Pseudo-obstacle transporting device

Abstract

Provided is a pseudo-obstacle transporting device that travels with a pseudo-obstacle loaded thereon and comprises: a steering wheel for manipulating travel direction; a housing that covers the steering wheel; and a steering power unit that is connected to the housing and changes the travel direction by applying an external force to the steering wheel. The steering wheel is configured to be grounded on an extension of the steering shaft thereof. The steering wheel has the steering shaft accommodated inside a wheel, and is provided with a first connection mechanism for connecting the steering shaft and the housing and a second connection mechanism for connecting the steering shaft and the steering power unit. The second connection mechanism is connected to the steering shaft positioned inside the wheel from the side opposite the first connection mechanism across the steering shaft.

Description

Pseudo obstacle transport device

[0001] The present invention relates to a pseudo obstacle transporting device used in automobile performance testing.

[0002] In order to objectively evaluate a vehicle's obstacle recognition and avoidance performance, a performance test is conducted by simulating specific collision conditions to evaluate the degree of collision avoidance and damage reduction. This performance test is conducted using a vehicle to be evaluated and a simulated obstacle transporter (hereinafter abbreviated as "transporter") (see, for example, Patent Document 1). The transporter runs while carrying simulated obstacles (e.g., dummies simulating various obstacles such as people and bicycles) used in vehicle performance tests, reproducing the movements of various obstacles. By conducting a highly reproducible performance test using the transporter, the vehicle's collision safety can be accurately evaluated.

[0003] Special table 2019-520163 publication

[0004] In automobile performance tests, when a vehicle collides with a simulated obstacle, the transport device may be run over by the wheels of the vehicle. In this case, the transport device is dragged by the vehicle, and this dragging applies a moment around the steering axis to the steering wheel as an external force, which may damage the power unit that drives the steering wheel.

[0005] An object of the present invention is to provide a pseudo obstacle transporting device that can reduce the external force applied to the steering wheel when it interferes with an automobile, thereby suppressing damage to the steering wheel.

[0006] In order to achieve the above object, the present invention provides a pseudo obstacle transporting device that travels while carrying a pseudo obstacle, the obstacle transporting device having a steering wheel that controls the traveling direction, a housing that covers the steering wheel, and a steering power unit that is connected to the housing and applies an external force to the steering wheel to change the traveling direction, and the steering wheel is configured to come into contact with the ground on the extension of its steering axis.

[0007] According to the present invention, the external force applied to the steering wheel when the steering wheel interferes with the vehicle can be reduced, thereby suppressing damage to the steering wheel.

[0008] 8 is a perspective view showing the external configuration of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 9 is a bottom view of the external configuration of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 10 is an exploded view of a housing and a traveling device of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 11 is a diagram showing the height relationship between the overall height of a simulated obstacle transporting device according to one embodiment of the present invention and the minimum ground clearance of a vehicle to be tested. FIG. 12 is a schematic view showing the operating mode of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 13 is a schematic view showing the operating mode of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 14 is a schematic view showing the operating mode of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 15 is a schematic view showing the operating mode of a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 16 is a schematic view showing a performance test of a vehicle using a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 17 is a rear view of the steering wheel provided in a simulated obstacle transporting device according to one embodiment of the present invention. FIG. 18 is a cross-sectional view taken along line VIII-VIII in FIG. 9, viewed in the same direction as FIG. 7. FIG. 19 is a cross-sectional view taken along line IX-IX in FIG. 8. FIG. 19 is a plan view of a steering wheel provided in a simulated obstacle transporting device according to one embodiment of the present invention. 10 is a cross-sectional view of XIa in FIG. 10 taken along line XIb-XIb in FIG. 9. FIG. 11 is a bottom view of a steering wheel provided in a pseudo obstacle transporting device according to one embodiment of the present invention. FIG. 12 is an enlarged cross-sectional view of part XIIIa in FIG. 9 taken along line XIIIb-XIIIb in FIG. 10. FIG. 13 is an explanatory diagram of the effect of one embodiment of the present invention. FIG. 14 is an explanatory diagram of a problem in a comparative example.

