Abstract: A vehicle attachment for guiding a vehicle includes a magnetic tape sensor, at least one sensor, a controller, at least one coupling device for attachment to the vehicle, and a vehicle interface system. The magnetic tape sensor is configured to detect a path. The at least one sensor can detect whether there are any obstructions along the path. The controller is configured to steer the vehicle along the predefined path and to adjust the speed of the vehicle to avoid coming in contact with any obstructions. The vehicle interface system is configured to communicatively couple the controller to at least one electronic control unit of the vehicle.

Abstract: A control system of a self-driving tractor can access sensor data to determine a set of trailer configuration parameters of a cargo trailer coupled to the self-driving tractor. Based on the set of trailer configuration parameters, the control system can configure a motion planning model for autonomously controlling the acceleration, braking, and steering systems of the tractor.

Abstract: A wheeled work vehicle (1) comprises a forward chassis part (4) and a rearward chassis part (5) pivotally connected about a substantially vertically extending primary pivot axis (7) for steering thereof. A pair of forward ground engaging wheels (29) are carried on a forward suspension unit (32), and a pair of rearward ground engaging wheels (30) are carried on a rearward suspension unit (33). The forward suspension unit (32) is pivotally connected to the forward chassis part (4) by a pair of main forward transverse pivot shafts (63) pivotally coupled to the forward chassis part (4) by corresponding main forward pivot mountings (65). The main forward transverse pivot shafts (63) defines a main forward transverse pivot axis (59) about which the forward suspension unit (32) is pivotal relative to the forward chassis part (4).

Abstract: An automatic air suspension control system is provided for use in combination with a vehicle having a non-driven rear axle, a driven rear axle, and an air suspension associated with the rear axles to apply a load to each of the rear axles. The air suspension control system is programmed to maintain the load applied to the non-driven rear axle at a level that is less than the load applied to the driven rear axle until the load applied to the driven rear axle is equal to a threshold amount. The threshold amount may be equal to the maximum load that may be legally applied to the driven rear axle or some lower level. There may be no load applied to the non-driven rear axle prior to the load on the driven rear axle reaching the threshold amount or may be a non-zero amount.

Abstract: A hydraulic system includes a hydraulic pump. A first hydraulic shock is coupled to a first port of the hydraulic pump. A second hydraulic shock is coupled to a second port of the hydraulic pump. A first hydraulic cylinder is coupled to the first port of the hydraulic pump. A second hydraulic cylinder is coupled to the second port of the hydraulic pump. A first valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. The first valve can be actuated by a computer system or can be a ball and spring check valve. A second valve is coupled between the first hydraulic cylinder and second hydraulic cylinder. A flow direction of the second valve is opposite a flow direction of the first valve. A first piston is disposed in the first hydraulic cylinder, and a second piston is disposed in the second hydraulic cylinder.

Abstract: An electronic device and a method for determining whether a vehicle suspension system has degraded by positioning the electronic device in a vehicle includes activating a camera to initiate data capture within the electronic device. The camera is positioned to capture a change in a field of view during vehicle operation. The method includes calculating a vehicle suspension operating characteristic based on information captured by the camera and determining whether the calculated vehicle suspension operating characteristic exceeds a threshold. A signal indicative of suspension degradation is output when the threshold is exceeded.

Abstract: The disclosure relates to a ride height adjustment system useful for self-adjusting casters on suspension systems of harvesters, such as self-propelled windrowers. The suspension system utilizes sensors and hydraulic actuators operably linked to each caster, the hydraulic actuators responding to a detected ride height of the harvester to adjust the position of the casters to achieve the preferred ride height.

Abstract: A disclosed lift axle is suitable for a vehicle that has a first wheel for supporting the vehicle on a road surface. The lift axle system includes a lift mechanism that is coupled to the vehicle and is configured to reciprocate an axle between a stowed position and deployed position. The lift axle system further includes a second wheel coupled to the axle. The second wheel engages the road surface when the lift mechanism is in the deployed position, and the second wheel is disengaged from the road surface when the lift mechanism is in the stowed position. The second wheel has a lower rolling resistance than the first wheel.

