Toy vehicle having a yaw rate sensor
Patent Information
- Application Number
- EP2023721321
- Authority / Receiving Office
- EP · EP
- Patent Type
- Applications
- Current Assignee / Owner
- Priority Date
- 2022-04-19
- Filing Date
- 2023-04-19
- Publication Date
- 2025-02-26
- Estimated Expiration
- 2043-04-19
Smart Images
Figure 1.1
Abstract
Description
[0001] Description
[0002] Toy vehicle with gyroscope
[0003] The invention relates to a toy vehicle according to the preamble of claim 1 and to a toy vehicle system comprising such a toy vehicle.
[0004] In toy vehicles, particularly remote-controlled model cars, one technical task is to convert a steering signal into a steering movement of the steerable wheels responsible for steering the vehicle. Proportional steering is achieved by a steering unit of the toy vehicle in a conventional design. A steering drive acts on the steerable wheels via a suitable mechanism, while the achieved steering angle is determined and fed back by a position measurement. A so-called servo is commonly used here, which acts on the steering mechanism via a pivoting servo arm and a connected rod. For this position measurement, the servo contains a potentiometer, via which the angular position of the servo arm and thus indirectly also the steering position of the wheels is determined and fed back.This allows a deflection of the servo arm proportional to the control signal and a steering movement of the wheels that is functionally dependent on this.
[0005] In addition, it is known to connect a so-called gyro in addition to the servo system with steering drive and position measurement. These historically based terms, referring to mechanical gyros, today generally refer to an electronic yaw rate sensor, which can detect a change in direction relative to a reference direction. Such yaw rate sensors are connected between the receiver unit that outputs the control signal and the servo in order to stabilize the direction or even maintain the specified direction of travel in conjunction with a suitable control loop.
[0006] It has been shown that with the progressive miniaturization of such toy vehicles, their steering becomes increasingly nervous, with mechanical deficiencies such as steering play or the like becoming more pronounced. Achieving manageable steering becomes more difficult as the vehicle becomes smaller. In particular, the direct or indirect determination of the steering angle, for example via the aforementioned servo potentiometer, requires virtually no installation space in small toy vehicles. In addition, part of the power of the steering drive must be used to overcome mechanical friction in determining the steering angle, which necessitates correspondingly powerful dimensions of the steering drive. Added to this is a considerable susceptibility to errors and the corresponding costs. These problems are further exacerbated if a yaw rate sensor is also to be used.
[0007] The invention is based on the object of simplifying a generic toy vehicle in such a way that uncomplicated, controllable steering is possible, especially in small sizes.
[0008] This object is achieved by a toy vehicle having the features of claim 1.
[0009] The invention is further based on the object of providing a toy vehicle system in which the aforementioned toy vehicle can be moved along a predetermined lane.
[0010] This object is achieved by a toy vehicle system having the features of claim 11. The invention is based on the idea of completely dispensing with direct or indirect determination of the steering angle and implementing the steering via a control loop with a yaw rate sensor, not as a supplement to the steering angle determination, but instead. A yaw rate sensor for determining the yaw rate of the toy vehicle about its vertical axis, a steering drive, and a control unit together form a control loop for setting the said yaw rate of the toy vehicle to a predetermined target value. In this highly effective control loop, the size of the steering angle and its determination are not important at all. Rather, the control process running in the control unit only needs to influence the steering drive in such a way that the desired or predetermined yaw rate of the vehicle is established. The current yaw rate is determined by the yaw rate sensor.The control loop acts on the steering in such a way that the actually determined vehicle rotation rate is brought into line with the target value or at least sufficiently close to it.
[0011] The process of starting off is one example. The toy vehicle is parked on its track, whereby the current steering angle is irrelevant. This can initially have any value and, depending on the randomly existing steering angle position, leads to more or less pronounced cornering when setting off. The yaw rate of the toy vehicle around its vertical axis that accompanies cornering occurs immediately after setting off and can also be immediately detected by the yaw rate sensor. The aforementioned control loop now influences the steering at a high control speed in such a way that the target value of the vehicle's yaw rate (= 0 when driving straight ahead, 0 when cornering) is established after a very short control time.
