JP4310462B2 - vehicle - Google Patents

Description

  The present invention relates to a vehicle capable of turning at a low speed, such as a wheelchair, and capable of long-distance driving at a certain high traveling speed.

Conventionally, a wheelchair and a forklift that have a pair of left and right steerable wheels that can be steered independently and a pair of left and right drive wheels that can be independently steered, and that can be swung freely at a low speed by operating an operation member such as a joystick. Such vehicles are known (see, for example, Patent Documents 1 to 3). A forklift that can move the center of gravity of the vehicle body by changing the distance between the front wheel and the rear wheel, that is, the wheel base, is also known (see, for example, Patent Document 4).
Japanese Patent Laid-Open No. 9-294779 Japanese Patent Application Laid-Open No. 5-116643 JP 2002-362889 A JP 2001-48497 A

  However, in the former conventional device, the distance (wheel base) between the steered wheel and the drive wheel is very short, and cannot stably travel at a certain high speed. Even in the latter conventional apparatus, the wheel base is made variable in order to change the position of the center of gravity, and is not intended to run stably at a certain high speed.

  An object of the present invention is to provide a vehicle that can be swung freely like a wheelchair and can travel at a low speed on a sidewalk, in a building, etc., and at the same time can travel on a general road at a somewhat high speed for long-distance driving. It is something to try.

In order to achieve the above object, the present invention is characterized by a pair of steering means for independently turning a pair of left and right steered wheels, a pair of drive means for independently driving a pair of left and right drive wheels, A driving operation member for driving the vehicle, and a pair of steered means and a pair of driving means are controlled according to the operation state of the driving operation member to steer the pair of steered wheels and drive the pair of drive wheels. In a vehicle provided with driving control means, a telescopic mechanism capable of changing the distance between the pair of steered wheels and the pair of driving wheels is provided, and the driving control means is operated in conjunction with the change of the distance by the telescopic mechanism. in to change the portion of the steering aspects and a pair of drive wheels of a drive mode of a pair of steerable wheels in accordance with the operation state of the thing. In this case, for example, a joystick capable of two-dimensional displacement can be adopted as the driving operation member, and the driving control means controls the driving of the pair of driving wheels according to the displacement of the joystick in the first direction, and the first of the joysticks The turning of the pair of steered wheels may be controlled according to the displacement in the second direction different from the one direction.

  Further, when the operation control means is switched to a state in which the distance between the pair of steered wheels and the pair of drive wheels is short, for example, by an expansion / contraction mechanism, compared to when the distance is switched to a long state It is good to have a steering control means which accept | permits the turning angle of a pair of turning wheel according to operation of a member to a big value. And when this steering control means is switched to a state where the distance between the pair of steered wheels and the pair of drive wheels is short by the expansion / contraction mechanism, the steered angle of the pair of steered wheels according to the operation of the operation member is It is preferable to increase the turning angle difference between the pair of steered wheels as it increases.

  Further, when the operation control means is switched to a state in which the distance between the pair of steered wheels and the pair of drive wheels is long by the expansion / contraction mechanism, the pair of drive wheels are driven in the same direction, and the pair of steered wheels by the expansion / contraction mechanism. When the distance between the drive wheel and the pair of drive wheels is switched to a short state, it is preferable to have drive control means capable of driving the pair of drive wheels in the same direction and in opposite directions. In addition, when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the telescopic mechanism, the operation control means increases the steered angle of the pair of steered wheels according to the operation of the operation member. Accordingly, it is preferable to have drive control means for increasing the rotational speed difference between the pair of drive wheels. And these drive control means, when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the expansion / contraction mechanism, the pair of drive control means in the state where the pair of steered wheels are steered small In a state where the wheels are driven in the same direction and the pair of steered wheels are largely steered, the pair of drive wheels may be driven in opposite directions.

According to the characteristics of the present invention configured as described above, the pair of steered wheels and the pair of drive wheels are short and long in accordance with the operation state of the driving operation member. some of the steering aspects and a pair of driving wheels of the driving mode of the steered wheels of the changes. Therefore, in the vehicle according to the present invention, it is possible to achieve both running stability and small turning performance, and can turn freely like a wheelchair and can run at a low speed on a sidewalk, in a building, etc. This makes it possible to drive for long distances and to use both a normal vehicle and a special vehicle such as a wheelchair. Specifically, as described above, traveling stability is ensured by reducing the maximum turning angle of the pair of steered wheels while the distance between the pair of steered wheels and the pair of drive wheels is long. Conversely, the small turning performance of the vehicle can be improved by increasing the maximum turning angle of the pair of steered wheels while the distance between the pair of steered wheels and the pair of drive wheels is short. In particular, as the turning angle of a pair of steered wheels increases, the difference in turning angle between the same pair of steered wheels increases, the difference in rotational speed between a pair of drive wheels increases, If driven in the opposite direction, the turning radius can be made extremely small and in-situ turning is possible.

  Another feature of the present invention is that the operation control means torque-controls the pair of drive wheels when the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state by the extension mechanism. Thus, there is provided drive system control means for controlling the speed of the pair of drive wheels when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state.

  According to this, when the distance between the pair of steered wheels and the pair of drive wheels is set to a long state, the pair of drive wheels are torque-controlled, and in this state, as a normal vehicle, Driving on the road makes it possible to drive in the same way as a normal vehicle. Also, when the distance between the pair of steered wheels and the pair of drive wheels is set to be short, the speed of the pair of drive wheels is controlled, so that the occupant can easily reduce the speed at a low speed like a wheelchair. Can be controlled. Therefore, the vehicle is driven with characteristics suitable for the switching state by the expansion / contraction mechanism, and the occupant can easily drive the vehicle according to the present invention.

  Another feature of the present invention is that a mechanical braking device is provided for the pair of steered wheels, the pair of drive means is constituted by an electric motor, and the operation control means is connected to the pair of steered wheels by a telescopic mechanism. When the distance to the driving wheel is switched to a long state, the mechanical braking device is operated according to the operation of the driving operation member, and the braking force is applied to the pair of driving wheels by regenerative braking by the electric motor. In addition, when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the telescopic mechanism, the regenerative braking by the electric motor is performed according to the operation of the driving operation member without operating the mechanical braking device. Therefore, a braking control means for applying a braking force to the pair of drive wheels is provided.

  According to this, when the distance between the pair of steered wheels and the pair of drive wheels is set to be long, both the mechanical braking device for the pair of steered wheels and the regenerative brake for the pair of drive wheels, Since sufficient braking force is applied to the vehicle, safety is kept high even when traveling on a general road like a normal vehicle in this state. In addition, when the distance between the pair of steered wheels and the pair of drive wheels is set to a short state, the braking force is applied to the vehicle only by regenerative braking on the pair of drive wheels. Sudden deceleration can be avoided and high safety is maintained. In particular, when the vehicle in this state is used like a wheelchair, the position of the center of gravity of the vehicle becomes high, and the occupant tends to fall forward when braking the vehicle, but such a situation can be prevented in advance.