Abstract: A dynamic weight shift suspension system for shifting the tandem axle loads on a vehicle. The system includes a first airbag connected between the drive axle of a tandem and the vehicle frame, and a second airbag connected between a tag axle of a tandem and the vehicle frame. The system also has a mechatronic control unit comprising at least one port and at least one solenoid. The mechatronic control unit is in direct fluid communication with the airbags and an air supply via fluid communication lines.

Abstract: A vehicle suspension system having a twist beam axle including a crossbeam and two trailing arms connected thereto. The rear ends of each trailing arm, in the motor vehicle longitudinal direction, having with a wheel mount for fastening a motor vehicle wheel. The front ends of each trailing arm connected via a bearing to the motor vehicle body. Each bearing associated with a MEMS designed as an actuator wherein movements of the bearings and therefore the twist beam axle about the vertical motor vehicle axis can be caused or unfavorable movements of the twist beam axle can be counteracted.

Abstract: A mechanical down-stop for heavy-duty vehicle axle/suspension systems which includes an angled bracket that is rigidly/stiffly attached to the vehicle frame at one end, and is attached to a flexible portion of the mechanical down-stop at its other end. The flexible portion is attached to a beam of the axle/suspension system. The angled bracket is formed of an elastically deformable material and includes a bend that enables the bracket to act as a spring. The angled bracket and the flexible portion limit downward movement and react the downward force of the beam.

Abstract: An apparatus is provided for raising and lowering a vehicle that is supported by a wheel suspended from a frame of the vehicle by a suspension component. The apparatus includes a linear actuator that is vertically oriented to move the wheel of the vehicle relative to the frame of the vehicle. A compression device is arranged to compress the suspension component of the vehicle in response to movement of the wheel by the linear actuator.

Abstract: A base unit for a vehicle such as a mobile work platform includes a chassis and multiple wheels, at least one of the wheels being mounted on the chassis by a suspension mechanism including a suspension element. The suspension element pivots relative to the chassis about a substantially horizontal pivot axis between an upper position and a lower position, and a stop member engages the suspension element in the upper position to limit its upwards movement. A biasing mechanism exerts a biasing force on the suspension element to urge the suspension element upwards towards the upper position.

Abstract: A walking beam assembly includes a support beam and a mount member configured to mount the support beam on a vehicle chassis. Furthermore, the assembly includes a gear assembly that is supported proximate an end of the support beam. The gear assembly includes a gear train and a gear housing. The gear train is operably coupled to a wheel hub. The gear housing substantially encloses the gear train. Moreover, the walking beam assembly includes an input drive assembly with at least one movable part configured to deliver an input torque from the vehicle engine to the gear train. The input drive assembly includes an input drive housing that substantially encloses the at least one movable part. The input drive housing is attached to the gear housing such that an interior of the input drive housing is in fluid communication an interior of the gear housing.

Abstract: In a truck vehicle, a controller controls a mechanism to apportion the sum total of weight borne by a tandem axle between a drive axle and a tag axle.

Abstract: The invention relates to a powered wheelchair for transporting a person, comprising a seat frame for supporting the person, a pair of opposing main wheel assemblies, including a first main wheel assembly and a second main wheel assembly connected to the seat frame, and a third main wheel assembly arranged spaced apart from the pair of opposing main wheel assemblies and connected to said seat frame. The powered wheelchair further comprises a support wheel arrangement for supporting the powered wheelchair, said support wheel arrangement having a main beam and a front support wheel unit capable of being applied to a ground surface. The main beam is rotatably connected to said third main wheel assembly at a third connection point and connected via a guiding mechanism to the first main wheel assembly at a first connection point.

