Abstract: A steer angle control system for a controlled vehicle comprises sensors for sensing the steering wheel angle and the vehicle speed of the controlled vehicle, a processor such as a microcomputer, and an actuator for steering the front and/or rear wheels of the controlled vehicle in response to a control signal produced by the processor. The processor includes a reference behavior determining section for determining the value of a reference output motion variable corresponding to the sensed steering wheel angle and vehicle speed by solving a reference mathematical model representing desired vehicle motion characteristics, a vehicle behavior monitoring section for determining a value of the plant output motion variable which is a linear combination of a yawing motion variable, such as a yaw rate of the controlled vehicle, and a side translational motion variable, such as a lateral acceleration of the controlled vehicle, and a controller section for producing the control signal representing a target steer angle so as to reduce an error between the reference variable and the plant variable.

Abstract: A control system for controlling a driving torque distribution between front and rear axles of a four wheel drive vehicle includes a transfer clutch capable of continuously varying a torque transmitted to the front axle, front and rear wheel speed sensors for determining a front and rear wheel speed difference, a sensor for directly or indirectly sensing a lateral acceleration of the vehicle and a control unit. The control unit controls the transfer clutch in a characteristic such that the torque transmitted to the front axle is increased continuously and monotonically with an increase of the wheel speed difference at a steep rate when the lateral acceleration is low, and at a gradual rate when the lateral acceleration is high.

Abstract: A camber control system varies the camber of a wheel of a motor vehicle. The camber control system includes a detector for detecting a direction in which front wheels are steered, a controller for producing a control signal in response to a signal produced by the detector, an actuator operable in response to the control signal from the controller, and a rear wheel camber varying mechanism actuatable by the actuator for varying the camber of rear wheels. The controller is arranged such that the control signal produced thereby enables the actuator to operate the rear wheel camber varying mechanism so that the camber of outer and inner rear wheels with respect to a motor vehicle turning direction corresponding to the direction in which the front wheels are steered, is rendered negative and positive, respectively. The rear wheel camber varying mechanism has a wheel supporting member for supporting a rear wheel rotatably thereon, and lower and upper coupling members interconnecting the wheel supporting member and a body of the motor vehicle. The upper coupling member is movable transversely of the motor vehicle body, and the actuator is coupled to a portion of the upper coupling member which is mounted on the motor vehicle body.

Abstract: A control system for a power steering apparatus having a steering wheel angle detection device comprising a steering angle sensor for generating reference pulses at a plurality of steering wheel angle positions, including a neutral position of a steering wheel, and generating angle pulses as the steering wheel is rotated, an up/down counter for counting up or down the angle pulses supplied from the steering angle sensor depending on the direction of rotation of the steering wheel, and a vehicle velocity sensor for detecting the vehicle velocity. When the vehicle velocity detected by the vehicle velocity sensor is higher than a predetermined velocity and a reference pulse is detected by the steering angle sensor which is determined to be a steering wheel straight ahead position then the up/down counter is reset to zero.

Abstract: An accurate and high-speed measurement of the vehicle wheel alignment is achieved by an optoelectronic, non-contact measurement system. This system includes photoelectric sensors for detecting the distance between a reference vertical plane and a tire side surface of each wheel, and a stepping motor for adjusting the position of the sensors to follow-up the displacement of the wheel in a direction parallel to the longitudinal axis of the vehicle. Operation of the stepping motor is controlled by a microcomputer on the basis of the updated distance data delivered from the sensor inputs. The microcomputer processes the input data to compute a toe-in or a camber of the wheel for the analog or digital display.

Abstract: A rear suspension system for automobiles, comprising: a trailing arm pivoted to the automobile body at its front end and to a knuckle at its rear end; a first and a second lateral links extending laterally across an upper portion and a lower portion of the knuckle and the corresponding locations of the automobile body, respectively; and a third lateral link extending laterally across an intermediate position of the knuckle, located between the upper portion and the lower portion of the knuckle and behind a central axial line of a wheel axle of the knuckle, and the corresponding location of the automobile body. The second lateral link has a substantially same length as the third lateral link. Thus, the mounting positions of the lower end of the shock absorber can be lowered, and the resistance against the changes in the toe angle and the camber angle is increased. If the first lateral link is shorter than the second lateral link, the camber angle of the outer wheel of a vehicle making a turn can become negative so as to improve the cornering limit of the automobile.