  Another feature of the present invention is that when the operation control means is switched to a state where the distance between the pair of steered wheels and the pair of drive wheels is long by the telescopic mechanism, the joystick is displaced forward from the neutral position. Accordingly, the rotation of the pair of driving wheels is accelerated, the rotation of the pair of driving wheels is braked according to the displacement from the neutral position of the joystick to the rear, and the distance between the pair of steered wheels and the pair of driving wheels by the telescopic mechanism. Is switched to a short state, the pair of drive wheels are rotated forward according to the displacement from the neutral position of the joystick to the front, and the pair of drive wheels are rotated backward according to the displacement from the neutral position of the joystick to the rear. The driving direction control means is provided.

  According to this, when the distance between the pair of steered wheels and the pair of drive wheels is set to be long, the acceleration and deceleration of the vehicle are controlled by the forward / backward operation of the joystick. If the vehicle travels on a general road like this vehicle, the same driving as a normal vehicle becomes possible. In addition, when the distance between the pair of steered wheels and the pair of drive wheels is set to a short state, the forward and backward movement is controlled by the forward / backward operation of the joystick, so the occupant can easily operate this vehicle. it can. Therefore, the vehicle is driven with characteristics suitable for the switching state by the expansion / contraction mechanism, and the occupant can easily drive the vehicle according to the present invention.

Another feature of the present invention is that when the telescopic mechanism is switched to a state where the distance between the pair of steered wheels and the pair of drive wheels is long, compared to when the distance is switched to a short state. The inclination angle with respect to the road surface of the seat on which the passenger is seated is reduced. In addition, when the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state, the telescopic mechanism has an inclination angle with respect to the road surface of the vehicle body as compared to when the distance is switched to a short state. It may be made smaller. In these vehicles in which the inclination of the seat or the vehicle body is changed, the distance between the inclination angle sensor that detects the inclination angle of the seat or the vehicle body with respect to the road surface, and the pair of steered wheels and the pair of drive wheels is short. If the tilt angle detected by the tilt angle sensor is abnormal, the telescopic mechanism is controlled so that the distance between the pair of steered wheels and the pair of drive wheels becomes long. Forcibly controlling means for forcibly controlling may be provided.

According to these, when the distance between the pair of steered wheels and the pair of drive wheels is set to a long state, the center of gravity of the vehicle and the occupant is lowered, so that the vehicle can travel stably. become. In addition, if the forward operation of the joystick is set to acceleration control forward of the vehicle, it is possible to prevent the passenger from performing the acceleration control operation by leaning forward during braking, and the abnormal behavior of the vehicle is prevented. Can be avoided. Also, when the distance between the pair of steered wheels and the pair of drive wheels is set to a short state, if this vehicle is used like a wheelchair, the upper body of the occupant will be raised, so driving operability is good become. Also, the forced control means can avoid an abnormal inclination of the seat or the vehicle body when the distance between the pair of steered wheels and the pair of drive wheels is instructed to be in a short state, and can avoid an unstable state of the occupant .

  Hereinafter, a vehicle according to an embodiment of the present invention will be described with reference to the drawings. 1 is a schematic side view showing an extended state of the vehicle according to the embodiment, FIG. 2 is a schematic side view showing a contracted state of the vehicle, and FIG. 3 is a schematic perspective view showing an extended state of the vehicle. is there.

  This vehicle has a box-shaped vehicle body BD, and a pair of left and right steered wheels WHfl and WHfr corresponding to the front wheels of the vehicle are assembled to the front side portion thereof, and the rear side portion corresponds to the rear wheel of the vehicle. A pair of left and right drive wheels WHrl and WHrr are assembled. A seat 11 on which an occupant sits is assembled in the vehicle body BD. The seat 11 includes a seating portion 11a fixed to the vehicle body BD, and a relatively long headrest portion 11b that is allowed to slightly rotate with respect to the seating portion 11a above the seating portion 11a. The vehicle body BD is provided with an operation panel 12, and the operation panel is provided with a joystick 13, an extension switch 14 and a reverse switch 15 that are operated by a passenger.

  The joystick 13 is a two-dimensionally displaceable operation unit that instructs driving and braking of the vehicle according to the longitudinal displacement from the neutral position, and commands the vehicle steering according to the lateral displacement from the neutral position. The telescopic switch 14 is a selection switch for switching the vehicle to either the extended state of FIG. 1 or the contracted state of FIG. The reverse switch 15 is a change-over switch for switching the traveling direction of the vehicle from forward to backward when the extended state is selected by the telescopic switch 14.

  The steered wheels WHfl and WHfr are steered independently by the steered devices 20a and 20b. As shown in FIG. 4, the steered devices 20 a and 20 b include electric motors 22 a and 22 b, worms 23 a and 23 b, and wheels 24 a and 24 b housed in casings 21 a and 21 b assembled on both sides of the vehicle body BD, respectively. In addition, the rotary plates 25a and 25b are provided below the casings 21a and 21b. The electric motors 22a and 22b incorporate a speed reducer, and the worms 23a and 23b rotate integrally with the output shafts 26a and 26b at the tip ends of the output shafts 26a and 26b of the electric motors 22a and 22b via the speed reducer. It is assembled like this. The worms 23a and 23b mesh with the outer peripheral gears of the wheels 24a and 24b. The rotating shafts 27a and 27b of the wheels 24a and 24b protrude downward from the lower surfaces of the casings 21a and 21b and are connected to rotate integrally with the rotating plates 25a and 25b.

  Support plates 28a and 28b having a U-shaped cross section are fixed to the lower surfaces of the rotary plates 25a and 25b. The support plates 28a, 28b support the steered wheels WHfl, WHfr so as to be rotatable about their axes via the rotating shafts 29a, 29b of the steered wheels WHfl, WHfr at the lower part of both arms extending downward. At the same time, the steered wheels WHfl and WHfr are supported so as to rotate integrally around their vertical axes. Thus, the steered wheels WHfl and WHfr are steered independently to the left and right with respect to the traveling direction of the vehicle by the rotation of the electric motors 22a and 22b. As will be described later, the casings 21a and 21b have the rotating plates 25a and 25b always horizontal with respect to the road surface, that is, the rotation shafts 27a and 27b are always perpendicular to the road surface, even if the inclination angle of the vehicle body BD changes. Thus, the vehicle body BD is connected by a connection mechanism (not shown). In other words, the vehicle body BD is rotatably assembled to the casings 21a and 21b that are wheel side members. Further, as will be described later in detail, a mechanical braking device is assembled to the steered wheels WHfl and WHfr.

  The drive wheels WHrl and WHrr are assembled to the rotary shafts of the electric motors 32a and 32b fixed to the left and right sides of the rectangular frame 31 so as to be integrally rotatable. The electric motors 32a and 32b have a built-in speed reducer, and drive wheels WHrl and WHrr are driven independently by their rotation.

  The frame 31 is supported by the vehicle body BD so as to be swingable via a link mechanism including a pair of left and right first links 33a and 33b, second links 34a and 34b, third links 35a and 35b, and fourth links 36a and 36b. Has been. The first links 33a and 33b are rotatably connected to the vehicle body BD at one end, and are rotatably connected to the rear end portion of the frame 31 at the other end. The second links 34a and 34b are respectively connected to the vehicle body BD so as to be rotatable at one end, and are respectively connected to the front end portion of the frame 31 so as to be rotatable at the other end. The third links 35a and 35b are rotatably connected to the vehicle body BD at one end, and are rotatably connected to both ends of the connecting shaft 37 at the other end. The fourth links 36a and 36b are rotatably connected to both ends of the connecting shaft 37 at one end, and are rotatably connected to intermediate positions of the second links 34a and 34b at the other end.