Abstract: A trailing axle suspension system is disclosed comprising an auxiliary chassis, an axle suspension system suspending a trailing axle from the auxiliary chassis, and an auxiliary chassis system suspending the auxiliary chassis from the chassis of a motor vehicle. With the auxiliary chassis suspension system including a pair of suspension arms supporting the auxiliary chassis for pivotal movement and adapted to be pivotally connected to the motor vehicle chassis. And with the axle suspension system and auxiliary chassis suspension system adapted to cooperatively establish the auxiliary chassis and trailing axle in a stowed condition on the motor vehicle and establish the auxiliary chassis and trailing axle in a deployed condition at a location rearward of the motor vehicle chassis and then forcibly cause the auxiliary chassis to help support the motor vehicle chassis with the trailing axle.

Abstract: A lift axle suspension for a tandem trailer has first and second suspension air bags for first and second axles. There is a lift air bag that, when pressurized, applies a lifting force to lift the second axle relative to the first axle. A first pneumatic circuit supplies compressed air to the first suspension air bag and a diverter valve and is controlled by a height selector valve that is opened and closed based on the ride height of the trailer. The diverter valve selectively supplies compressed air to the second suspension air bag and a pressure regulator that limits air pressure to a predetermined pressure. A second pneumatic supplies compressed air to the lift air bag and is controlled by a pilot valve.

Abstract: An automatic auxiliary axle control system is disclosed for a load-transporting motor vehicle having two or more primary axles and one or more auxiliary axles wherein the control system detects a noncompliant axle carrying weight condition when the weight of the vehicle acting on any one of the primary axles exceeds a prescribed maximum allowable axle carrying weight assigned to that axle and also when the weight acting on any group of the axles arranged consecutively exceeds a prescribed maximum allowable axle group carrying weight assigned to that axle group. And the control system on such detection effects auxiliary axle usage that results in no maximum allowable axle carrying weight and maximum allowable axle group carrying weight being exceeded provided the current gross vehicle weight does not exceed a prescribed maximum allowable gross vehicle weight determined by all of the axles and the current center of gravity of the vehicle is located within a certain compliance-manageable range.

Abstract: A tag axle suspension system can include a tire and at least one hanger bracket pivotable relative to a vehicle frame to deployed and lifted configurations. In the lifted configuration, the tire can be a lowest component of the suspension system, and can be a first component to engage a road surface. A tag axle suspension system can include an air spring and a travel limit device that limits compression of the air spring in a lifted configuration of a hanger bracket. A tag axle suspension system can include an axle, a suspension arm pivotably connected between a hanger bracket and the axle, and a travel limit device that limits displacement of the suspension arm in a lifted configuration of the hanger bracket. The travel limit device can limit displacement of the axle toward an air spring support in the lifted configuration of the hanger bracket.

Abstract: A simply structured suspension structure for an electric wheelchair includes a frame, two drive units, two front guide units, two front shock absorbers, two anti-roll units, and two rear shock absorbers. The two front guide units are located at both sides of the frame and each include a front guide wheel, a front suspension arm and a torsion spring. The two front and rear shock absorbers are connected to the frame. The two anti-roll units are located at both sides of the frame. When the front guide arms drive the front guide wheels to pivot, the torsion springs can produce a reaction force to prevent the frame from rolling over, improving safety. When the suspension structure runs across an uneven bumpy road, the front and rear shock absorbers can ease the shock imposed on the frame, enhancing sitting comfort.

Abstract: The present disclosure relates to double acting suspension axle assemblies that can be used to facilitate mobility of a heavy load transporter and/or to adjust a deck height of the heavy load transporter. Each axle assembly includes a wheel assembly and a double-acting hydraulic cylinder. The double acting suspension axle provides the ability to force the hydraulic cylinder of each axle assembly to fully retract without relying solely on gravity. The double acting suspension axle assembly may be incorporated directly into or permanently affixed to other large structures, such as mobile robots, large tooling structures, gantry cranes, or other large machinery to provide the precise control of mobility and forced lowering capabilities.