Abstract: A personal mobility vehicle includes a main frame unit with front and back ends, both with wheels thereon, a steerable front wheel, an operator's seat and vehicle controls. A pair of spaced rear wheels are mounted at the back end of the vehicle and include moveably mounted axles supporting the rear wheels and connected to arms with mechanisms for selectively angularly moving the axles outwardly and inwardly of the main frame unit to vary wheel base and wheel track. A motor is connected to the wheel support structure for remotely varying the wheel base and wheel track. A separate drive motor is operatively connected to the wheels for movement of the vehicle.

Abstract: Proposed in accordance with the invention is a method of measuring the camber, KPI and caster wheel alignment angles in the front axle and suspension assembly of a motor vehicle without the need for recourse to a levelled surface or to any gravitation­-sensing instruments for the purpose of the measurements. One front wheel at a time is measured, for which purpose the wheel is fitted with a projecting pin parallel to the wheel axle intended to support a laser beam machine which emits a beam perpendicular to the wheel axle. A screen marked with reference lines is positioned at a certain distance away from the wheel, initially in front of, and then alongside the wheel, with the direction of the reference lines corresponding to the direction of the reference plane of the vehicle. By causing the laser to rotate about the pin, and by causing the wheel to execute steering movements with the laser fixed to the pin, the laser beam can be made to "draw" lines on the screen, which lines produce angles with the reference lines of the screen in accordance with the camber, KPI and caster angles of the wheel. In order to be able to carry out the measurements rapidly and accurately, and at the same time to have the results of measurement recorded, the use of a special design of the aforementioned screen is proposed, more specifically in the form of a measurement panel (60) equipped with a pointer (80), to which panel a sheet of paper bearing a scale (90) can be secured. The results of measurement are recorded on this automatically by the operator making a mark with a pen in an opening (81) in the pointer (82) after every measurement adjustment.

Abstract: A control system for steering front wheels or rear wheels of a controlled vehicle has a processing unit such as a microcomputer which determines a desired value of a dynamical variable such as yaw acceleration corresponding to sensed steering wheel angle and sensed vehicle speed by solving equations of motion of a vehicle in which parameters are set equal to desired values determined by a desired vehicle. From the desired value of the dynamical variable, the processing unit determines a desired value of a steering angle of the front or rear wheels, and commands a hydraulic actuator to steer the front or rear wheels so that the controlled vehicle behaves as if it were the desired vehicle. The controlled vehicle may have a mechanical steering linkage for steering the front wheels in a conventional manner, and the control system may be arranged to control the steering angle of the rear wheels.

Abstract: A vehicle rear suspension system including a wheel hub (15) supporting a rear wheel (3) for rotation, a front lateral link (4) extending transversely and connected through a front inner rubber bush (8) with the vehicle body (8) and through a front outer rubber bush (12) with the wheel hub, a rear lateral link (5) extending transversely and connected through a rear inner rubber bush (10) with the vehicle body and through a rear outer rubber bush (14) with the wheel hub. The rubber bushes have resiliencies such that deflections are produced under a transversely inwardly directed side force applied to the wheel from a road on which the wheel is running to produce a change in a toe direction of the wheel in a manner that the toe direction is changed with respect to an increase in the side force with a first rate under a first range of the side force, with a second rate which is smaller in a sense of toe-in direction than the first rate under a second range of the side force which is larger than the first range and with a third rate which is larger in a sense of toe-in direction than the second rate under a third range of the side force which is larger than the second range.

Abstract: A front wheel supporting member comprises a steering handle, a member supporting a single front wheel, an arm which supports the front wheel supporting member on a motor vehicle body, and a link assembly by which the steering handle and the front wheel supporting member are angularly movable coupled to each other. The link assembly includes a first universal joint operatively coupled to the steering handle and a second universal joint operatively coupled to the front wheel supporting member. The second universal joint has a center on the axis of angular movement of the front wheel supporting member.

