are pusher receiving devices 26, which extend upward and rearward at an angle and are connected to a pusher device via connecting elements 14. The pusher device consists of two side struts 13, 13′, which are displaceably arranged in the pusher receiving device 26. The side struts 13, 13′ can be fixed in position via the connecting elements 14. Arranged at the end of the side struts 13, 13′ is a pusher portion 12, onto which a user can grip for pushing the stroller 1.

[0090] FIG. 2 shows different possible ways of arranging sensor units 30, 30′, 30″, 30′″ on the stroller 1. For instance, FIG. 2 shows a first sensor region 31, which in the exemplary embodiment shown comprises the pusher portion of the stroller 1. Force sensors 30, 30′ may be arranged in the first sensor region 31. The force sensor 30 may be a sensor which is designed to measure a force. The force sensor 30 therefore outputs a signal that can be converted into a force.

[0091] In the exemplary embodiment shown, the force sensor 30 is arranged in the first sensor region 31 in the pusher portion of the stroller 1 in such a way that an interaction with a user of the stroller 1 can be detected. In one exemplary embodiment, the force sensor 30 is integrated in the pusher portion 12, with a contact surface of the force sensor 30 being oriented such as to point toward the operator of the stroller 1.

[0092] Besides mounting a sensor unit 30 in the pusher portion, it is also possible, in a further exemplary embodiment, to arrange force sensors 30′ in a connecting region where the pusher portion 12 is connected to side struts 13, 13′ of the stroller 1. In this case, the pusher portion 12 may be displaceably arranged in the side struts 13, 13′ and may be fixed in position via a fastening element or connecting element 14′. In order to measure forces applied to the pusher portion 12 by a user, a sensor unit, for example a force sensor 30′, may be arranged in the connecting element 14′. A force sensor 30, 30′ may also be designed in an elongate manner and may thus cover both a region of the pusher portion 12 and also of the connecting region.

[0093] FIG. 2 also shows, in a superimposed manner, a second exemplary embodiment in which a sensor unit 30″ is arranged in a connecting element of the side struts 13, 13′.

[0094] In another exemplary embodiment, a sensor unit 30′″ is arranged in a third sensor region 33 or 33′ on the adjustment device 15. This is preferably a torque sensor 30′″. The torque sensor 30′″ is designed to measure a torque caused by a force exerted on the pusher portion 12 or the side struts 13, 13′ by the user.

[0095] Arranged in the rear wheel axle 24 is a computing unit 34, which is communicatively connected to the sensor units 30, 30′, 30″, 30′″. The computing unit 34 is designed to receive and to process sensor data generated by the sensor units 30, 30′, 30″, 30′″. The processing of the data is shown in detail in FIGS. 3 and 4.

[0096] FIG. 3 shows a signal curve of a force sensor 30, 30′, 30″, which is illustrated by a force diagram 40 over time. The time T[s] is plotted on the X axis, and the force F is plotted on the Y axis. A plurality of measured values 43, detected by a sensor unit 30, 30′, 30″, are plotted on the force diagram 40. The measured values 43 together form sensor data 41.

[0097] The times t.sub.0, t.sub.0+1, t.sub.0+2 and t.sub.1 are plotted on the X axis. In order to ascertain whether a person has his hand on the stroller 1, the computing unit 34 is designed to consider a temporally contiguous range of measured values 42. By way of example, FIG. 3 shows a subset of sensor data 42 for a period of time of 0.5 seconds.

[0098] In order to determine whether a current measured value 43′ at the time t.sub.1 indicates an interaction of a user with the stroller 1, a reference value F1 is calculated for the measured values 42 situated in a time interval before the measured value 43′, said reference value indicating a mean of the sensor values in the time interval. In addition, a tolerance interval 44 is set around the reference value F1. In the exemplary embodiment of FIG. 3, the tolerance interval 44 is set as ±30 Newtons in relation to the reference value F1.

[0099] When processing the measured value 43′, it is then checked whether this measured value is within the tolerance interval 44. As shown in FIG. 3, the current measured value 43′ is outside the tolerance interval 44. This means that the force has significantly increased in comparison to the preceding values. From this, it can be deduced that a user is interacting with the stroller 1. The measured value 43′ thus indicates that the stroller 1 is being pushed or held by a person.