  A female screw hole is formed at the center position of the connecting shaft 37, and a screw rod 41 is screwed through the female screw hole. The base end of the screw rod 41 is rotationally driven around the axis by an electric motor 42 with a built-in speed reducer. The electric motor 42 is rotatably supported by the vehicle body BD via the bracket 43. The screw rod 41 constitutes a screw mechanism in cooperation with a female screw hole provided at the center position of the connection shaft 37, and the connection shaft 37 moves in the front-rear direction of the vehicle body BD by the rotation of the electric motor. Then, the distance between the drive wheels WHrl and WHrr and the steered wheels WHfl and WHfr is changed by the link mechanism. That is, when the connecting shaft 37 moves rearward of the vehicle body BD, the distance between the drive wheels WHrl, WHrr and the steered wheels WHfl, WHfr increases, and the vehicle body BD is tilted horizontally together with the seat 11 (see FIG. 1). ). That is, the inclination angle with respect to the road surface of the longitudinal axis of the vehicle body BD becomes small. Conversely, when the connecting shaft 37 moves forward of the vehicle body BD, the distance between the drive wheels WHrl and WHrr and the steered wheels WHfl and WHfr decreases, and the vehicle body BD stands up with the seat 11 on the vertical side (see FIG. 2). ). That is, the inclination angle with respect to the road surface of the longitudinal axis of the vehicle body BD is increased.

  Next, the electric control apparatus for the vehicle will be described. As shown in FIG. 5, the electric control device includes a controller 50. The controller 50 includes a microcomputer including a CPU, ROM, RAM, and the like as main components, and controls the operation of the vehicle by executing the programs shown in FIGS. In addition to the telescopic switch 14 and the reverse switch 15, the controller 50 is connected to a front / rear position sensor 51 and a left / right position sensor 52, and various drive circuits 53, 54a, 54b, 55a, 55b, 56a, 56b are also connected. It is connected. A battery 57 is connected to the controller 50 and the drive circuits 53, 54a, 54b, 55a, 55b, 56a, and 56b.

  The front / rear position sensor 51 detects the displacement position of the joystick 13 in the front / rear direction. The front-rear position sensor 51 outputs a signal that represents a forward displacement from the neutral position of the joystick 13 as 0 to +100, and a rearward displacement from the neutral position of the joystick 13 as 0 to −100. The left / right position sensor 52 detects the displacement position of the joystick 13 in the left / right direction. The left / right position sensor 52 outputs a signal that represents a rightward displacement from 0 to +100 from the neutral position of the joystick 13 and a leftward displacement from 0 to −100 from the neutral position of the joystick 13.

  The expansion / contraction motor drive circuit 53 drives and controls the expansion / contraction electric motor 42. An angle sensor 61 that detects the angles of the links 33a and 33b with respect to the vehicle body BD is connected to the extension motor drive circuit 53. The telescopic motor drive circuit 53 rotates the electric motor 42 in cooperation with the angle sensor 61 in accordance with an instruction from the controller 50 to extend the vehicle body BD (see FIG. 1) or contracted state (see FIG. 2). Switch to. The angle sensor 61 detects the inclination angle of the vehicle body BD and the seat 11 with respect to the road surface, and may detect the rotation angle of the other links 34a, 34b or 35a, 35b instead of the links 33a, 33b.

  The brake drive circuits 54a and 54b drive and control the electromagnetic brake devices 70a and 70b, which are mechanical brake devices. The electromagnetic brake devices 70a and 70b include disks 71a and 71b, brake pads 72a and 72b, and electromagnetic solenoids 73a and 73b. The disks 71a and 71b are fixed to the rotation shafts of the left and right steered wheels WHfl and WHfr so as to rotate integrally with the left and right steered wheels WHfl and WHfr. The brake pads 72a and 72b are pressed against the disks 71a and 71b and apply mechanical braking force to the left and right steered wheels WHfl and WHfr by frictional force with the disks 71a and 71b. The electromagnetic solenoids 73a and 73b drive the brake pads 72a and 72b by energization by the brake drive circuits 54a and 54b. The brake drive circuits 54a and 54b are also connected to current sensors 62a and 62b for independently detecting currents flowing through the electromagnetic solenoids 73a and 73b. The brake drive circuits 54a and 54b, in cooperation with the current sensors 62a and 62b, cause the currents instructed by the controller 50 to flow through the electromagnetic solenoids 73a and 73b in accordance with the magnitudes of the currents. The applied braking force is applied to the left and right steered wheels WHfl and WHfr. In place of the electromagnetic solenoids 73a and 73b, an electric motor may be used, or the electromagnetic brake devices 70a and 70b may be a drum type instead of a disk type. Further, instead of the current sensors 62a and 62b, a torque sensor for detecting the braking torque for the left and right steered wheels WHfl and WHfr, or a pressure sensor for detecting the braking pressure applied to the disks 71a and 71b from the brake pads 72a and 72b is used. May be.

  The steered motor drive circuits 55a and 55b drive and control the steered electric motors 22a and 22b. The steered motor drive circuits 55a and 55b are respectively connected with steered angle sensors 63a and 63b for independently detecting the steered angles of the left and right steered wheels WHfl and WHfr. Then, the steered motor drive circuits 55a and 55b rotate the electric motors 22a and 22b in cooperation with the steered angle sensors 63a and 63b according to instructions from the controller 50, so that the left and right steered wheels WHfl and WHfr are arbitrarily set. Steer to an angle.

  The drive motor drive circuits 56a and 56b drive and control the drive electric motors 32a and 32b. The drive motor drive circuits 56a and 56b are connected to current sensors 64a and 64b for independently detecting currents flowing through the electric motors 32a and 32b, respectively, and the rotational speeds of the left and right drive wheels WHrl and WHrr are respectively determined. Independently detecting rotational speed sensors 65a and 65b are connected to each other. The drive motor drive circuits 56a and 56b drive the left and right drive wheels WHrl and WHrr by controlling the torque of the electric motors 32a and 32b in cooperation with the current sensors 64a and 64b according to instructions from the controller 50, or The left and right drive wheels WHrl and WHrr are driven by controlling the rotation speed of the electric motors 32a and 32b in cooperation with the rotation speed sensors 65a and 65b. Further, the drive motor drive circuits 56a and 56b perform regenerative braking control on the electric motors 32a and 32b according to an instruction from the controller 50, and apply a regenerative braking force to the left and right drive wheels WHrl and WHrr. Further, instead of the current sensors 64a and 64b, torque sensors that detect driving torque and braking torque for the left and right driving wheels WHrl and WHrr may be used.

  Next, the operation of the vehicle according to the embodiment configured as described above will be described. In this vehicle, when a power switch (not shown) is turned on, the controller 50 starts to repeatedly execute the program of FIG. 6 every predetermined short time. The execution of this program is started in step S10, and the controller 50 inputs detection signals from the front / rear position sensor 51 and the left / right position sensor 52 and inputs signals from the telescopic switch 14 and the reverse switch 15 in step S12. .