[0009] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0010] - Pseudo Obstacle Transporting Device - Figure 1 is a perspective view showing the external configuration of a pseudo obstacle transporting device according to one embodiment of the present invention, Figure 2A is a bottom view thereof, and Figure 2B is an exploded view thereof. Also, Figure 3 is a diagram showing the height relationship between the overall height of the pseudo obstacle transporting device shown in Figure 1 and the minimum ground clearance of the vehicle being tested, and Figures 4A to 4D are schematic diagrams showing the operational form of the pseudo obstacle transporting device. The right, left, bottom, and top of Figure 2A correspond to the front, rear, left, and right of the pseudo obstacle transporting device 1 (hereinafter abbreviated as transporting device 1) of this embodiment.

[0011] The transport device 1 shown in FIG. 1 and other figures is a device that stops or moves while carrying a simulated obstacle B, which is a dummy obstacle used in performance tests of a vehicle (test vehicle) A, to simulate a static or dynamic obstacle. The body of the simulated obstacle B is generally made of a soft material such as a balloon, so that even if the vehicle A collides with the simulated obstacle B during a performance test, the simulated obstacle B and the vehicle A are unlikely to be damaged. The performance test tests, for example, the functions of the vehicle A's autonomous driving (AD) and advanced driver-assistance systems (ADAS). The transport device 1 is configured to be low-profile and thin so as to be unlikely to be recognized as an obstacle by the external recognition sensor of the vehicle A under test and to avoid contact with the body of the vehicle A when the vehicle A collides with the simulated obstacle B. As shown in FIG. 3, the overall height of the transport device 1 from the ground surface is kept lower than the minimum ground clearance H of the vehicle A, for example, approximately 100 mm.

[0012] As components, the transport device 1 includes a running device 2 (FIG. 2A), a housing 3, and connection portions 4 and 5, etc.

[0013] The traveling device 2 is a device that allows the transporter 1 to travel under its own power, and the transporter 1 is equipped with a plurality of traveling devices (three in this embodiment) (drive wheels 2L, 2R and steering wheel 2F. These drive wheels 2L, 2R and steering wheel 2F each include one wheel 25. The transporter 1 of this embodiment is configured to brake using only the regeneration of the drive motors of the drive wheels 2L, 2R, and is made smaller by omitting a mechanical brake. Furthermore, the transporter 1 omits a suspension mechanism in anticipation of travel on paved roads such as a test course, making it even smaller. However, it is possible to install mechanical brakes or suspension mechanisms as necessary.

[0014] The steering wheel 2F is a driven wheel (which may also be a drive wheel) that controls the traveling direction of the transporter 1 and is located in the front center of the housing 3. The drive wheel 2L is located on the rear left side of the left housing 3, and the drive wheel 2R is located on the rear right side of the housing 3. Specifically, the drive wheels 2L and 2R are located in the rear corners of the main body 3a of the housing 3, and the steering wheel 2F is located near the front inner wall of the main body 3a of the housing 3. In this way, the wheelbase and tread are maximized within the limited space inside the main body 3a of the housing 3, improving straight-line stability. In this embodiment, the transporter 1 is driven by the drive wheels 2L and 2R, which are the rear wheels, and steered by the steering wheel 2F, which is the front wheel. However, it is possible to add a steering mechanism to the drive wheels 2L and 2R, or to add a traveling drive mechanism to the steering wheel 2F.