Abstract: PURPOSE:To improve assembly workability of a sensor, by a method wherein the electric motor, rocking and displacing a lever on the rear wheel side, of a rear wheel steering ratio varying mechanism is disposed on the same axis as the rotary axis of a rotary body and on the car body side, and a front wheel steering angle sensor is situated to a part of the motor. CONSTITUTION:A rear wheel steering ratio varying mechanism 1 located to a transmission rod system 5 to transmit the steering motion of a font wheel 10 to the rear wheel 14 side is provided with a rotary body 3 rotatably supported on a vertical axis Z to a bracket 2. An arm 4 pivotally mounted to a rod 5a on the front wheel side is extended sideways (in a direction Y) from the body 3, and a lever 7 pivotally mounted to a rod 5b on the rear wheel side is rotatably supported on an axis X crossing the axis Z at right angles. An electric motor 6 is mounted in order to rotate the lever 7 on the axis X, but in this case, the motor 6 is situated on the same axis as the axis Z, and a front wheel steering angle sensor 29a to detect a steering amount of front wheels 10 with the aid of the motor 6 is mounted to a protection cover 30 of the motor 6.

Abstract: A rear wheel steering control system for a four wheel steerable vehicle has a controller such as a microcomputer for steering rear wheels through a hydraulic actuator. When a small turning radius is required, the controller steers the rear wheels in an opposite direction to a direction in which the front wheels are steered. The control system further has various sensors such as front wheel angle sensor, rear wheel angle sensor, vehicle speed sensor and gear position sensor for sensing a position of a transmission. From one or more of the sensor output signals, the controller determines whether the vehicle is in a predetermined condition in which the rear wheel steering action in the opposite direction should be restrained in order to prevent the rear end of the vehicle from swinging laterally in the opposite direction and bumping against an adjacent object. If it is determined that the vehicle is in the predetermined condition, the controller steers the rear wheels gradually in the opposite direction.

Abstract: An automotive vehicle having a fluid-operated, four wheel steering system for steering not only the front wheel pair, but also the rear wheel pair as a function of the amount of turn of the front wheel pair with respect to the direction of straightforward run of the vehicle. The system makes use of a front cylinder operatively associated with a steering gear assembly and a rear cylinder operated by a fluid medium supplied from the front cylinder for steering the rear wheel pair. In order for the steering system to be responsive to the vehicle running speed thereby to control the amount of turn of the rear wheel pair appropriate for a particular range of vehicle running speed, a device is provided for accommodating a portion of the fluid medium to be supplied to the rear cylinder when the pressure of the fluid medium increases to a value higher than a predetermined pressure. Increase of the fluid pressure over the predetermined value takes place when the steering wheel is turned during the low speed run of the vehicle.

Abstract: A vehicle four wheel steering system including a front wheel steering mechanism for steering the front wheels in response to an operation of a manually operated steering member, a rear wheel steering mechanism for steering rear wheels in response to a steering movement of the front wheel. A control unit is provided for changing the steering ratio of the rear wheel steering angle to the front wheel steering angle in accordance with the vehicle speed. The steering ratio is further modified so that the rear wheel steering angle is added with a modification angle in the direction opposite to the direction of steering of the front wheel, the modification angle being increased in response to an increase in the side force on the vehicle.

Abstract: A four wheel steering system for non-articulated vehicles including a digital angle register for periodically generating front wheel angle information θ F1 , θ F2 . . . θ FN representing the incremental angular positions of the front wheels and a rear wheel angle generator for storing the information and utilizing it after a delay distance D to control the angular positions θ R1 , θ R2 . . . θ RN of the rear wheels.

Abstract: This invention provides an apparatus for controlling the steering angle of a rear wheel in which a vehicle speed and a steering angle of a front wheel are detected and a rear wheel is controlled to toe-in in response to the vehicle speed and steering angle of the front wheel during high speed turning. Turning stability and control during high speed turning is improved.

Abstract: In a rear wheel steering device for a front and rear wheel steering system of a wheeled vehicle wherein rear wheels are steered by displacement of tie rods connected to the knuckles of the rear wheels and disposed in the lateral direction of the vehicle in an opposite phase relationship relative to the front wheels at least under a certain condition such as a small steering angle or a low vehicle speed, the centers of the turning radii of the rear wheels are made to coincide with each other by determining the geometry of the tie rods and the knuckle arms in such a manner that a pair of imaginary lines formed by connecting the pivot points between the knuckle arms and the tie rods to the points of intersection between a horizontal plane containing the said pivot points and the center lines of rotation of the knuckles relative to the vehicle body intersect at a point which is located ahead of the center line of the rear wheel axle. As a result, the slip angle of the rear wheels is minimized, particularly when the steering angle is great.