Abstract: A lift axle suspension system is provided with a frame bracket member connectable to a vehicle frame, an upper control arm, and a lower control arm. Each control arm has a first end and a second end, with the first end of each control arm being pivotally connected to the frame bracket member. The suspension system also includes an axle connecting member connectable to an axle, with the second end of each control arm being pivotally connected to the axle connecting member. A compression coil spring having a first end connected to the lower control arm and a second end connected to the upper control arm serves as a lift mechanism for lifting and lowering the axle connected to the axle connecting member. The compression coil spring may encircle at least a portion of and be substantially coaxial with the lower control arm.

Abstract: A vehicle and a suspension system, for stabilizing vehicle disposition by lowering the center of gravity, and improving stability control performance are provided. The vehicle includes a body, at least one arm, a bottom unit, which may be a wheel, coupled to one end of an arm of the at least one arm, and a suspension system having a spring disposed to generate a counter moment in a direction that offsets an impact moment applied to the arm that is subjected to an impact.

Abstract: The subject matter of the present invention relates generally to a vehicle that has axles with tires mounted thereon with at least one axle that is a lift axle, and more specifically, to a method that optimizes the effective tire rolling resistance by adjusting the load on the tires, resulting in an improvement in the fuel economy of the vehicle. According to one embodiment, the method takes into consideration the rolling resistance characteristics of the tires placed onto the axles of the vehicle and provides an algorithm for optimizing their rolling resistance by raising or lowering the lift axle.

Abstract: A vehicle (3) comprising at least two axles (6, 7, 8) fitted with at least two tires the axis of rotation of which are always mutually parallel from one axle to another. Each axle (6, 7, 8) bears at least 10% of the load of the vehicle and at least two axles (6, 7, 8) bear different loads during running. Also disclosed is a method for distributing the load between said at least two axles.

Abstract: A seated vehicle comprises a frame, one or more first wheels at a first position relative to the frame, one or more second wheels at a second position relative to the frame, and a wheel-positioning system. The wheel-positioning system includes one or more arms pivotally coupled to the frame, and an adjustment mechanism operatively coupled to a first position of the one or more arms. The one or more first wheels are operatively coupled to a second position of the one or more arms. The adjustment mechanism moves the one or more arms between a first position and a second position so that the one or more first wheels are in a first position relative to the one or more second wheels when the one or more arms are in the first position and are in a second position relative to the one or more second wheels when the one or more arms are in the second position.

Abstract: An axle-lifting device for lifting an axle of a vehicle. The axle-lifting device includes a function mechanism for generating a force component in an axle-lifting direction. The function mechanism is configured to generate a first force component for providing a first functionality and a second force component for lifting the axle in the axle-lifting direction.

Abstract: A seated vehicle comprises a frame, one or more first wheels at a first position relative to the frame, one or more second wheels at a second position relative to the frame, and a wheel-positioning system. The wheel-positioning system includes one or more arms pivotally coupled to the frame, and an adjustment mechanism operatively coupled to a first position of the one or more arms. The one or more first wheels are operatively coupled to a second position of the one or more arms. The adjustment mechanism moves the one or more arms between a first position and a second position so that the one or more first wheels are in a first position relative to the one or more second wheels when the one or more arms are in the first position and are in a second position relative to the one or more second wheels when the one or more arms are in the second position.

Abstract: The stair-climbing apparatus has a series of articulating wheel sets extending below the platform. All of the wheel sets are vertically adjustable to negotiate stairways and similar changes of elevation. The lead wheel set is fixed longitudinally relative to the platform, while following wheel sets are longitudinally adjustable to adjust for the pitch or slope of different stairways. The apparatus uses sensors (e.g., mechanical, infrared, ultrasonic, etc.) to detect the presence of the stair risers and their height, control of the assembly being accomplished by a control circuit on board the machine. The wheel sets are raised and lowered independently of one another by pantograph mechanisms extending between the platform and the wheel sets. The horizontally adjustable wheel sets are positioned by a longitudinally disposed rack on the platform.