[0100] The computing unit 34 described in connection with FIGS. 1 and 2 is designed to switch a motor 21 to a driving state in response to the finding that the measured value 43′ lies outside the tolerance interval 44. This means that the motor drives a stroller frame or a stroller 1.

[0101] In other embodiments which require a plurality of measured values (for example 2 or 3 or 5 measured values) of a subset outside the tolerance interval, the same data could lead to the motor being switched into a non-driving state. Essentially, however, the following applies: By visualizing a force curve belonging to the measured values, it can be seen that if, for example, the sampling frequency is tripled, more than one measured value, probably around 3 measured values, will lie outside the tolerance interval. It then makes sense either to extend the tolerance range or to set the first predetermined number to a value greater than 1.

[0102] In another exemplary embodiment, the computing unit 34 checks whether the measured values 42 are spreading out. This means that the computing unit is designed to calculate a statistical measure of the spread. In the example of FIG. 3, the computing unit 34 may be designed to calculate the variance of the measured values 42. If the calculated variance is outside a tolerance range, the motor 21 will be switched to the driving state by the computing unit 34. In the last-mentioned example, the switching therefore depends not on one single measured value, but rather on the ratio between the measured values in an interval. As a result, a more robust detection of the user interaction can be carried out.

[0103] FIG. 4 shows an example in which the motor 21 will be switched to a driving state. FIG. 4 likewise shows a force diagram 41, in which forces are plotted on the Y axis and times are plotted on the X axis. A number of measurement points 43 are shown in the force diagram 41. As already described in connection with FIG. 3, a reference value F1 is determined for a specified time interval prior to a measured value 43′ currently being measured. In the exemplary embodiment shown in FIG. 4, the time interval is 0.4 seconds. The sampling frequency at which the sensors record the measured values 43 is 20 Hz. Similar to the description of FIG. 3, a tolerance interval 44′ is set around the reference value F1. In the exemplary embodiment of FIG. 4, the limits of the tolerance interval 44′ are selected in such a way that they correspond to ±20% of the value of the reference value F1. The tolerance interval therefore adapts dynamically to the reference value F1.

[0104] In the exemplary embodiment shown in FIG. 4, the measured value 43′ currently being measured lies within the tolerance interval 44′. However, (at least) one value in the time interval lies outside the tolerance interval, and therefore the computing unit 34 determines that the motor must be switched to a driving state since a sufficiently variable force and/or a sufficiently variable torque is acting on the sensor unit, so that it is highly likely that a person is interacting with the stroller 1.

[0105] In a manner analogous to the example described above, the computing unit 34 may also calculate whether the variance of the measured values 42 of an interval lies within a tolerance interval 44′. The computing unit 34 is designed to switch the motor to a non-driving state or braking state if the variance of the measured values in a time interval lies within a tolerance interval 44′.

[0106] In another exemplary embodiment, which is not shown, it is conceivable that the sensor unit is designed to detect a force or a torque at a frequency of 50 Hz. After a certain number of measurements, for example after 5 measurements (in general: after n measurements, where n should be between 2 and 100 or between 2 and twice the measurement frequency specified in Hertz; in the context of this application, it is provided that every single integer value n between 2 and 100 and every integer value between 2 and twice the measurement frequency specified in Hertz is covered by this disclosure), the power to the motor 21 is interrupted for one measurement. Once measured values have been recorded without power to the motor 21 in at least 5, preferably 3, intervals, a mean value (for example the arithmetic mean) of the values in the non-powered state is formed. If at least a first predetermined number of measured values in the non-powered state do not lie outside a tolerance interval around the mean value (the arithmetic mean), i.e. a reference value, in particular if all the measured values in the non-powered state lie within a tolerance interval around the mean value, then the motor 21 is switched to a non-driving state or braking state.

[0107] If at least a first predetermined number of measured values, in particular at least one value, lie(s) outside the tolerance interval, for example ±25 Newtons, then it is ascertained that it is highly likely that a user is interacting with the stroller 1, and the motor 21 is switched to a driving state. To calculate the arithmetic mean, the absolute values of the measured values are determined and used.