[0015] Furthermore, to further enhance the straight-line stability of the transport device 1, an area X for mounting relatively heavy control equipment is provided in the triangular area S surrounded by the drive wheels 2L, 2R and steering wheel 2F. Furthermore, left and right areas Y for mounting batteries and left and right areas Z for mounting other electronic devices are arranged in front of the left and right drive wheels 2L, 2R, on either side of area X and the steering wheel 2F. Furthermore, the transport device 1 is a tricycle that runs on a total of three wheels 25, each consisting of the steering wheel 2F and the drive wheels 2L, 2R, and because the three wheels 25, spaced apart at three locations, are always in contact with the ground, no height adjustment mechanism for the wheels 25 is required.

[0016] The housing 3 is the body of the transport device 1, has connection parts 4 and 5 for connecting the dummy obstacle B, and covers the traveling device 2. In this embodiment, the housing 3 is configured to include a main body part 3a (core block) and a slope part 3b (cover). The housing 3 can be configured as an assembly of the main body part 3a and the slope part 3b, with the main body part 3a and the slope part 3b being separate structures, or the main body part 3a and the slope part 3b can be configured as an integrally molded structure.

[0017] In this embodiment, the main body 3a has a thin, box-like shape that is rectangular (square in the illustrated example) in plan view, has front, rear, left, and right sides, a top surface, and is open at the bottom. In this embodiment, the top surface (top surface) of the main body 3a is a horizontal plane, but this is not necessarily the case. The main body 3a is made of metal and has high strength enough to withstand the load even when run over by the automobile A. Although not shown in FIG. 2A , ribs may be provided appropriately inside the main body 3a (the volume space surrounded by the front, rear, left, and right sides and the top surface) to improve the strength of the main body 3a.

[0018] The sloped surface 3b is located on the outer periphery of the main body 3a and surrounds the entire periphery of the main body 3a. In this embodiment, the sloped surface 3b is detachably attached to the front, rear, left, and right sides of the main body 3a. The upward surface of the sloped surface 3b is a sloped surface that slopes downward from the horizontal center of the housing 3 toward the outside, and descends from the top surface of the main body 3a toward the ground surface. The inclination angle, etc. of this sloped surface is set so that the wheels of the automobile A can smoothly climb onto the transport device 1 when the automobile A collides with the simulated obstacle B. The sloped surface 3b is a replaceable part and is made of lightweight resin. Figure 2A illustrates a structure in which the sloped surface 3b is hollowed out to reduce weight.

[0019] The connection unit 4 is a mechanism for fixing the dummy obstacle B to the housing 3 and is provided on the upper part of the housing 3, for example, in the center of the top surface. The configuration of the connection unit 4 is appropriately adopted depending on the mechanism for attaching and detaching the dummy obstacle B to the transport device 1. The connection unit 4 illustrated in FIG. 1 is a mechanism similar to a clamp that holds down the base plate of a pole (pipe, etc.). The dummy obstacle B is fixed to the transport device 1 by attaching it to a pole supported by the connection unit 4 or by fastening the dummy obstacle to the pole. Alternatively, the connection unit 4 can be configured with threaded holes into which bolts for fixing the dummy obstacle B are screwed. The configuration of the connection unit 4 can be modified in various ways. The connection unit 5 utilizes a magnet and fixes the dummy obstacle B by attracting an iron plate attached to the bottom of the dummy obstacle B. Both connection units 4 and 5 do not necessarily need to be provided; either one may be omitted. The layout of the connection units 4 and 5 can also be modified as appropriate. A dummy obstacle B is attached to the top of the housing 3 of the transport device 1 via these connection parts 4 and 5, and when the transport device 1 runs in this state, the movement of the obstacle imitated by the dummy obstacle B is reproduced by the transport device 1.

[0020] The dummy obstacle B is selected in a shape appropriate for the purpose of the performance test and attached to the transporter 1. Fig. 4A shows an example in which a dummy obstacle B simulating a pedestrian B1 is mounted on the transporter 1. Fig. 4B shows an example in which a bicycle B2 is mounted on the transporter 1, Fig. 4C shows an example in which a motorcycle B3 is mounted on the transporter 1, and Fig. 4D shows an example in which a car B4 is mounted on the transporter 1. The transporter 1 travels in accordance with, for example, a radio signal in response to remote control operation by an operator, a radio signal remotely controlled by a control device, or a predefined program, and reproduces the predetermined movement of the mounted dummy obstacle B.