  Next, in step S14, it is determined whether or not the expansion switch 14 is on the expansion side. If the expansion / contraction switch 14 is switched to the expansion side, “Yes” is determined in step S14, and an instruction for switching to the expansion side is output to the expansion motor drive circuit 53 in step S16. As a result, the expansion motor drive circuit 53 rotates the electric motor 42 until the inclination angle of the vehicle body BD and the road surface of the seat 11 from the angle sensor 61 becomes an angle corresponding to the extended state of the vehicle (see FIG. 1). Control. The rotation of the electric motor 42 is transmitted to the screw rod 41, and the screw rod 41 rotates around the axis. By this rotation, the connecting shaft 37 is pushed rearward, and the left and right drive wheels WHrl and WHrr are opposite to the left and right steered wheels WHfl and WHfr by the link mechanism including the links 33a, 33b, 34a, 34b, 35a, 35b, 36a, and 36b. That is, it moves backward. As a result, the vehicle is set in the extended state, the vehicle body BD and the seat 11 are tilted, and the inclination angle with respect to the road surface is reduced. If the expansion / contraction switch 14 has been on the expansion side from before, the expansion state control routine in step S18 is executed without executing substantial processing in step S16, and the execution of this program is terminated in step S24. To do.

  On the other hand, if the expansion / contraction switch 14 is switched to the contraction side, “No” is determined in step S14, and an instruction for switching to the contraction side is output to the expansion motor drive circuit 53 in step S20. Thereby, the drive circuit 53 for the telescopic motor rotates the electric motor 42 until the inclination angle of the vehicle body BD and the road surface of the seat 11 from the angle sensor 61 becomes an angle corresponding to the contracted state of the vehicle (see FIG. 2). Control. The rotating direction of the electric motor 42 is opposite to that in the above case. In this case as well, the screw rod 41 is rotated around the axis by the electric motor 42, the connecting shaft 37 is pulled forward, and the link mechanism comprising the links 33a, 33b, 34a, 34b, 35a, 35b, 36a, 36b The drive wheels WHrl and WHrr move to the left and right steered wheels WHfl and WHfr, that is, forward. As a result, the vehicle is set in a contracted state, the vehicle body BD and the seat 11 are raised, and the inclination angle with respect to the road surface is increased. If the expansion / contraction switch 14 has been on the contraction side from before, the expansion state control routine in step S22 is executed without executing substantial processing in step S22, and the execution of this program is terminated in step S24. To do.

  Next, the traveling operation of the vehicle by executing the extension state control routine will be described. As shown in FIG. 7, this extension state control routine is started in step S30, and a target turning angle calculation process is executed in step S32. In this target turning angle calculation process, the target turning angle corresponding to the input signal representing the left / right position of the joystick 13 is calculated with reference to a first turning angle table provided in the controller 50. As shown in FIG. 9, the first turning angle table moves from the neutral position to the right (in accordance with the displacement from the neutral position of the joystick 13 to the right (ie, the displacement from “0” to a positive predetermined value)). That is, the target turning angle that gradually changes from “0” to a positive predetermined value) is stored, and the joystick 13 is displaced leftward from the neutral position (that is, from “0” to a negative predetermined value). The target turning angle that gradually changes from the neutral position to the left direction (that is, a predetermined negative value from “0”) is stored.

  Next, in step S34, the calculated target turning angle is output to the turning motor drive circuits 55a and 55b. The steered motor drive circuits 55a and 55b control the rotation of the electric motors 22a and 22b until the steered angle detected by the steered angle sensors 63a and 63b reaches the target steered angle. By the rotation of the electric motors 22a and 22b, the left and right steered wheels WHfl and WHfr are steered to the target turning angle. In this embodiment, the left and right steered wheels WHfl and WHfr have the same steered angle, but the steered angle of the steered wheel corresponding to the turning inner wheel is slightly larger than the steered angle of the steered wheel corresponding to the turning outer wheel. You may make it enlarge only.

  After the process of step S34, it is determined in step S36 whether the reverse switch 15 is in the on state (reverse instruction state). If the reverse switch 15 is not in the ON state, “No” is determined in step S36, and the processes in steps S38 to S48 are executed. In step S38, it is determined whether the joystick 13 has been displaced forward from the neutral position based on the input signal from the front / rear position sensor 51. If the joystick 13 has been displaced forward from the neutral position, “Yes” is determined in step S38, and target drive torque calculation processing is executed in step S40. In this target drive torque calculation process, a target drive torque corresponding to the input signal representing the forward displacement position of the joystick 13 is calculated with reference to a drive torque table provided in the controller 50. As shown by the solid line in FIG. 10, the drive torque table shows a target drive torque that gradually increases in accordance with the forward displacement from the neutral position of the joystick 13 (ie, displacement from “0” to a positive predetermined value). I remember it.

  Next, in step S42, the calculated target drive torque is output to the drive motor drive circuits 56a and 56b, and the normal rotation of the electric motors 32a and 32b is instructed. In step S62, the execution of this program is temporarily terminated. The drive circuits 56a and 56b for the drive motor feed back the motor currents detected by the current sensors 64a and 64b, thereby controlling the torque so that the electric motors 32a and 32b generate the target drive torque. 32b is controlled to rotate forward. Therefore, the drive wheels WHrl and WHrr are driven to rotate forward with the target drive torque, and the vehicle moves forward with the same torque. At this time, if the steered wheels WHfl and WHfr are steered left and right by an operation in the left and right direction of the joystick 13, the vehicle turns left and right.

  On the other hand, if the joystick 13 is displaced rearward from the neutral position, “No” is determined in step S38, and target braking torque calculation processing is executed in step S44. In this target braking torque calculation process, a braking torque table provided in the controller 50 is referred to calculate a target braking torque corresponding to the input signal representing the rearward displacement position of the joystick 13. As shown by the solid line in FIG. 11, the braking torque table shows a target braking torque that gradually increases in accordance with the displacement from the neutral position of the joystick 13 to the rear (that is, the displacement from “0” to a negative predetermined value). I remember it.

  Next, in step S46, the calculated target braking torque is output to the brake drive circuits 54a and 54b, and the brake control is instructed. Next, in step S48, the drive motor drive circuits 56a and 56b are instructed to perform regenerative braking control on the drive wheels WHrl and WHrr. In step S62, the program is temporarily terminated. The brake drive circuits 54a and 54b feed the current proportional to the target braking torque to the electromagnetic solenoids 73a and 73b by feeding back the energization current detected by the current sensors 62a and 62b. Accordingly, the electromagnetic brake devices 70a and 70b brake the steered wheels WHfl and WHfr with the target braking torque. The drive motor drive circuits 56a and 56b perform regenerative braking control of the electric motors 32a and 32b in response to the regenerative braking instruction. As a result, the vehicle is braked by the rearward displacement of the joystick 13 by the braking torque control of the steered wheels WHfl and WHfr and the regenerative braking control of the drive wheels WHrl and WHrr.

  If the reverse switch 15 is switched to the on state while the vehicle is set in the extended state, “Yes” is determined in step S36, and the processes in steps S50 to S60 are executed. If the joystick 13 has been displaced forward from the neutral position, “Yes” is determined in step S50, and the drive torque table provided in the controller 50 is determined in step S52 as in step S40. Referring to FIG. 4, the target drive torque corresponding to the input signal representing the forward displacement position of the joystick 13 is calculated. However, the drive torque table is slightly smaller than the solid line as shown by the broken line in FIG. 10, and is displaced forward from the neutral position of the joystick 13 (ie, displacement from “0” to a positive predetermined value). The rearward target drive torque that gradually increases according to the value is stored.