[0012] By eliminating the need for steering position determination, the effort, installation space, and especially the mechanical resistance of a potentiometer and its actuation mechanism are eliminated. Accordingly, a small and low-geared steering drive can suffice. Particularly due to the latter aspect of the low gear ratio, a very responsive control loop can be realized, as required for the adjustment of small, fast-reacting systems. Control deviations can be reduced to the imperceptible level. Steering play or other deficiencies can be easily corrected, so that a simple and cost-effective mechanical design is sufficient. Overall, only a small installation space is required, which fulfills another prerequisite for the realization of small toy vehicles. The low gear ratio of the steering operation also has the advantage of mechanical insensitivity.Despite its delicate design, the risk of damage to the steering gear is low.
[0013] Various options are possible for generating the desired yaw rate. In a preferred embodiment of the invention, the control unit of the toy vehicle includes a receiver for control signals from a remote control, wherein the control unit is designed to derive a desired value for the vehicle's yaw rate from the control signals received in the receiver. Thus, when the receiver receives the control signal from the remote control to drive straight ahead or around a curve, the control unit converts this control signal into a corresponding desired value for the yaw rate. The control loop described above then regulates the actual yaw rate of the toy vehicle to the specified desired value, so that the toy vehicle follows the control signals from the remote control.
[0014] Alternatively, or in combination with this, the control unit can contain at least one sensor for detecting a predetermined driving lane, in which case the control unit is then designed to derive the target value for the rotation rate from the sensor signals determined by the sensor. In this context, the control unit is advantageously designed to derive the target value for the rotation rate from the sensor signals determined by the sensor in such a way that the toy vehicle follows the driving lane. This can be used, for example, to implement training operations in which the vehicle initially follows a predetermined driving lane automatically. Additional control signals from a remote control can then be modulated onto this. The user is thus able to change the driving path, find an ideal line, or familiarize themselves with the controls in another way, without the vehicle running the risk of constantly going off track.
[0015] In addition, or in addition, it may be expedient for the control unit to be designed to derive certain driving events, in particular braking, acceleration, and / or intervention in the yaw rate, from the sensor signals detected by the sensor. In a simple form, this could, for example, involve detecting certain positions in the lane leading to certain control events. Reaching the edge of the road, for example, could lead to deceleration, the simulation of an evasive steering maneuver, or a steered skid.
[0016] For the technical implementation of detecting a given lane, an IR (infrared) sensor with an IR transmitter and an IR receiver has proven to be suitable. In the corresponding toy vehicle system, the lane is provided with an IR-sensitive orientation pattern. Because infrared detection occurs outside the light spectrum perceptible to the human eye, the technical function of lane detection can be decoupled and separated from the visual appearance of the lane. This makes it possible, in particular, to provide a lane resembling a road or racetrack, within which IR-sensitive orientation patterns are discreetly hidden. In an advantageous variant, the IR-sensitive orientation pattern is covered by an IR-permeable and visually opaque cover layer.The latter provides complete design freedom for the optical appearance, which is completely separate from lane detection. For lane detection, the surface layer is illuminated in the IR range in a way that is imperceptible to the eye. This enables scanning of the underlying orientation pattern without impairing the appearance perceived by the eye. In an advantageous embodiment, the IR-sensitive orientation pattern comprises a pattern of alternating light and dark triangular sections extending across the lane. When driving over such triangular sections, the sensor detects a sequence of light and dark areas, with the relative ratio of light to dark providing simple information about the vehicle's exact position laterally on the road. A change in the relative ratio can also be used to derive a direction of movement relative to the longitudinal direction of the road.
[0017] In a further advantageous embodiment, the IR-sensitive orientation pattern comprises a pattern of alternating light and dark lines extending across the lane. Such patterns can, for example, be applied to the front ends of a road segment. The vehicle's sensor then uses a specific line pattern to recognize, for example, the type of road segment that follows, i.e., whether it is a straight line, a curved section, or the like. Alternatively or additionally, such a line pattern can also mark a specific location associated with an event. It can therefore be a start / finish line or the like, which is recognized by the sensor in the manner described above, and crossing which, under certain circumstances, triggers predetermined events such as timekeeping, the termination of a race after a certain number of laps has been reached, or the like.
[0018] In a preferred embodiment, the toy vehicle is a replica of a car with at least two steerable wheels and at least two non-steerable wheels. The vehicle stands or drives independently on its wheels and can be controlled with minimal technical effort in such a way that a realistic driving experience is created.