Abstract: A drive unit for a carrier that includes a chassis with a drive wheel that is pivotable with an air spring in and out of contact with a surface over which the carrier is propelled. The air spring is in a pneumatic system including an air compressor which is connected to a processor in an electrical system. The compressor is programmed to provide a fair safe mode for the drive wheel, a runtime control for the air compressor and a battery voltage sensing circuit to shut down the electrical system during periods of inactivity.

Abstract: A vehicle having a multiple of level compensation systems is disclosed. The vehicle comprising a chassis having a left frame, a right frame and a base plate, a first level compensation system comprising a pivot joint for pivotably connecting the left and right frames to the base plate around a common rotational axis. A first axial distance from a left rotation axis of a left wheel pair to the rotational axis is different from at least one second axial distance from a right rotation axis of a right wheel pair to the rotational axis, such that the left and right wheel pair have at least one off-set to each other. Moreover a method for traversing stairs with such vehicle is disclosed.

Abstract: A transport means (1) comprising: —at least two wheels (2), —a chassis (3) with a longitudinal axis, which is substantially parallel to a direction of travel of the transport means (1), and —at least one suspension system (4) operationally positioned between the chassis (3) and the wheels (2), wherein each wheel (2) has a wheel rotation axis (5), which is substantially horizontal, wherein the suspension system (4) includes a connection means (22) that interact releasably with a connection means (23) on the chassis (3), and wherein the suspension system (4) has a first orientation, wherein the suspension system (4) has at least one other orientation which is rotated in relation to the first orientation about a suspension rotation axis (6), which is substantially horizontal and perpendicular to the longitudinal axis of the chassis (3).

Abstract: A lift axle suspension system is provided with a frame bracket member connectable to a vehicle frame, an upper control arm, and a lower control arm. Each control arm has a first end and a second end, with the first end of each control arm being pivotally connected to the frame bracket member. The suspension system also includes an axle connecting member connectable to an axle, with the second end of each control arm being pivotally connected to the axle connecting member. A compression coil spring having a first end connected to the lower control arm and a second end connected to the upper control arm serves as a lift mechanism for lifting and lowering the axle connected to the axle connecting member. The compression coil spring may encircle at least a portion of and be substantially coaxial with the lower control arm.

Abstract: The stair-climbing apparatus has a series of articulating wheel sets extending below the platform. All of the wheel sets are vertically adjustable to negotiate stairways and similar changes of elevation. The lead wheel set is fixed longitudinally relative to the platform, while following wheel sets are longitudinally adjustable to adjust for the pitch or slope of different stairways. The apparatus uses sensors (e.g., mechanical, infrared, ultrasonic, etc.) to detect the presence of the stair risers and their height, control of the assembly being accomplished by a control circuit on board the machine. The wheel sets are raised and lowered independently of one another by pantograph mechanisms extending between the platform and the wheel sets. The horizontally adjustable wheel sets are positioned by a longitudinally disposed rack on the platform.

Abstract: The stair-climbing apparatus has a series of articulating wheel sets extending below the platform. All of the wheel sets are vertically adjustable to negotiate stairways and similar changes of elevation. The lead wheel set is fixed longitudinally relative to the platform, while following wheel sets are longitudinally adjustable to adjust for the pitch or slope of different stairways. The apparatus uses sensors (e.g., mechanical, infrared, ultrasonic, etc.) to detect the presence of the stair risers and their height, control of the assembly being accomplished by a control circuit on board the machine. The wheel sets are raised and lowered independently of one another by pantograph mechanisms extending between the platform and the wheel sets. The horizontally adjustable wheel sets are positioned by a longitudinally disposed rack on the platform.

Abstract: A seated vehicle comprises a frame, one or more first wheels at a first position relative to the frame, one or more second wheels at a second position relative to the frame, and a wheel-positioning system. The wheel-positioning system includes one or more arms pivotally coupled to the frame, and an adjustment mechanism operatively coupled to a first position of the one or more arms. The one or more first wheels are operatively coupled to a second position of the one or more arms. The adjustment mechanism moves the one or more arms between a first position and a second position so that the one or more first wheels are in a first position relative to the one or more second wheels when the one or more arms are in the first position and are in a second position relative to the one or more second wheels when the one or more arms are in the second position.