[0021] FIG. 5 is a schematic diagram showing a performance test of automobile A using a transporter 1. In the performance test, the transporter 1 loaded with a simulated obstacle B stops or travels under test conditions specified in the performance test. The automobile A being tested travels relative to the simulated obstacle B loaded on the transporter 1, recognizing the simulated obstacle B as a real obstacle using its obstacle recognition function and activating a collision avoidance function, etc., as necessary. If the test conditions make it difficult to avoid a collision with the simulated obstacle B, the body of automobile A collides with the simulated obstacle B, as shown in FIG. 5. Participants in the performance test observe the collision between automobile A and simulated obstacle B from a location at an appropriate distance from automobile A and the transporter 1.

[0022] In such performance tests of automobile A, when automobile A collides with simulated obstacle B, the transport device 1 often gets under the body of automobile A or is run over by the wheels of automobile A. In such a usage environment, it is necessary to ensure that the running device 2 and other parts are not damaged even if run over by automobile A, so that the transport device 1 can be used repeatedly for performance tests.

[0023] -Steering wheel- Fig. 6 is a perspective view of steering wheel 2F, which is the steering wheel, Fig. 7 is a rear view of steering wheel 2F as seen in the direction of arrow VII in Fig. 6, Fig. 8 is a view seen in the same direction as Fig. 7 and is a cross-sectional view taken along line VIII-VIII in Fig. 9, and Fig. 9 is a cross-sectional view taken along line IX-IX in Fig. 8. Fig. 10 is a plan view of steering wheel 2F, Fig. 11 is a cross-sectional view of XIa in Fig. 10 taken along line XIb-XIb in Fig. 9, Fig. 12 is a bottom view of steering wheel 2F, and Fig. 13 is an enlarged cross-sectional view of part XIIIa in Fig. 9 taken along line XIIIb-XIIIb in Fig. 10.

[0024] The steering wheel 2F includes a wheel 25, a steering shaft (kingpin) 26, a first connecting mechanism 21, a second connecting mechanism 22, a third connecting mechanism 23, and a fourth connecting mechanism 24.

[0025] The wheel 25 includes a cylindrical wheel 25a and a tire 25b that covers the outer peripheral surface of the wheel 25a and comes into contact with the ground. As shown in FIG. 8 , the outer peripheral surface of the tire 25b forms a curved surface that is convex outward in a cross section cut along a plane passing through the rotation center line C1 of the wheel 25. In other words, the steered wheel 2F has a convex contact surface, and the contact area is reduced compared to when the outer peripheral surface of the tire 25b is cylindrical. In this embodiment, the contact portion 25c of the tire 25b is located on the center line C2 of the steering shaft 26, and the steered wheel 2F is configured to come into contact with the ground on an extension of the steering shaft 26. In other words, the scrub radius of the steered wheel 2F is zero. The center line C2 of the steering shaft 26 may pass through the contact portion 25c, which has an area, but it is preferable that it pass through the contact center (the center point of the contact portion 25c) of the steered wheel 2F.

[0026] The steering shaft (kingpin) 26 is housed inside the cylindrical wheel 25a of the steerable wheel 2F. Generally, the steering shaft (kingpin) is located away from the tire center to accommodate a brake rotor or the like. However, in this embodiment, the steering shaft 26 is intentionally located inside the wheel 25a of the steerable wheel 2F. In this embodiment, the steering shaft 26 extends vertically, and the center line C2 of the steering shaft 26 is perpendicular to the ground contacting the ground at the ground contact portion 25c of the steerable wheel 2F. In this manner, the steerable wheel 2F is configured so that the caster angle and caster trail are zero. The caster angle is the angle between the steering shaft and the ground contact center axis (a line perpendicular to the ground contact surface) of the steerable wheel 2F. As described above, the caster angle is zero because the center line C2 of the steering shaft 26 corresponds to the ground contact center axis of the steerable wheel 2F. Caster trail is the distance from the intersection of the extension of the steering axis 26 and the ground to the contact point 25c of the steered wheel 2F, and as mentioned above, the steered wheel 2F contacts the ground on the extension of its steering axis 26, so the caster trail is 0 mm.