Abstract: A four wheel drive vehicle comprising dirigible front wheels and nondirigible rear wheels. Drive of an engine is transmitted to the front and rear wheels through a propelling drive transmission for producing at least two, high and low, speeds, a front wheel change speed mechanism, and a rear wheel change speed mechanism. The front and rear wheel change speed mechanisms are controlled by a control device to produce a high speed state with the front wheels accelerated when a steering angle of the front wheels exceeds a predetermined angle and the propelling drive transmission is in a low speed position, to produce a low speed state with the front wheels accelerated when the steering angle of the front wheels exceeds the predetermined angle and the propelling drive transmission is in a high speed position, and to produce a standard state in which the front and rear wheels are driven at the same speed when the steering angle of the front wheels is below the predetermined angle.

Abstract: A "short turn" powered vehicle having a transverse structural mower housing or implement that is used to also vertically stablize the unit. One embodiment uses a self powered mower housing with lateral support wheels which also give lateral support, as do the choice of implements, by means of a vertically restricting hinge in relation to a powered drive wheel; thus the drive wheel is in a floating mode as it gives thurst to the housing or implement, so as to always have traction on uneven ground. On each of the embodiments steering is done by, either a generally centrally located steered front support wheel steered from a rearward operator's seat on the vehicle, or steering being from an operator's seat rearward on the vehicle, by breaking of either of the housing's or implement's lateral support wheels and there being at least one castor type front support wheel or lateral front support wheels located close to the rear support wheels. Or by hand mower type handles mounted on the rear of the vehicle drive wheel frame, without the operators seat, but with at least one front caster type support wheel. In each of the steering modes, except the one, steering is done by the thurst of the rear drive wheel around one of the laterial housing or implement's support wheels. The vehicle is vertially stabilized by the vertically restricted pivoting hinge with a rear drive wheel that is in a floating mode in relation to the housing or implement.

Abstract: An apparatus for steering the front and rear wheels of a motor vehicle includes a detector for detecting an effect of operation by a driver of the motor vehicle on the behavior of the motor vehicle, and a rear wheel steering control device for returning the rear wheels to a neutral steering position when a rate of change of a detected output from said detecting means is in excess of a prescribed value. The apparatus may further include another control device for variably controlling the ratio of a rear wheel steering angle to a front wheel steering angle according to a speed of the motor vehicle. The detector comprises a steering angle sensor for detecting a steering angle of the front wheels or a speed sensor for detecting the speed of travel of the motor vehicle. The rate of change of the detected output is calculated by said rear wheel steering control device from time-series steering angle data or speed data produced from information generated by said steering angle or speed sensor. The prescribed value to be compared with the rate of change of the steering angle output is substantially the same as a maximum rate of change of a steering angle which can be produced during steering operation of the motor vehicle. The prescribed value to be compared with the rate of change of the speed output is substantially the same as a maximum rate of change of a speed of the motor vehicle which can be produced upon deceleration of the motor vehicle.

Abstract: A four-wheel steering system in a wheeled vehicle the front wheel steering mechanism (10) of which is drivingly interconnected to a rear wheel steering mechanism to steer the rear road wheels (WR) in either the same or the opposite direction as the front road wheels (WF) in dependence upon the turn-angle of the steering wheel (WS) of the vehicle. In the steering system, the rear wheel steering mechanism includes an operation rod (30) operatively connected at the opposite ends thereof to the rear road wheels (WR), and a connecting mechanism (A) is assembled in combination with the rear wheel steering mechanism for effecting axial displacement of the operation rod (30) in response to operation of the front wheel steering mechanism (10) and for controlling the displacement direction of the operation rod (30) in dependence upon the turn-angle of the steering wheel.

Abstract: A front wheel steering device comprises a steering handle (1), a member (17) supporting a single front wheel (3), an arm (19/21) which supports the front wheel supporting member (17) on a motor vehicle body (5), and a link assembly (43) by which the steering handle (1) and the front wheel supporting member (17) are angularly movably coupled to each other. The link assembly (43) includes a first universal joint (53) operatively coupled to the steering handle (1) and a second universal joint (59) operatively coupled to the front wheel supporting member (17). The second universal joint (59) has a center (02) on the axis (K) of the angular movement of the front wheel supporting member (17).