[0019] In an advantageous variant, the toy vehicle is a replica of a motorcycle with one steerable wheel and one non-steerable wheel. This presents additional technical challenges regarding the assumption of a certain lean angle when cornering, but also opens up additional possibilities for designing ferry operations.
[0020] In principle, it is conceivable that such a motorcycle replica could also regulate the lean angle assumed during operation with the aid of suitable sensors. This requires, however, that the lean angle is adapted to the centrifugal force prevailing when cornering. However, a reduced-scale replica of a motorcycle and the route to be traveled, combined with suitable cornering speeds, would lead to unrealistic-looking lean angles that would impair the visual appearance during operation. Therefore, the toy vehicle designed as a replica of a motorcycle preferably has a controlled support device for specifying an inclination angle of the vertical axis relative to a surface normal of the lane to be traveled. The support device can be easily concealed so that it is barely noticeable to the observer.It allows the setting of a vehicle inclination to simulate a scaled-down ferry operation with a realistic overall impression, although the actual centrifugal forces would require a different, usually lower, inclination.
[0021] The swivel angle of such a support device can be adjusted, for example, using a servo of a known design with a potentiometer. In a preferred development, however, the control of the support device is carried out according to the same principle as for the steering drive described above: The support device, which is subject to the effect of the swivel drive, is pivotally mounted on the chassis of the toy vehicle with a variable swivel angle. The steering unit comprises a yaw rate sensor for determining the yaw rate of the toy vehicle about its longitudinal axis and is free of a sensor for determining the swivel angle. The swivel drive, the control unit, and the yaw rate sensor together form a control loop for setting the yaw rate to a predetermined target value. This results in the same advantages as those described above in connection with the control of the steering.
[0022] It should be expressly noted at this point that, within the scope of the invention, the control of the yaw rate described here can be applied either to the steering (yaw rate control of the toy vehicle around its vertical axis) alone, to the vehicle's lean angle (yaw rate control of the toy vehicle around its longitudinal axis) alone, or to a combination thereof. This includes the option of combining a steering control according to the invention with a servo-driven lean angle adjustment or a servo-driven steering system with a lean angle control according to the invention.
[0023] An embodiment of the invention is described in more detail below with reference to the drawings. They show:
[0024] Fig. 1 shows a perspective schematic representation of a toy vehicle according to the state of the art with steering drive, control unit and potentiometer for indirect detection of the steering angle,
[0025] Fig. 2 shows a perspective schematic representation of a first modification of the toy vehicle according to the invention as a replica of a car with a rotation rate sensor instead of the potentiometer,
[0026] Fig. 3 shows a variant of the toy vehicle according to Fig. 2 with a toothed segment steering instead of a rack and pinion steering,
[0027] Fig. 4 shows a schematic representation of a toy vehicle system according to the invention with a toy vehicle according to Fig. 2 or 3, with an IR-sensitive lane and with a smartphone as a remote control, Fig. 5 shows a schematic side view of an alternative embodiment of the toy vehicle as a replica of a motorcycle with a support device for adjusting an inclination angle of the vehicle's vertical axis, and
[0028] Fig. 6 shows a front view of the toy vehicle according to Fig. 5 in curve travel and with the angle of inclination adjusted by means of the support device.
[0029] Fig. 1 shows a schematic perspective view of a toy vehicle 1' according to the prior art, wherein the toy vehicle 1' is a replica of a car. The body, drive, rear wheel suspension, or the like are not shown here for clarity. The toy vehicle 1' has a vehicle-fixed longitudinal axis x and a vehicle-fixed vertical axis z. In normal ferry operation, the toy vehicle 1' moves in the direction of its longitudinal axis x and also performs rotational movements around the vertical axis z at a rotation rate co z as a result of a steering movement.
[0030] The toy vehicle 1' has two front, steerable wheels 2 and two rear, driven, non-steerable wheels 3 located on a rigid axle. The front wheels 2 are steerably mounted on a chassis 16 of the toy vehicle 1' by means of steering knuckles, so that they can be adjusted to a desired steering angle a about vertically extending steering axes 27. The selection of the steering angle a leads to a corresponding rotation rate co when the toy vehicle 1 travels in the direction of its longitudinal axis x, depending on the current speed. z around the vertical axis z, where the rotation rate co zis zero when driving straight ahead and deviates from zero when cornering. The toy vehicle 1' comprises a steering drive 4 acting on the steered wheels 2, which in turn is acted upon by a control unit 5. The control unit 5 comprises a receiver 7, only schematically indicated, for the control signals from a transmitter, not shown. These control signals are converted in the control unit 5 for controlled actuation of the steering drive 4. The steering drive 4 comprises an electric steering motor 20, which adjusts the steering angle a of the front wheels 2 via a steering gear 17. For this purpose, the steering gear 17 comprises a pinion 18, which engages in a rack 19 connected to the steering knuckles of the front wheels 2. A lateral thrust movement of the rack 19 caused thereby aligns the front wheels 2 at a desired steering angle a.