[0027] The first connection mechanism 21 connects the steering shaft 26 and the housing 3. As shown in FIG. 11 , the first connection mechanism 21 includes a base 21a and an arm 21b. The base 21a and the arm 21b are integrally formed. The arm 21b extends along the rotation center line C1 of the wheels 25 when the transporter 1 is in a straight-ahead position, and supports the steering shaft 26 at its tip inserted inside the wheel 25a of the wheels 25. A cross section of the arm 21b taken perpendicular to the rotation center line C1 is vertically elongated, and as shown in FIG. 11 , in a plan view, it has a shape that tapers (becomes thinner) from the steering shaft 26 toward the sliding mechanism 27, i.e., toward the base 21a. By making the arm portion 21b thinner toward the base portion 21a within the range where the required strength is ensured, interference between the arm portion 21b and the wheel 25a during steering is suppressed, and a wide rotation angle of the wheel 25 around the steering shaft 26, i.e., a wide steering angle, is ensured.

[0028] The base 21a of the first connection mechanism 21 is connected to the housing 3 via a sliding mechanism 27 (linear guide) and is slidable in a direction perpendicular to the contact surface of the steering wheel 2F, i.e., in the vertical direction. In other words, the wheel 25 supported by the first connection mechanism 21 is configured to be able to move upward relative to the housing 3 along with the first connection mechanism 21.

[0029] The sliding mechanism 27 includes a rail 27a and a block 27b. The rail 27a is fixed to the housing 3, and the block 27b slides up and down while being guided by the rail 27a. The first connection mechanism 21 is fixed to the block 27b and moves relative to the housing 3. The steering wheel 2F is selectively held at a first fixing portion P1 or a second fixing portion P2 ( FIG. 13 ), which are at different heights, by a position fixing mechanism 28. The position fixing mechanism 28 is a plunger fixed to the housing 3, and the first fixing portion P1 or the second fixing portion P2 is a recess provided in the first connection mechanism 21 or the block 27b of the sliding mechanism 27. A pin (or ball) 28a at the tip of the position fixing mechanism 28 fits into the first fixing portion P1 or the second fixing portion P2, thereby holding the steering wheel 2F at the first fixing portion P1 or the second fixing portion P2. When traveling, the steering wheel 2F is held by the first fixing part P1 and the wheel 25 partially protrudes below the housing 3, but if an external force acts to press down on the housing 3, such as when the car A runs over the housing 3, the pin 28a comes out of the first fixing part P1 and the steering wheel 2F (wheel 25) moves upward relative to the housing 3, and the pin 28a fits into the second fixing part P2, so that the steering wheel 2F is completely housed in the housing 3. A similar mechanism is separately provided in the transport device 1 for the drive wheels 2L and 2R.

[0030] 6 and other figures, when the steering wheel 2F is fixed at the second fixing portion P2, the jig J is inserted from above the housing 3 through the through-hole 3e (FIG. 1) in the housing 3 to press down the steering wheel 2F (here, the base 21a of the first connection mechanism 21) and return the steering wheel 2F to a state where it is held at the first fixing portion P1. The upper limit of the movement range of the steering wheel 2F relative to the housing 3 is limited by a stopper 29 fixed to the housing 3, so that the steering wheel 2F does not rise beyond the second fixing portion P2.