  Next, in step S54, as in step S42, the calculated target drive torque is output to the drive motor drive circuits 56a and 56b, and the reverse rotation of the electric motors 32a and 32b is instructed. In step S62, the execution of this program is temporarily terminated. Also in this case, the drive motor drive circuits 56a and 56b perform torque control so that the electric motors 32a and 32b generate the target drive torque by feeding back the motor current detected by the current sensors 64a and 64b. However, the electric motors 32a and 32b are reversely controlled. Accordingly, the drive wheels WHrl and WHrr are driven in reverse rotation with the target drive torque, and the vehicle moves backward with the same torque. Also at this time, if the steered wheels WHfl and WHfr are steered left and right by an operation in the left and right direction of the joystick 13, the vehicle turns left and right.

  If the joystick 13 is displaced backward from the neutral position, “No” is determined in step S50, and the brake provided in the controller 50 is determined in step S56 as in the case of step S44. With reference to the torque table, a target braking torque is calculated in accordance with the input signal representing the rearward displacement position of the joystick 13. However, the target braking torque stored in the braking torque table is slightly smaller than that in the forward movement as shown by the broken line in FIG.

  Next, in step S58, as in the case of step S46, the brake driving circuits 54a and 54b are instructed to output the calculated target braking torque and to perform braking control. In step S60, as in step S48, the drive motor drive circuits 56a and 56b are instructed to perform regenerative braking control on the drive wheels WHrl and WHrr. In step S62, the program is temporarily terminated. Also in this case, the brake drive circuits 54a and 54b feed the current proportional to the target braking torque to the electromagnetic solenoids 73a and 73b by feeding back the energization currents detected by the current sensors 62a and 62b, thereby turning the steered wheels WHfl, WHfr is braked with the target braking torque. Also in this case, the drive motor drive circuits 56a and 56b perform regenerative braking control of the electric motors 32a and 32b in accordance with the regenerative braking instruction. As a result, the vehicle is braked by the rearward displacement of the joystick 13 by the braking torque control of the steered wheels WHfl and WHfr and the regenerative braking control of the drive wheels WHrl and WHrr.

  In this way, when the vehicle is set in the extended state, acceleration control is performed according to the amount of displacement from the neutral position of the joystick 13 to the front, and according to the amount of displacement from the neutral position of the joystick 13 to the rear. Braking control is performed (see FIG. 15A). Further, the vehicle can be moved forward and backward by switching the reverse switch 15. Then, the steered wheels WHfl and WHfr are steered by the left-right displacement of the joystick 13 to control the turning of the vehicle (see FIG. 15B). In this way, when the distance (wheel base) between the steered wheels WHfl and WHfr and the drive wheels WHrl and WHrr is set to be long, the running stability is also ensured, so that the vehicle is driven at a somewhat high speed. be able to. And since the acceleration and deceleration of the vehicle are controlled by the joystick 13, the occupant can drive the vehicle with the same feeling as a normal vehicle, and the vehicle can also drive on a general road, so it is possible to drive for a long distance. It becomes.

  Next, a case where the vehicle is switched to the contracted state will be described. In this case, the execution of the contraction state control routine of FIG. 6 is started in step S70, as shown in detail in FIG. After the start of step S70, a target turning angle calculation process is executed in step S72. In the target turning angle calculation process, the turning angle corresponding to the input signal indicating the left / right position of the joystick 13 is calculated with reference to a second turning angle table provided in the controller 50. As shown in FIG. 12, the second turning angle table is also moved from the neutral position to the right (in accordance with the displacement from the neutral position of “0” to the positive predetermined value) from the neutral position to the right ( That is, the target turning angle that gradually changes from “0” to a positive predetermined value) is stored, and the joystick 13 is displaced leftward from the neutral position (that is, from “0” to a negative predetermined value). The target turning angle that gradually changes from the neutral position to the left direction (that is, a negative predetermined value from “0”) is stored. However, in this case, the target of the steered wheel on the displacement side of the joystick 13 (the right steered wheel WHfr when the joystick 13 is displaced in the right direction and the left steered wheel WHfl when the joystick 13 is displaced in the left direction). The change in the turning angle is larger than the change in the turning wheel on the side opposite to the displacement side of the joystick 13, and the difference increases as the amount of displacement from the neutral position of the joystick 13 increases. Furthermore, the maximum value of the absolute value of the target turning angle in the contracted state is much larger than the maximum value of the absolute value of the target turning angle in the extended state described above. In addition, the characteristic curve of the turning angle described as the vehicle of FIG. 12 has shown the turning angle of the whole vehicle.

  Next, in step S74, the calculated target turning angle is output to the turning motor drive circuits 55a and 55b. The steered motor drive circuits 55a and 55b control the rotation of the electric motors 22a and 22b until the steered angle detected by the steered angle sensors 63a and 63b reaches the target steered angle. By the rotation of the electric motors 22a and 22b, the left and right steered wheels WHfl and WHfr are respectively steered to the target turning angle.

  After the process of step S74, a target rotational speed calculation process is executed in step S76. In this target rotational speed calculation process, the rotational speed table provided in the controller 50 is referred to calculate the target rotational speed according to the input signal representing the displacement position of the joystick 13 in the front-rear direction. As shown in FIG. 13, the rotation speed table stores a target rotation speed that increases proportionally with an increase in the amount of displacement in the front-rear direction around the neutral position of the joystick 13.

  Next, in step S78, a target rotation speed correction calculation process is executed. In this correction calculation, first, referring to a correction value table provided in the controller 50, a correction value corresponding to the input signal representing the left and right position of the joystick 13 is calculated. As shown in FIG. 14, in the correction value table, when the joystick 13 is in the neutral position in the left-right direction, both “1.0” are given as correction values for the left and right drive wheels WHrl, WHrr. Then, as the joystick 13 is displaced rightward from the neutral position, the correction value for the left drive wheel WHrl is proportional to the displacement amount until the displacement amount of the joystick 13 reaches the predetermined value (for example, “ 2.0 "), and when the displacement amount of the joystick 13 exceeds a predetermined value, it decreases to a predetermined value (for example," 1.0 ") according to the increase in the displacement amount, and is then maintained at the predetermined value. Further, as the joystick 13 is displaced leftward from the neutral position, the correction value for the left drive wheel WHrl is proportional to the displacement amount until the displacement amount of the joystick 13 reaches the predetermined value (for example, “ 0.0 ”), and when the amount of displacement of the joystick 13 exceeds a predetermined value, it decreases to a predetermined value (for example,“ −1.0 ”) with a larger slope according to the increase in the amount of displacement. Maintained at the value. The correction value for the right drive wheel WHrr changes symmetrically with the correction value for the left drive wheel WHrl.