[0031] To provide feedback on the aforementioned steering movement, the steering unit shown here is equipped with a sensor for determining the steering angle α, according to the state of the art. Based on the principle of a servo drive, the sensor is integrated into the steering gear 17 and, in its design shown here as a potentiometer 15, is coupled to the steering movement of the wheels 2 via its own gear set. In the sense of indirect steering angle detection, the achieved steering angle α can be determined from the output value of the potentiometer 15, the known reduction ratio of the steering gear 17, and the overall known steering kinematics. The achieved steering angle α is fed back to the control unit 5 in the form of the output value from the potentiometer 15, thereby forming a proportional control.
[0032] Fig. 2 shows a perspective view of a toy vehicle 1 as a modification according to the invention of the toy vehicle 1' according to Fig. 1. Unless expressly stated otherwise, the same features, properties and effects apply, with the same reference numerals being used for the same features.
[0033] The effect of the steering motor 20 by means of the steering gear 17 on the adjustment of the steering angle a of the front wheels 2 is as described above. However, a potentiometer 15 (Fig. 1) or another sensor for determining the steering angle a and its feedback to the control unit 5 is missing. The steering angle a actually present or set during operation is not known in the control unit 5 and is also not required according to the invention. Rather, the steering unit of the toy vehicle 1 according to the invention comprises, instead of the aforementioned steering angle sensor, a rotation rate sensor 6 for determining the currently existing rotation rate co. zof the toy vehicle 1 around its vertical axis z. The yaw rate sensor 6 is connected together with the steering drive 4 and the control unit 5 to form a control circuit by means of which the yaw rate co z of the toy vehicle 1 is set to a predetermined target value. For this purpose, a comparison of the actual rotation rate co determined by the rotation rate sensor 6 is carried out in the control unit 5. zwith the specified setpoint. The control deviation determined from this comparison is converted in the control unit 5 into a corresponding control of the steering drive 4, which leads to a reduction or elimination of the control deviation by adjusting the steering angle a of the steerable wheels 2. In the present case, a P controller (proportional controller) is used for this purpose, which allows a certain and, in practice, tolerable control deviation. For more stringent control requirements, however, a different controller, for example a PID controller (proportional-integral-derivative controller) or an even more complex control system, can be selected.
[0034] In the embodiment according to Fig. 2, the case of straight-ahead travel is shown, with the associated operating method according to the invention being described below. The steerable wheels 2 have a steering angle a of 0°, so that they are aligned substantially parallel to the longitudinal axis x. The associated rotation rate co z is equal to 0. If the receiver 7 receives a control signal for straight-ahead travel from a remote control 8 shown in Fig. 4, the setpoint for the rotation rate co z to 0, which corresponds to the desired straight-ahead travel. If the toy vehicle actually travels straight, there is no control deviation, and the aforementioned control loop does not intervene. However, if the vehicle is deflected with its longitudinal axis x from the underlying direction of travel due to, for example, an uneven ground or any other disturbance, this occurs with a rotation rate co z0, which is detected by the yaw rate sensor 6 and which represents a control deviation. According to the control deviation, the control loop adjusts the steering (change of the unknown steering angle a) until straight-ahead travel with the corresponding actual yaw rate co z = 0 as the setpoint is reached. In the case of pure P-control, this can result in a deviation of the alignment of the longitudinal axis x from the previous alignment, which is usually sufficient to stabilize the vehicle. For more stringent control requirements, where, for example, a return to the original alignment of the longitudinal axis x is important (heading hold), the use of PID control is advisable. In a similar way, a controlled cornering with a rotation rate cn z 0 can be realized as the target value.