[0031] The second connection mechanism 22 connects the steering shaft 26 and the steering power unit 30. The steering power unit 30 is a power unit, such as a servo motor, that applies an external force to the steering wheel 2F to change the traveling direction of the transporter 1, and is connected and fixed to the housing 3. As shown in Fig. 8, this second connection mechanism includes a wheel unit 22a that connects to the wheel 25a of the steering wheel 2F, a wheel axle 22b that connects to the steering shaft 26, and a bearing unit 22c that connects the wheel unit 22a and the wheel axle 22b.

[0032] The wheel portion 22a is a cylindrical member and, as shown in FIG. 8 , is integrally formed (as a single component) with the wheel 25a of the wheel assembly 25 and protrudes from the wheel assembly 25 on the side opposite the first connection mechanism 21 across the steering shaft 26. The wheel axle 22b extends along the rotation center line C1 of the wheel assembly 25 and is inserted into the wheel 25a of the wheel assembly 25 from the side opposite the arm portion 21b of the first connection mechanism 21. The wheel axle 22b is connected to the steering shaft 26 located inside the wheel 25a of the wheel assembly 25 on the side opposite the first connection mechanism 21 across the steering shaft 26. The bearing portion 22c is a hub bearing located on the outside of the wheel assembly 25 and rotatably couples the wheel portion 22a to the wheel axle 22b around the rotation center line C1. This allows the wheel assembly 25 to rotate freely relative to the wheel axle 22b. By disposing the bearing portion 22 c , which is a hub bearing, on the outside of the wheel 25 , a space for disposing the steering shaft 26 is secured inside the wheel 25 .

[0033] As the second connection mechanism 22 swings horizontally around the steering shaft 26, the wheels 25 rotate horizontally around the steering shaft 26 in conjunction with the second connection mechanism 22, and the traveling direction of the transport device 1 is controlled.

[0034] In this embodiment, the second connection mechanism 22 is not directly connected to the steering power unit 30, but is connected to the steering power unit 30 via a third connection mechanism 23 and a fourth connection mechanism 24. The third connection mechanism 23 is a knuckle arm that connects the second connection mechanism 22 and the fourth connection mechanism 24. The third connection mechanism 23 has a threaded portion that is fixed to the wheel axle 22b of the second connection mechanism 22 (FIG. 8). The fourth connection mechanism 24 connects the third connection mechanism 23 and the steering power unit 30 and is tiltable. Specifically, the fourth connection mechanism 24 includes a link shaft 24a and a rod end bearing 24b. The link shaft 24a is fixed to the output shaft of the steering power unit 30. One end of the rod end bearing 24b is rotatably connected to an end of the link shaft 24a, and the other end is rotatably connected to an end of the third connection mechanism 23 via a ball joint. When the third connection mechanism 23 moves to the upper limit relative to the link shaft 24a, the rod end bearing 24b tilts up and down. As a result, the vertical movement of the steering wheel 27 (movement between the first fixed part P1 and the second fixed part P2) caused by the sliding mechanism 27 is absorbed by the tilting of the rod end bearing 24b and is not transmitted to the steering power part 30.

[0035] -Effects- (1) When the steering axis α is located outside the steered wheel β as in the comparative example shown in Figure 15, if the transport device is dragged by the automobile A, the moment acting on the wheel X25 due to this dragging will be transmitted to the steering power unit δ via the connection mechanism γ, and there is a possibility that the steering power unit δ will be damaged.

[0036] In contrast, in this embodiment, the steering wheel 2F is configured to contact the ground on an extension of the steering shaft 26, and the scrub radius is substantially zero. In other words, as shown in Fig. 14, even if the transporter 1 interferes with the automobile A and is dragged, there is a point of action (grounding point) on the extension of the steering shaft 26, which serves as the moment center, at which an external force acts on the steering wheel 2F due to the drag, so the moment acting on the steering wheel 2F around the steering shaft 26 can be suppressed. This makes it possible to suppress the application of an external force from the steering wheel 2F to the steering power unit 30, and to suppress damage to the steering power unit 30.