  In step S78, the calculated correction values are multiplied by the target rotation speeds of the left and right drive wheels WHrl and WHrr calculated in step S76, respectively, to correct the target rotation speeds of the left and right drive wheels WHrl and WHrr. To do. In step S80, the corrected target rotation speed is output to the drive motor drive circuits 56a and 56b to instruct rotation control of the electric motors 32a and 32b. In step S82, the execution of this program is temporarily terminated. The drive motor drive circuits 56a and 56b feed back the rotational speeds of the left and right drive wheels WHrl and WHrr detected by the rotational speed sensors 65a and 65b, so that the electric motors 32a and 32b correspond to the calculated target rotational speed. Control to rotate forward or reverse at the rotation speed. In this case, when the rotational speed decreases during normal rotation and reverse rotation of the electric motors 32a and 32b, the drive motor drive circuits 56a and 56b perform regenerative braking control on the electric motors 32a and 32b, and the left and right drive wheels WHrl, WHrr is regeneratively braked. By such rotation control of the electric motors 32a and 32b, the left and right drive wheels WHrl and WHrr are rotated forward or reverse at a rotation speed corresponding to the target rotation speed. As a result, the vehicle moves forward and backward by operating the joystick 13 in the front-rear direction. At this time, if the steered wheels WHfl and WHfr are steered left and right by an operation in the left and right direction of the joystick 13, the vehicle turns left and right.

  The operation of the vehicle in the contracted state will be described in detail with reference to FIG. When the joystick 13 is operated in the front-rear direction while the left-right position of the joystick 13 is in the neutral position, the left and right drive wheels WHrl, WHrr rotate at the same rotational speed as shown in FIG. Since the left and right steered wheels WHfl and WHfr are not steered, the vehicle goes straight. In this case, if the joystick 13 is operated forward from the neutral position, the target rotational speed set in step S78 is set positive as shown in FIG. 13, and the vehicle moves forward. The forward speed increases as the amount of forward displacement of the joystick 13 increases. If the joystick 13 is operated backward from the neutral position, the target rotational speed set in step S78 is set negative as shown in FIG. 13, so that the vehicle moves backward. Then, the retreat speed becomes faster as the rearward displacement amount of the joystick 13 increases.

  When the joystick 13 is operated to the left from the neutral position, the target turning angle set in the step S72 is leftward as shown in FIG. 12, and both the left and right turning wheels WHfl and WHfr are leftward. The target turning angle of the steered wheel WHfl is larger than the target turning angle of the right turning angle WHfr. The target rotational speeds of the left and right drive wheels WHrl and WHrr set by the process in step S76 are the same as those in the above-described straight traveling, but the target rotational speed is corrected in step S78. As a result of this correction, as shown in FIG. 14, the absolute value of the target rotational speed of the left drive wheel WHrl becomes smaller than the absolute value of the target rotational speed of the right drive wheel WHrr. As a result, the vehicle turns left if it is in the forward state, and turns right (turns right backward) if it is in the backward state. In this case, as the joystick 13 is positioned to the left from the neutral position, the difference in turning angle between the left and right steered wheels WHfl and WHfr and the difference in rotational speed between the left and right drive wheels WHrl and WHrr increase. As shown in FIG. 16B, the vehicle approaches the vehicle side on the central axis connecting the left and right drive wheels WHrl and WHrr, and the vehicle can make a small turn. Note that the steered wheels Y indicated by broken lines in FIG. 16B indicate the influence of the steered wheels WHfl and WHfr on the vehicle as one steered wheel.

  Furthermore, when the joystick 13 is operated to the left, the target turning angle of the left steered wheel WHfl exceeds 90 degrees. The sign of the target rotational speed of the left drive wheel WHrl is opposite to the sign of the target rotational speed of the right drive wheel WHrr. That is, if the vehicle is in a forward traveling state (the joystick 13 is ahead of the neutral position), the target rotational speed of the left driving wheel WHrl is negative (corresponding to the rear), and the target rotational speed of the right driving wheel WHrr is positive ( Corresponding to progress). If the vehicle is in the reverse state (the joystick 13 is behind the neutral position), the target rotational speed of the left driving wheel WHrl becomes positive and the target rotational speed of the right driving wheel WHrr becomes negative. Accordingly, as shown in FIG. 16 (C), the left and right steered wheels WHfl and WHfr are steered in a “C” shape at the maximum and the left and right drive wheels WHrl and WHrr rotate in the opposite direction, so that the vehicle turns. The center X is a neutral position between the left and right drive wheels WHrl and WHrr as shown in FIG. As a result, the vehicle can turn in the left direction in the forward state and can turn in the right direction in the backward state.

  On the other hand, when the joystick 13 is operated rightward from the neutral position, the target turning angle is the right direction for both the left and right turning wheels WHfl and WHfr as shown in FIG. 12, and the target of the right turning angle WHfr is set. The turning angle is larger than the target turning angle of the left turning wheel WHfl. Then, the target rotational speed of the right drive wheel WHrr is smaller than the target rotational speed of the left drive wheel WHrl. As a result, the vehicle turns right if it is in the forward state and turns left if it is in the backward state. Also in this case, as the joystick 13 is positioned to the right from the neutral position, the turning angle difference between the left and right steered wheels WHfl and WHfr and the difference in rotation speed between the left and right drive wheels WHrl and WHrr increase. X approaches the vehicle side on the central axis connecting the left and right drive wheels WHrl, WHrr, and the vehicle can turn slightly.

  Furthermore, when the joystick 13 is operated to the right, the target turning angle of the right steered wheel WHfr exceeds 90 degrees. In this case, the sign of the target rotational speed of the right drive wheel WHrr is opposite to the sign of the target rotational speed of the left drive wheel WHrl. That is, if the vehicle is in a forward state, the target rotational speed of the right drive wheel WHrr becomes negative and the target rotational speed of the left drive wheel WHrl becomes positive. If the vehicle is in the reverse state, the target rotational speed of the right drive wheel WHrr becomes positive and the target rotational speed of the left drive wheel WHrl becomes negative. Therefore, also in this case, the left and right steered wheels WHfl and WHfr are steered in a “C” shape at the maximum, and the left and right drive wheels WHrl and WHrr rotate in the reverse direction, so the turning center X of the vehicle is the maximum The neutral position is between the left and right drive wheels WHrl and WHrr. As a result, the vehicle can turn in the right direction when in the forward state, and can turn in the left direction when in the backward state.

  As can be understood from the above operation description, according to the vehicle according to the above embodiment, the joystick 13 is operated to the front and rear and to the left and right in the extended state where the distance between the left and right steered wheels WHfl and WHfr and the left and right drive wheels WHrl and WHrr is long. As a result, the driving performance equivalent to that of a normal vehicle including the running stability can be obtained. Specifically, the left and right drive wheels WHrl and WHrr are torque-driven by an operation forward from the neutral position of the joystick 13. In this extended state, the left and right steered wheels WHfl and WHfr are given a mechanical braking force corresponding to the amount of operation by the operation from the neutral position of the joystick 13 to the rear, and the left and right drive wheels WHrl and WHrr are applied to the left and right drive wheels WHrl and WHrr. Since a braking force by regenerative braking by the electric motors 32a and 32b is applied, sufficient braking force is applied to the vehicle. Therefore, the vehicle in this extended state can travel on a general road or the like at a certain high speed to perform long-distance driving.

  In the contracted state where the distance between the left and right steered wheels WHfl and WHfr and the left and right drive wheels WHrl and WHrr is short, the left and right drive wheels WHrl and WHrr are controlled to move forward and backward by the operation of the joystick 13 in the front and rear direction. By this operation, it is possible to perform a small turning performance including on-site turning. Further, the rotational speeds of the left and right drive wheels WHrl and WHrr are controlled according to the amount of operation before and after the joystick 13, and at the time of deceleration, the braking force is applied to the vehicle only by regenerative braking of the electric motors 32a and 32b. This sudden deceleration of the vehicle can be avoided, and the position of the center of gravity of the vehicle becomes high and the occupant easily falls forward. Such a situation can be prevented in advance. Therefore, when the vehicle in this state is used like a wheelchair, high safety is ensured, and the vehicle can run safely and freely on the sidewalk and in the building.