[0035] In any case, a potentiometer 15 (Fig. 1) along with its associated drive or any other sensor for determining the steering angle α was completely omitted. The actual size of the current steering angle α is irrelevant for the functioning of the control circuit according to the invention. Furthermore, the yaw rate sensor 6 is an electronic component without any mechanically moving parts and requires minimal installation space overall. It is shown schematically here outside of the control unit 5 for easy identification. In practice, however, it is integrated into the control unit 5 without taking up additional installation space. The arrangement according to the invention shown is overall small-volume, mechanically insensitive, cost-effective, and simple, and is therefore particularly suitable for micro-sized toy vehicles for operation, for example, in the living room or on a tabletop.
[0036] Fig. 3 shows a variant of the toy vehicle 1 according to Fig. 2 with a slightly modified steering mechanism 17. The steering knuckles of the steerable front wheels 2 are not connected to a rack 19 (Fig. 2), but rather to a circular segment-shaped toothed segment 22, in whose toothing a common pinion 21 with a vertical axis of rotation engages, located centrally therebetween. In the remaining features and reference numerals, the exemplary embodiment according to Fig. 3 corresponds to that according to Fig. 2. By way of example, Fig. 3 shows the case of a steering deflection of the front wheels 2 with a steering angle a 0 when starting off, whereby the associated operating method according to the invention is also described below. As soon as the vehicle is set in motion, the steering deflection leads to cornering of the toy vehicle 1, which in turn, depending on the current speed, has a corresponding rotation rate co zaround the vertical axis z. When starting from a standstill, the initial steering angle a is not important. The toy vehicle 1 can be parked on its roadway with any steering angle a, for example, as shown in Fig. 3. As long as it is not moving, the actual yaw rate coz = 0. However, as soon as the vehicle is set in motion via its existing, although not shown, drive, the deflected wheels 2 lead to an initial cornering with a corresponding yaw rate coz deviating from zero, which is immediately detected by the yaw rate sensor 6 and compared in the control unit 5 with the predetermined target value. If this target value is equal to 0 (desired straight-ahead travel), the control circuit according to the invention adjusts the steering until straight-ahead travel with a yaw rate co z= 0 is detected by the yaw rate sensor 6 and fed into the control unit 5. Only minimal distances are required for this. The process of adjusting to straight-ahead travel from the initial position of the deflected wheels 2 is so fast that it is practically unnoticeable by the user. The same applies, of course, to adjusting to an intended cornering, where the target value of the yaw rate co z deviates from 0.
[0037] Fig. 4 shows a perspective overview of a toy vehicle system according to the invention, which comprises a toy vehicle 1 according to Fig. 2 or 3, a roadway with a lane 12 and a remote control 8. In addition to the equipment shown in Figs. 2 and 3, the toy vehicle 1 is also provided with at least one sensor 9 for detecting the predetermined lane 12. This sensor is an IR sensor with an IR transmitter 10 and an IR receiver 11. A straight road segment of the lane 12 is shown here as an example. However, it can also be a curved segment, a pit lane segment or the like, whereby any desired lanes can then be assembled from such segments. However, a one-piece lane 12 can also be provided, already formed into a complete track. The lane 12 is provided with an IR-sensitive orientation pattern 13 corresponding to the IR sensor.Various shapes are possible for the design of the orientation pattern 13. In the preferred embodiment shown, it comprises a pattern of triangles extending transversely across the lane 12, alternating light and dark (in the IR range). Triangular segments of these triangles extend across the lane 12, while the apices of the triangles, which are irrelevant for orientation purposes, have been omitted for simplicity. In more precise definition, it is therefore a pattern of triangular segments 23, or trapezoids, extending transversely across the lane 12, alternating light and dark. Furthermore, the IR-sensitive orientation pattern 13 comprises a pattern of lines 24 extending transversely across the lane 12, alternating light and dark (in the IR range). In the present case, such a pattern of light and dark lines 24 is located at each end of the lane segment.Applying a pattern of light and dark lines can also be useful elsewhere.
[0038] As the toy vehicle 1 travels along the lane 12, according to the invention and according to an operating method according to the invention, an IR beam emitted by the IR transmitter 10 strikes the orientation pattern 13, is reflected there, and finally received by the IR receiver 11. The intensity of the received IR beam depends on whether the emitted IR beam strikes a light or a dark section of the IR-sensitive orientation pattern 13. As the toy vehicle 1 travels along the lane 12, the IR receiver 11 receives alternating weak and strong reflected signals. When the pattern of triangular sections 23 is detected, the signal sequence of weak and strong signals changes with a change in the lateral positioning of the toy vehicle 1 relative to the lane 12. Using a suitable evaluation algorithm, it can be determined how far the toy vehicle 1 is to the left or right on the lane 12.In addition, the orientation of the vehicle's longitudinal axis x (Fig. 2, 3) relative to the longitudinal direction of the lane 12 can be determined.