[0037] (2) Even if the steering wheel 2F is unitized with the steering power unit 30 and the entire unit rotates around the center of contact with the ground of the steering wheel 2F, the scrub radius can be reduced to zero. However, in this case, the steering mechanism becomes larger, and in a transport device 1 where the vehicle height is restricted and there is little space in the vertical direction, the installation space for the steering mechanism must be expanded horizontally. Furthermore, because the size and weight of the rotating unit become larger, a larger steering power unit 30 is also required to achieve high torque.

[0038] In contrast, in this embodiment, the steering shaft 26 is disposed inside the wheel 25a of the steered wheel 2F, and the first connection mechanism 21 and the second connection mechanism 22 are connected to the steering shaft 26 from opposite sides thereof. The steering shaft 26 is connected to the housing 3 via the first connection mechanism 21, and the steering shaft 26 is connected to the steering power unit 30 via the second connection mechanism 22. The steering power unit 30 is fixed to the housing 3. In this way, the steering power unit 30 is fixed to the housing 3 and is not an object to be rotated, so the steering mechanism can be made smaller than in a configuration in which the steered wheel 2F is rotated together with the steering power unit 30. Furthermore, the size and weight of the object to be rotated can be kept small, and the size of the steering power unit 30 can also be reduced.

[0039] (3) Since the first connection mechanism 21 is connected to the housing 3 via a sliding mechanism 27 and the steering wheel 2F can move vertically, for example, when the transport device 1 is run over by the automobile A, the steering wheel 2F can be stored in the housing 3, thereby preventing damage to the steering wheel 2F.

[0040] (4) The second connection mechanism 22 is configured to include a wheel portion 22a that connects to the wheel 25a of the steered wheel 2F, a wheel axle 22b that connects to the steering shaft 26, and a bearing portion 22c that connects the wheel portion 22a and the wheel axle 22b. The required values ​​of power performance (acceleration and maximum speed) required of the transport device 1 in a performance test that evaluates the collision safety of the automobile A can be achieved without driving the steered wheel 2F. Therefore, in this embodiment, the steered wheel 2F is a driven wheel, and the bearing portion 22c as a hub bearing is located outside the wheel 25a, allowing the steered wheel 2F to rotate freely in the traveling direction. By locating the bearing portion 22c as a hub bearing outside the wheel 25a, space can be secured inside the wheel 25a, allowing the steering shaft 26 to be located inside the wheel 25a.

[0041] (5) In order to steer the steering wheel 2F, it is necessary to connect the steering wheel 2F to the steering power unit 30. On the other hand, the steering wheel 2F needs to be configured to be movable in the vertical direction so that the steering wheel 2F can be stored in the housing 3 when the automobile A runs onto the transport device 1, for example.

[0042] Therefore, in this embodiment, the second connection mechanism 22 is connected to the steering power unit 30 via the third connection mechanism 23 and the fourth connection mechanism 24, and the fourth connection mechanism 24 is configured to be tiltable. As a result, the vertical movement of the steered wheels 2F is absorbed by the tilt of the fourth connection mechanism 24, and damage to the steering power unit 30 caused by the transmission of an external force due to the vertical movement of the steered wheels 2F can be suppressed.

[0043] (6) By making the contact surface of the steered wheels 2F convex, the contact area of ​​the steered wheels 2F can be reduced, and the power required for steering can be reduced. This also contributes to the miniaturization of the steering power unit 30.

[0044] (7) By configuring the first connection mechanism 21 (arm portion 21b) to become thinner from the steering shaft 26 toward the sliding mechanism 27 in a plan view, the steering angle of the steering wheel 2F can be increased compared to if the arm portion 21b had a uniform thickness. In this embodiment, because the steering shaft 26 (kingpin) is located inside the wheel 25a, the maximum steering angle is limited by interference between the arm portion 21b and the wheel 25a. However, the arm portion 21a becomes thinner as it moves away from the steering shaft 26, so the necessary steering angle can be ensured. This allows the transporter 1 to have sufficient maneuverability.