  As described above, the vehicle can be operated by changing the mode between the extended state and the contracted state, so that a normal vehicle and a special vehicle such as a wheelchair can be used in one vehicle, which is convenient.

  Further, according to the vehicle according to the above embodiment, when the vehicle is switched to the extended state, the inclination angle of the vehicle body BD and the seat 11 with respect to the road surface is smaller than when the vehicle is switched to the contracted state. Therefore, when the vehicle is set in the extended state, the center of gravity of the vehicle and the occupant is lowered, so that the vehicle can travel stably. Moreover, by reducing the inclination angle of the vehicle body BD and the seat 11 in the extended state, it is possible to prevent the occupant from leaning forward during braking and performing acceleration control operation of the vehicle by forward operation of the joystick 13, This abnormal behavior of the vehicle can be avoided in advance. In the contracted state, the upper body of the occupant is raised, and driving operability is improved by using this vehicle like a wheelchair.

  Next, first and second modifications of the above embodiment will be described. As shown by a broken line in FIG. 5, the first modification includes an inclination angle sensor 81 that detects an inclination angle with respect to a road surface of the vehicle body BD assembled to the vehicle body BD. The tilt angle sensor 81 is connected to the controller 50. The controller 50 executes the program of FIG. 17 instead of the program of FIG. 6 in the above embodiment. Other configurations are the same as those in the above embodiment, and thus the description thereof is omitted.

  In the program of FIG. 17 according to the first modification, the determination process of step S90 is added between step S20 and step S22 of the program of FIG. 6 of the above embodiment. In step S90, the inclination angle from the inclination angle sensor 81 is input to determine whether or not the inclination angle of the vehicle body BD is normal when the vehicle is in the contraction control state. If the inclination angle of the vehicle body BD with respect to the road surface is normally controlled by the contraction state control in step S20, that is, if the vehicle body is set in the standing state, step S22 is performed based on the determination of “Yes” in step S90. The contraction state control routine is executed. However, if the inclination angle of the vehicle body BD with respect to the road surface is not normal, “No” is determined in step S90, and the process proceeds to step S16. Therefore, in this case, the vehicle is always set to the extended state without being set to the contracted state.

  According to the first modified example, the abnormal leaning of the vehicle body BD due to the contracted state of the vehicle in which the distance between the left and right steered wheels WHfl and WHfr and the left and right drive wheels WHrl and WHrr is short can be avoided, and the unstable state of the occupant can be avoided. At the same time, driving stability can be prioritized.

  Further, in this first modification, instead of the inclination angle sensor 81 detecting the inclination angle of the vehicle body BD with respect to the road surface, the inclination angle sensor 81 may detect the inclination angle of the seat 11 with respect to the road surface. . Also by this, the abnormal inclination of the vehicle body BD due to the contracted state of the vehicle can be avoided, the unstable state of the occupant can be avoided, and traveling stability can be prioritized. In particular, in this case, even when the seat 11 is tiltable with respect to the vehicle body BD, it can be dealt with. Furthermore, instead of the tilt angle sensor 81, the detection output of the angle sensor 61 may be used.

  The second modification includes an automatic changeover switch 82 and a navigation device 83 provided on the operation panel 12, as indicated by broken lines in FIG. The automatic changeover switch 82 instructs to switch automatically whether the vehicle is extended or contracted or selected by the occupant. The navigation device 83 is a well-known navigation device capable of detecting the position of the vehicle and guiding it to the destination, and has a function of detecting at least whether or not the vehicle is on the roadway. The automatic changeover switch 82 and the navigation device 83 are connected to the controller 50. The controller 50 executes the program of FIG. 18 instead of the program of FIG. 6 in the above embodiment. Other configurations are the same as those in the above embodiment, and thus the description thereof is omitted.

  In the program of FIG. 18 according to the second modification, steps S92 and S94 are added after step S12 of the program of FIG. 6 of the above embodiment. The process of step S92 is to determine whether or not the automatic changeover switch 82 is in an automatic changeover state between the extended state and the contracted state. When the automatic changeover state is not selected by the automatic changeover switch 82, “No” is determined in step S92, and the processing after step S14 similar to the above embodiment is executed. Thereby, in this case, the vehicle according to the second modification operates in the same manner as in the above embodiment.

  On the other hand, when the automatic switching state is selected by the automatic switching switch 82, “Yes” is determined in step S92, and a signal from the navigation device 83 is input in step S94, and this vehicle is on the roadway. Determine whether. If this vehicle is on the road, the vehicle is set to the extended state in step S16 based on the determination of “Yes” in step S94, and the extended state control routine of step S18 is executed. If this vehicle is not on the road, the vehicle is set in the contracted state in step S20 based on the determination of “No” in step S94, and the contracted state control routine in step S22 is executed. Therefore, according to the second modification, the vehicle is automatically set to the extended state or the contracted state in accordance with the environment in which the vehicle is located, and the occupant can perform driving suitable for the environment without performing many operations. The operation can be performed.

  Furthermore, in carrying out the present invention, the present invention is not limited to the above-described embodiments and modifications thereof, and various modifications can be made without departing from the object of the present invention.

  For example, in the above embodiment, the joystick 13 is used as the driving operation member, but a driving operation member other than the joystick 13 may be used. For example, you may use a wheel handle and an operation pedal like a general vehicle.

  Moreover, in the said embodiment, in order to calculate a target turning angle, a target drive torque, a target braking torque, a target rotation speed, and a correction value, the table previously provided in the controller 50 was utilized. However, instead of this, a function in which any one or more of the target turning angle, the target driving torque, the target braking torque, the target rotational speed, and the correction value is stored in advance in the controller 50 is defined. You may make it calculate using the function data to do. When using tables, it is common to calculate the target turning angle, target driving torque, target braking torque, target rotational speed, and correction value using interpolation calculation. Can be controlled without a sense of incongruity without using an interpolation calculation.

  In the above embodiment, the electric motors 32a and 32b are directly connected to the left and right drive wheels WHrl and WHrr. However, an electromagnetic clutch is provided between the electric motors 32a, 32b and the left and right drive wheels WHrl, WHrr, and a parking brake is provided for applying a mechanical braking force to the left and right drive wheels WHrl, WHrr. The left and right drive wheels WHrl and WHrr may be separated from the electric motors 32a and 32b by a clutch, and a parking brake force may be applied.