[0039] In addition, specific information can be encoded in the pattern of light and dark lines 24, which is detected by the IR sensor when the vehicle is driven over and then decoded, for example, in the control unit 5. For example, the type of road segment (straight, tight curve, wide curve, or the like) can be encoded in the pattern of light and dark lines 24. When entering such a road segment, the system uses the IR sensor to detect the type of the following road segment, so that further operation can be prepared, for example by adjusting the speed. Of course, other information can also be encoded in the pattern of light and dark lines 24, such as the presence of a start and finish line. This information is recorded and decoded in the same way, so that corresponding events (time measurement, lap counting, etc.) can be triggered.
[0040] Particularly in the context of the toy vehicle system shown, the aforementioned sensor 9 is a functional part of the control unit 5 (Figs. 2, 3), wherein the control unit 5 is designed to derive the setpoint value for the rotation rate coz from the control signals determined by the sensor 9. On the one hand, the setpoint values for the rotation rate co z be derived and determined in such a way that the toy vehicle 1 automatically follows the lane 12. Alternatively or additionally, the control unit 5 can be designed to determine certain driving events, in particular braking, acceleration and / or intervention in the rotation rate co, from the sensor signals determined by the sensor 9. z For example, the vehicle can be braked when reaching the edge of the lane and accelerated when reaching the center of the lane. Furthermore, evasive or skidding movements can be controlled by changing the yaw rate. zbe simulated. In particular, the control unit derives the target value for the yaw rate coz as a function of both the sensor signals determined by sensor 9 and the control signals generated by remote control 8 and received by receiver 7. This enables, for example, a driving simulation in which the user can freely steer the toy vehicle 1 along lane 12, provided certain conditions are met. However, if the user steers the toy vehicle 1 too close to the edge or into a specially marked zone, this is detected by sensor 9. As a result, predetermined driving events, as mentioned above, can be triggered, which intervene in the user's control signals. This intervention can be an overlay (changed steering or braking effect).It's also possible to completely override the control signals generated by the user, for example, to force the toy vehicle to stop or move to the edge of the road. Of course, a multiplayer mode is also possible, with or without corresponding, coordinated driving events.
[0041] Overall, this enables a realistic, small-scale ferry operation along a predefined lane 12 with a realistic appearance. The driving behavior of the toy vehicle 1 can be adjusted to almost any level of difficulty and adapted to the user's skill level. This can be set to varying degrees of difficulty, from fully autonomous operation, in which the toy vehicle 1 automatically follows lane 12, to freely controlled, electronically uninfluenced ferry operation.
[0042] Since the essential property of lane 12 lies in its orientation pattern 13, it can be manufactured cost-effectively from simple materials such as cardboard or the like. Almost any desired lane can be formed from standardized segments of this pattern and closed into a ring. Optionally, the IR-sensitive orientation pattern 13 is covered by an IR-transparent, yet visually opaque, cover layer 14, creating the visual appearance of an asphalt lane with shoulders and median strips, a gravel track, or any other simulated roadway. The underlying orientation pattern 13 is thus concealed and remains invisible to the human eye, but is still accessible to the IR sensor 9.
[0043] A classic remote control known from vehicle model construction can be used as the remote control 8. Preferably, as shown in Fig. 4, the remote control 8 is a smartphone with an app installed on it that generates the control signals for the toy vehicle 1. The radio connection between the remote control 8 and the toy vehicle 1 is preferably via Bluetooth. However, a Wi-Fi connection or another form of radio connection may also be suitable. The app installed on the smartphone can be simple, purely a control app, or complex, with a sophisticated driving simulation. In particular, a multiplayer mode via an internet connection is possible.In this case, several players, even those physically separated from each other, can build the same track from lane segments and drive it simultaneously and against each other in competitive mode, without the need for a physical encounter. Collisions, overtaking maneuvers, and the like can be simulated using the methods described above.
[0044] Another aspect is that the toy vehicle 1 can drive the entire track once, either independently or under the control of the user, and can thereby detect it using the IR sensor 9. In this way, the course of the laid-out lane 12 can be detected and fed into the simulation before the actual training or competition run begins.