Abstract: Disclosed is a rear wheel suspension device for a front and rear wheel steering vehicle wherein rear wheels are steered in an opposite phase relationship relative to the front wheels at least under a certain condition. The structure of the suspension for the rear wheels is so determined that a caster angle of each of the rear wheels relatively sharply increases as the distance between the vehicle body and the rear wheel is increased from a neutral state and maintains a smaller positive value as the distance between the vehicle body and the rear wheel is decreased from the neutral state. This can be accomplished by pivotably connecting the knuckle for each of the rear wheels by an upper arm and a lower arm to the vehicle body, respectively, and a rotational axial line of the upper arm inclines downward at its forward portion while the rotational axial line of the lower arm extends substantially parallel to the length of the vehicle. Preferably, the rotational axial line of the upper arm additionally inclines inward at its forward portion. Thus, the force required to maintain a certain steering angle changes smoothly as the steering angle is increased and at the same time the tendency of the rear wheels to take a straight course is maintained.

Abstract: PURPOSE:To obtain the superior traveling performance over the whole speed range by providing a rear-wheel suspension means equipped with a driving mechanism for varying the toe angle of the rear wheel and operation-controlling the driving mechanism according to the car speed data. CONSTITUTION:A rear wheel suspension means 1 in dual link strat system is equipped with front and rear arms 3 and 4 in pairs, and the basic edge of the front arm 3 is supported onto a body-side bracket 6, and the rear arm 4 is arranged in slidable ways. The rear arm 4 is connected to a screw cylinder 8 through a ball joint 7, and said screw cylinder 8 is screwed with the screw part 10 in the mutual reverse screw form at the both edges of a driving shaft 9. Said driving shaft 9 is revolved through a deceleration gear train 11 by the operation of a control motor 12, and said control motor 12 is controlled by a controller 15 so that the toe angle theta of the rear wheel 2 becomes zero, when the car speed detected by a car speed sensor 16 is a prescribed value (e.g., 60km/h) or less, and the toe angle theta increases on the toe-in side when the car speed is over the prescribed value.

Abstract: A steering system for a vehicle having a steering wheel, steerable front wheels and steerable rear wheels. The system comprises a linkage arrangement operatively interconnecting the steering wheel with the front and rear wheels for steering the front and rear wheels in response to operation of the steering wheel. The linkage arrangement includes a mechanical linkage mechanically connected with the steering wheel so as to transmit steering effort. The mechanical linkage is provided with a restoring mechanism for exerting restoring force to said mechanical linkage so as to urge the steering wheel toward a neutral position thereof. Favorable returnability of the steering system is achieved in this arrangement.

Abstract: An optical toe/track measurement system includes a pair of toe gauge assemblies respectively mountable on the two wheels at one end of a motor vehicle and a pair of track scale assemblies respectively mountable on the other two wheels of the vehicle. Each toe gauge assembly includes an elongated tubular housing having toe and track projection systems for respectively projecting toe and track light beams from the opposite ends of the housing, the track beam being projected coaxially with the housing onto the track scale on the same side of the vehicle, while the toe beam is projected perpendicular to the longitudinal axis of the housing onto a scale carried by the toe gauge assembly on the other side of the vehicle. Light is supplied respectively to the two toe gauge assemblies throught two fiber optic cables from a single remote light source. Each fiber optic cable has an input end which plugs into a receptacle in the source enclosure and a bifurcated output end which is optically coupled to both of the projection systems in the associated toe gauge assembly.

Abstract: PURPOSE:To improve the turn-traveling stability and reduce the abrasion of a tire and improve fuel consumption by increasing the toe-in quantity of a rear wheel when a front wheel steering angle is over a prescribed value CONSTITUTION:The front-wheel steering angle is detected by the turning angle sensor 60 of a steering column 58 and input into a microcomputer 50 Said microcomputer 50 determines the toe-in quantity on the basis of the signals of the turning angle sensor 60 and a brake power detecting unit 64, and controls the toe-in quantity of the rear wheels by operating the solenoid valves 40 and 46 through a driving circuit 66 If the front wheel steering angle 60 is over a prescribed value at this time, the toe-in quantity is increased With such constitution, the traveling stability in turn is improved, and the abrasion of a tire is reduced, and fuel consumption is improved