[0108] In a manner analogous to the example described above, it is also possible that the computing unit 34 calculates a statistical measure of the spread the variance for the values in the non-powered state. If the statistical measure of the spread (the variance) lies within a tolerance interval, the motor 21 is switched to the non-driving state. If the statistical measure of the spread (the variance) lies outside a tolerance interval, the motor 21 is switched to the driving state by the computing unit 34.

[0109] In a fourth exemplary embodiment, which is likewise not shown, a second tolerance interval around the reference value can be defined, for example ±15 Newtons. The second tolerance interval thus lies inside the first tolerance interval. If at least a second predetermined number of measured values in the non-powered state do not lie outside the second tolerance interval, in particular if all the measured values in the non-powered state lie within the second tolerance interval, then the brake is actively actuated (in addition to switching the motor 21 to a non-driving state).

[0110] FIG. 5 shows a flow diagram 50 which illustrates the method for determining whether an operator is interacting with a stroller frame. First, in a determination step 52, sensor data are received and processed. In the determination step, a reference value 53 is calculated, which can indicate for example a mean value of the sensor data 51.

[0111] In the subsequent comparison step 55, a current measured value 54 is received and is compared with the reference value. In the interval determination step 57, a tolerance interval is set around the reference value. For this, the value of the reference value can be taken into account. This means that a large tolerance interval will be determined in the case of a large reference value and a small tolerance interval will be determined in the case of a small reference value.

[0112] In addition, the gap 58 between the current measured value 54 and the interval limits is determined. In the checking step 59, it is checked whether the current measured value 54 or at least one of the other measured values of the considered time interval lies outside the tolerance interval (in general: whether in total at least a first predetermined number of measured values in the considered time interval lie outside the tolerance interval). If the current measured value 54 and all the other measured values in the considered time interval lie within the tolerance interval (in general: if fewer than a first predetermined number of measured values in the considered time interval lie outside the tolerance interval), then a motor of the stroller is switched to a non-driving state in the braking step 61. In one exemplary embodiment, the motor is switched to a braking state so that the stroller 1 stops. If it is ascertained that the current measured value 54 or at least one of the other measured values in the considered time interval lies outside the tolerance interval (in general: if in total at least a first predetermined number of measured values in the considered time interval lie outside the tolerance interval), then a motor is switched to a driving state so that the stroller can be driven entirely or in an assisted fashion by the motor.

[0113] The invention also explicitly encompasses the scenario where the computing unit is embodied by a server communicatively connected to the stroller frame or stroller. For example, only the sensor data can be transmitted to the server via a communication device, wherein all the calculation steps are carried out on the server and control commands to the stroller and/or the communication device are sent back.

LIST OF REFERENCE SIGNS

[0114] 1 stroller [0115] 2 wheel [0116] 3 wheel mount [0117] 10 stroller frame [0118] 11 framework [0119] 12 pusher portion [0120] 13, 13′ side struts [0121] 14, 14′ connecting element [0122] 15 adjusting device [0123] 16 transverse strut [0124] 17 rear wheel suspension [0125] 18 front wheel suspension [0126] 19 front wheel strut [0127] 20 parking brake [0128] 21 motor [0129] 22 braking device [0130] 23 accumulator [0131] 24 rear wheel axle [0132] 25 retaining devices [0133] 26 pusher receiving devices [0134] 31 first sensor region [0135] 32, 32′ second sensor region [0136] 33, 33′ third sensor region [0137] 34 computing unit [0138] 30, 30′, 30″ force sensor [0139] 30′″ torque sensor [0140] 40 force diagram [0141] 41 sensor data [0142] 42 subset of the sensor data [0143] 43, 43′ measured value [0144] 44 tolerance interval [0145] 50 flow diagram [0146] 51 sensor data [0147] 52 determination step [0148] 53 reference value [0149] 54 current measured value [0150] 55 comparison step [0151] 56 deviation [0152] 57 interval determination step [0153] 58 gap to interval limit [0154] 59 checking step [0155] 60 driving step [0156] 61 braking step [0157] F1 mean value [0158] F force axis [0159] T[s] time axis [0160] t.sub.0 first measurement time [0161] t.sub.1 current measurement time [0162] S1 non-driving state/braking state [0163] S2 driving state