[0045] The invention is described above using an example in which the toy vehicle
[0046] 1 is a replica of a car with at least two, here exactly two steerable wheels 2 and with at least two, here exactly two non-steerable wheels 3. For the sake of simplicity, the yaw rate sensor 6 is only a single-axis yaw rate sensor for detecting the yaw rate co z around the vertical axis z.
[0047] In an alternative embodiment of the invention, the toy vehicle 1 according to the illustration in Figs. 5, 6 is a replica of a motorcycle with only one steerable wheel 2 and with only one non-steerable wheel 3. The wheel 2, which is mounted on the chassis of the toy vehicle 1 with a variable steering angle a about a steering axis 27, is in the same way as in the embodiment according to Figs. 1 to 4 under the action of the steering drive 4, which enables the regulation of the rotation rate co described in detail above. z around the vertical axis z by means of steering drive 4, control unit 5 and yaw rate sensor 6.
[0048] The yaw rate sensor 6, like the control unit 5, is designed and able to measure, in addition to the yaw rate, z around the vertical axis z also the rotation rate co x around the longitudinal axis x (Fig. 6) and rotation rate co y to detect the transverse axis y. This is the currently standardized design of commercially available yaw rate sensors 6, which is preferably used not only here in the simulation of a motorcycle, but also in practice in the simulation of a car according to Figs. 1 to 4.
[0049] In the front view according to Fig. 5, it can be seen that when cornering the toy vehicle 1, which is modeled as a motorcycle, its vertical axis z is inclined relative to a surface normal z' of the lane 12 to be traveled by an oblique angle y. Together with the toy vehicle 1, its yaw rate sensor 6 is also inclined by this oblique angle y. Cornering on the lane 12 leads to a yaw rate co z- of the toy vehicle around the surface normal z', i.e. around an axis that is perpendicular to the surface of the lane 12. The yaw rate sensor, which is inclined by the oblique angle y, records a resulting yaw rate co z around the vertical axis z and a resulting rotation rate co y around the transverse axis y, from which the rotation rate coz around the surface normal z' is readily derived, so that controlled cornering and straight-ahead travel, as in the embodiment shown in Figs. 1 to 4, is possible and is carried out in operation. When traveling straight ahead, the skew angle y is zero, meaning that the vertical axis z is upright and parallel to the surface normal z'.
[0050] 5 and 6 together, it can be seen that the toy vehicle 1, designed as a replica of a motorcycle, has a controlled support device 25 for specifying the oblique angle y described above. In the exemplary embodiment shown, the support device is a pair of laterally projecting arms attached to the underside of the toy vehicle 1. At least one of these arms, here both arms, rests with their end regions on the track 12 during operation. For this purpose, small support rollers are attached to their ends, which roll along the track 12. Instead of the support rollers, sliding skids or the like can also be expedient. The arms of the support device 25 are pivotally mounted on the chassis of the toy vehicle 1 at a variable pivot angle θ, with the associated pivot axis running parallel to the longitudinal axis x of the toy vehicle 1.A pivot drive 26 acts on the arms of the support device 25 to adjust the pivot angle 6. It may also be expedient for each arm to have its own pivot drive 26. The respectively set pivot angle 6 specifies the inclination angle y of the vertical axis z of the toy vehicle 1 relative to the surface normal z'.
[0051] The swivel drive 26 can be a servo with a potentiometer in a conventional design. In the preferred embodiment shown, the swivel drive 26 is part of the steering unit already described above, whereby the steering unit is free of a sensor for determining the swivel angle θ. Thus, in connection with the adjustment of the skew angle γ, the steering unit also manages without a potentiometer of a servo or the like. Rather, analogous to the steering of wheel 2 about its steering axis 27, the swivel drive 26, the control unit 5, and the yaw rate sensor 6 together form a control circuit for adjusting the yaw rate θ.x to a predetermined setpoint: If, for example, the toy vehicle is transferred from a straight line to a curve, then for a realistic appearance it must be brought from an upright position to an inclined position with an inclination angle y 0. For this purpose, in the method according to the invention in the control unit a corresponding setpoint of the rotation rate co x generated, as a result of which a changed swivel angle 6 of the support device 25 is approached. As a result, the inclination angle y changes with a rotation rate co x until the skew angle y has reached its desired value. As soon as this has happened, the setpoint value of the yaw rate co x reduced accordingly, and the desired y-bevel angle achieved is maintained. Adjustments to different y-bevel angles work in the same way, as does the uprighting of the toy vehicle after completing the turn.