FIG. 1 is a schematic side view showing an extended state of a vehicle according to an embodiment of the present invention. FIG. 2 is a schematic side view showing a contracted state of the vehicle. FIG. 3 is a schematic perspective view showing an extended state of the vehicle. (A) is an enlarged side view of a steering apparatus, (B) is a top view in the casing of (A). It is a block diagram of the electric control apparatus of the said vehicle. It is a flowchart of the program performed by the controller of FIG. It is a flowchart which shows the detail of the expansion | extension state control routine of FIG. It is a flowchart which shows the detail of the contraction state control routine of FIG. It is a graph which shows the change characteristic of the target turning angle with respect to the left-right operation position of the joystick in the extended state. It is a graph which shows the change characteristic of the target drive torque with respect to the front operation position of a joystick in the expansion | extension state. It is a graph which shows the change characteristic of the target braking torque with respect to the back operation position of a joystick in the expansion | extension state. It is a graph which shows the change characteristic of the target turning angle with respect to the left-right operation position of a joystick in a contracted state. It is a graph which shows the change characteristic of the target rotation speed with respect to the front-back operation position of a joystick in a contracted state. It is a graph which shows the change characteristic of the correction value of the target rotation speed with respect to the left-right operation position of a joystick in a contracted state. (A) (B) is explanatory drawing for demonstrating the action | operation of the vehicle in the expansion | extension state. (A)-(C) are explanatory drawings for demonstrating the action | operation of the vehicle in a contracted state. It is a flowchart of the program performed by the controller of the vehicle which concerns on the 1st modification of the said embodiment. It is a flowchart of the program performed by the controller of the vehicle which concerns on the 2nd modification of the said embodiment.

Explanation of symbols

DESCRIPTION OF SYMBOLS 11 ... Seat, 13 ... Joystick, 14 ... Telescopic switch, 15 ... Reverse switch, 20a, 20b ... Steering device, 22a, 22b ... Electric motor, 32a, 32b ... Electric motor, 41 ... Screw rod, 42 ... Electric motor, DESCRIPTION OF SYMBOLS 50 ... Controller, 51 ... Front-rear position sensor, 52 ... Left-right position sensor, 53 ... Telescopic motor drive circuit, 54a, 54b ... Brake drive circuit, 55a, 55b ... Steering motor drive circuit, 56a, 56b ... Drive motor Drive circuit, 70a, 70b ... electromagnetic brake device, 81 ... tilt angle sensor, 83 ... navigation device, WHfl, WHfr ... left and right steered wheels, WHrl, WHrr ... left and right drive wheels

Claims (11)

A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
An extension mechanism capable of changing the distance between the pair of steered wheels and the pair of drive wheels;
When the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the expansion / contraction mechanism in conjunction with the change of the distance by the expansion / contraction mechanism , the operation control means is long. Compared to when switched to a state, the vehicle has a steering control means for allowing a turning angle of the pair of turning wheels according to an operation of the operation member to a large value. When the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the telescopic mechanism, the steered control means rotates the pair of steered wheels according to the operation of the operation member. The vehicle according to claim 1 , wherein a difference in steering angle between the pair of steered wheels is increased as a steering angle is increased. A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
An extension mechanism capable of changing the distance between the pair of steered wheels and the pair of drive wheels;
When the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state by the extension / contraction mechanism in conjunction with the change in distance by the extension / contraction mechanism , the operation control means Are driven in the same direction, and when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the telescopic mechanism, the pair of drive wheels are driven in the same direction and in opposite directions to each other. A vehicle characterized by having a drive control means capable of doing so. The drive control means is configured such that when the distance between the pair of steered wheels and the pair of drive wheels is switched to a short state by the telescopic mechanism, the pair of steered wheels is steered small when the pair of steered wheels is steered small. 4. The vehicle according to claim 3 , wherein the driving wheels are driven in the same direction and the pair of driving wheels are driven in opposite directions when the pair of steered wheels are largely steered. When the distance between the pair of steered wheels and the pair of drive wheels is short by the telescopic mechanism and the pair of drive wheels are driven in the same direction, the drive control means is The vehicle according to claim 4 , wherein a difference in rotational speed between the pair of drive wheels is increased as a turning angle of the pair of steered wheels according to the operation is increased. A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
An extension mechanism capable of changing the distance between the pair of steered wheels and the pair of drive wheels;
When the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state by the extension / contraction mechanism in conjunction with the change in distance by the extension / contraction mechanism , the operation control means and torque control, characterized in that it has a drive control means for speed controlling the pair of driving wheels when the distance between the pair of steered wheels and the pair of driving wheels by the expansion and contraction mechanism is switched to a short state And the vehicle. A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
An extension mechanism capable of changing the distance between the pair of steered wheels and the pair of drive wheels;
While providing a mechanical braking device for the pair of steered wheels, the pair of drive means is constituted by an electric motor,
When the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state by the expansion / contraction mechanism in conjunction with the change in distance by the expansion / contraction mechanism , the operation control means The mechanical braking device is actuated in response to the operation, and a braking force is applied to the pair of drive wheels by regenerative braking by the electric motor, and the pair of steered wheels and the pair of drives are driven by the telescopic mechanism. When the distance to the wheels is switched to a short state, the pair of driving wheels is controlled by regenerative braking by the electric motor in accordance with the operation of the driving operation member without operating the mechanical braking device. A vehicle having braking control means for applying power. The driving operation member is composed of a joystick capable of two-dimensional displacement,
The operation control means controls the driving of the pair of driving wheels according to the displacement of the joystick in the first direction, and the pair of the driving control means according to the displacement of the joystick in a second direction different from the first direction. The vehicle according to any one of claims 1 to 7 , which controls turning of the steered wheels. The first direction is the longitudinal direction of the vehicle;
When the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state by the telescopic mechanism, the operation control means is configured to respond to the forward displacement from the neutral position of the joystick. The rotation of the drive wheels is accelerated, the rotation of the pair of drive wheels is braked according to the displacement from the neutral position to the rear of the joystick, and the telescopic mechanism causes the pair of steered wheels and the pair of drive wheels to When the distance is switched to a short state, the pair of drive wheels are rotated forward according to the forward displacement from the neutral position of the joystick and the pair of the drive wheels according to the backward displacement from the neutral position of the joystick. 9. The vehicle according to claim 8 , further comprising drive direction control means for rotating the drive wheel backward. A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
The distance between the pair of steered wheels and the pair of drive wheels can be changed, and when the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state, the distance is short. An expansion / contraction mechanism that reduces the angle of inclination of the seat on which the occupant is seated with respect to the road surface,
An inclination angle sensor for detecting an inclination angle of the seat with respect to a road surface;
When the distance between the pair of steered wheels and the pair of drive wheels is instructed to be in a short state, the telescopic mechanism is provided on condition that the tilt angle detected by the tilt angle sensor is abnormal. A vehicle having forcible control means for controlling and forcibly controlling the distance between the pair of steered wheels and the pair of drive wheels to be long. A pair of turning means for independently turning a pair of left and right turning wheels;
A pair of drive means for independently driving the pair of left and right drive wheels;
A driving operation member for driving the vehicle;
The pair of steering means and the pair of drive means are controlled in accordance with the operation state of the driving operation member to steer the pair of steered wheels and drive control means to drive the pair of drive wheels. In the vehicle
The distance between the pair of steered wheels and the pair of drive wheels can be changed, and when the distance between the pair of steered wheels and the pair of drive wheels is switched to a long state, the distance is short. An expansion / contraction mechanism that reduces the inclination angle with respect to the road surface of the vehicle body, compared to when switched to
An inclination angle sensor for detecting an inclination angle with respect to a road surface of the vehicle body;
When the distance between the pair of steered wheels and the pair of drive wheels is instructed to be in a short state, the telescopic mechanism is provided on condition that the tilt angle detected by the tilt angle sensor is abnormal. A vehicle having forcible control means for controlling and forcibly controlling the distance between the pair of steered wheels and the pair of drive wheels to be long.

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