[0045] (8) The steering wheel 2F is configured so that the caster angle and caster trail are 0. In a manned vehicle, if the caster angle or caster trail is 0, the maneuverability becomes too sensitive and straight-line running cannot be maintained. However, in the case of the transporter 1, since it is an unmanned vehicle, the caster angle and caster trail can be set to 0, thereby improving the agility of the transporter 1.

[0046] (9) In this embodiment, the position fixing mechanism 28 is a ball plunger, and the traveling device 2 is fixed to either the first fixing portion P1 or the second fixing portion P2 by the spring force of the ball plunger. The fact that the position fixing mechanism 28 can be easily configured using a ball plunger, which is a general-purpose device element, also contributes to making the transporting device 1 smaller and less expensive.

[0047] (10) Because the transport device 1 is a tricycle, all three wheels 25 naturally come into contact with the ground at the same time. This eliminates the need for a wheel 25 position adjustment mechanism or suspension mechanism. The road surface on which the transport device 1 travels is expected to be a paved test course or the like, so the absence of a suspension mechanism does not pose any particular problem. Eliminating the suspension mechanism and wheel 25 position adjustment mechanism offers significant benefits, such as space savings, size reduction, weight reduction, a reduced number of parts, and easier maintenance.

[0048] -Modifications- The present invention is not limited to the above-described embodiments and may include various modifications. For example, the above-described embodiments have been described in detail to clearly explain the present invention, and are not necessarily limited to those including all of the described configurations. For example, it is possible to replace some of the configurations with other configurations. It is also possible to delete some of the configurations of the embodiments or add other configurations.

[0049] DESCRIPTION OF SYMBOLS 1...dummy obstacle transporting device, 2F...steering wheel, 3...housing, 25a...wheel, 26...steering shaft, 21...first connecting mechanism, 22...second connecting mechanism, 22a...wheel portion, 22b...wheel shaft, 22c...bearing portion, 23...third connecting mechanism, 24...fourth connecting mechanism, 30...steering power portion, 27...sliding mechanism, B...dummy obstacle

Claims

1. A pseudo obstacle transport device that travels with a pseudo obstacle loaded on it, comprising: a steering wheel that controls the direction of travel; a housing that covers the steering wheel; and a steering power unit that is connected to the housing and applies an external force to the steering wheel to change the direction of travel, wherein the steering wheel is configured to contact the ground on an extension of its steering axis.

2. An obstacle transporting device as described in claim 1, wherein the steering wheel houses the steering shaft inside the wheel, and is equipped with a first connection mechanism that connects the steering shaft to the housing, and a second connection mechanism that connects the steering shaft to the steering power unit, and the second connection mechanism connects to the steering shaft located inside the wheel from the opposite side to the first connection mechanism, across the steering shaft.

3. An obstacle transporting device as described in claim 2, wherein the first connection mechanism is connected to the housing via a sliding mechanism and is slidable in a direction perpendicular to the contact surface of the steering wheel.

4. An obstacle transporting device as described in claim 2, characterized in that the second connection mechanism has a wheel section connected to the wheel, a wheel axle connected to the steering shaft, and a bearing section connecting the wheel section and the wheel axle.

5. An obstacle transporting device as described in claim 2, characterized in that the second connection mechanism is connected to the steering power unit via a third connection mechanism that connects to the second connection mechanism, and a fourth connection mechanism that links the third connection mechanism and the steering power unit and is tiltable.

6. An obstacle transporting device according to claim 1, characterized in that the steering wheel has a contact surface having a convex shape.

7. An obstacle transporting device according to claim 3, wherein the first connection mechanism is tapered from the steering shaft toward the sliding mechanism in a plan view.

8. An obstacle transporting device according to claim 2, characterized in that the steering wheels are configured so that the caster angle and caster trail are zero.