Claims
Claims: Toy vehicle (1) with wheels (2, 3) and with a steering unit, wherein the steering unit comprises a steering drive (4) acting on at least one of the wheels (2) and a control unit (5) acting on the steering drive (4), and wherein the at least one wheel (2) under the influence of the steering drive (4) is steerably mounted on a chassis of the toy vehicle (1) with a variable steering angle (a), characterized in that the steering unit includes a yaw rate sensor (6) for determining a yaw rate (co z ) of the toy vehicle (1) encompasses around its vertical axis (z) and is free of a sensor for determining the steering angle (a), and that the steering drive (4), the control unit (5) and the yaw rate sensor (6) together form a control loop for adjusting the yaw rate (co z) to form a predetermined target value. Toy vehicle (1) according to claim 1, characterized in that the control unit (5) includes a receiver (7) for control signals from a remote control (8), and that the control unit (5) is designed to derive the target value for the rotation rate (co) from the control signals received in the receiver (6). z ) to derive. Toy vehicle (1) according to claim 1 or 2, characterized in that the control unit (5) includes at least one sensor (9) for detecting a predetermined driving lane (12), and that the control unit (5) is designed to derive the target value for the rotation rate (co) from the sensor signals determined by the sensor (9). z ) to derive. Toy vehicle (1) according to claim 3, characterized in that the control unit (5) is designed to derive the target value for the rotation rate (co) from the sensor signals determined by the sensor (9). z) such that the toy vehicle (1) follows the lane (12). Toy vehicle (1) according to claim 3 or 4, characterized in that the control unit (5) is designed to derive certain driving events, in particular braking, acceleration, and / or intervention in the rotation rate (co) from the sensor signals determined by the sensor (9). z) to derive. Play vehicle (1) according to one of claims 3 to 5, characterized in that the sensor (9) for detecting the predetermined lane (12) is an IR sensor with an IR transmitter (10) and with an IR receiver (11). Play vehicle (1) according to one of claims 1 to 6, characterized in that the play vehicle (1) is a replica of a car with at least two steerable wheels (2) and with at least two non-steerable wheels (3). Play vehicle (1) according to one of claims 1 to 6, characterized in that the play vehicle (1) is a replica of a motorcycle with one steerable wheel (2) and with one non-steerable wheel (3). Play vehicle (1) according to claim 8, characterized in that the play vehicle (1) designed as a replica of a motorcycle has a controlled support device (25) for specifying a oblique angle (y) of the vertical axis (z) relative to a surface normal (z 1) of a lane (12) to be traveled. Toy vehicle (1) according to claim 9, characterized in that the steering unit comprises a pivot drive (26) acting on the support device (25), wherein the support device (25) under the action of the pivot drive (26) is pivotably mounted on a chassis of the toy vehicle (1) with a variable pivot angle (6), wherein the steering unit includes a yaw rate sensor (6) for determining a yaw rate (co x ) of the toy vehicle (1) encompasses around its longitudinal axis (x) and is free of a sensor for determining the swivel angle (6), and that the swivel drive (26), the control unit (5) and the yaw rate sensor (6) together form a control loop for adjusting the yaw rate (co x) to form a predetermined target value. Play vehicle system, comprising a play vehicle (1) according to any one of claims 1 to 10, and further comprising a driving lane (12) for the play vehicle (1), wherein the control unit (5) comprises at least one sensor (9) for detecting the predetermined driving lane (12), play vehicle system according to claim 11, characterized in that the sensor (9) for detecting the predetermined driving lane (12) is an IR sensor, and that the driving lane (12) is provided with an IR-sensitive orientation pattern (13). Play vehicle system according to claim 12, characterized in that the IR-sensitive orientation pattern (13) comprises a pattern of alternating light and dark triangular segments (23) extending transversely across the driving lane (12). A play vehicle system according to claim 12, characterized in that the IR-sensitive orientation pattern (13) comprises a pattern of alternating light and dark lines (24) extending transversely across the driving lane (12). A play vehicle system according to any one of claims 12 to 14, characterized in that the IR-sensitive orientation pattern (13) is covered by an IR-transparent and visually opaque cover layer (14).