Abstract: A suspension system is disclosed that suspends a trailing axle with steerable wheels from the body of a motor vehicle with a carriage and a pair of actuators. The axle is directly suspended from the carriage and the actuators operate to establish the carriage and thereby the axle in a stowed condition on the vehicle body and in an active condition where the axle trails the vehicle at a substantial distance and is forced by the actuators to help support the vehicle.

Abstract: A suspension system is disclosed that suspends a trailing axle with steerable wheels from the tailgate of a motor vehicle with the use of a carriage, a pair of actuators and gas springs. The carriage is pivotally connected to the tailgate, the axle is directly suspended from the carriage and the actuators are pivotally connected to the carriage and tailgate and adapted to establish the carriage and thereby the axle in a stowed condition on the tailgate and in an active condition where the axle trails the vehicle at a substantial distance and the actuators are connected to the tailgate so as to contribute in an enhanced manner to the roll stability of the vehicle.

Abstract: An auxiliary axle suspension system for a motor vehicle is disclosed wherein a pair of hydraulically operated actuators position and force the auxiliary axle to help support the vehicle. And gas springs are provided that allow the actuators to extend and retract over a wide range of hydraulic operating pressure and thereby allow the auxiliary axle to adjust to a wide range of road grade differences between the auxiliary axle wheels and the wheels of the axles that normally support the vehicle without incurring significant gas and hydraulic pressure fluctuation and while isolating shock forces on the auxiliary axle wheels from the vehicle.

Abstract: The stair-climbing apparatus has a series of articulating wheel sets extending below the platform. All of the wheel sets are vertically adjustable to negotiate stairways and similar changes of elevation. The lead wheel set is fixed longitudinally relative to the platform, while following wheel sets are longitudinally adjustable to adjust for the pitch or slope of different stairways. The apparatus uses sensors (e.g., mechanical, infrared, ultrasonic, etc.) to detect the presence of the stair risers and their height, control of the assembly being accomplished by a control circuit on board the machine. The wheel sets are raised and lowered independently of one another by pantograph mechanisms extending between the platform and the wheel sets. The horizontally adjustable wheel sets are positioned by a longitudinally disposed rack on the platform.

Abstract: A wheelchair includes a frame, a chair, a pair of drive wheels, a pair of rear wheels, and a pair of front wheels. Each front wheel is part of a front arm assembly that is rigidly coupled to a drive via a mounting plate. The mounting plate is connected to the wheelchair frame by a pivot. The drives are transversely mounted. The batteries are disposed rearward of the drives. The wheelchair seat can be moved forward to provide access to the batteries without fully removing the wheelchair from the frame.

Abstract: A vehicle (10) comprising a vehicle body, a suspension system coupled to the vehicle body, and a plurality of wheels (16) coupled to the suspension system comprising at least one pair of wheels, each wheel of the at least one pair of wheels being located on opposite sides of the vehicle. The suspension system comprises a changeable wheel track width for the at least one pair of wheels and the wheel track width is changeable between a narrow wheel track width setting (12) and a wide wheel track width setting (14) by pivoting a suspension link (18) about a vertical axis.

Abstract: A wheelchair includes a frame, a chair, a pair of drive wheels, a pair of rear wheels, and a pair of front wheels. Each front wheel is part of a front arm assembly that is rigidly coupled to a drive via a mounting plate. The mounting plate is connected to the wheelchair frame by a pivot. The drives are transversely mounted. The batteries are disposed rearward of the drives. The wheelchair seat can be moved forward to provide access to the batteries without fully removing the wheelchair from the frame.

Abstract: A wheel set structure of an electric wheelchair is disclosed to include a wheelchair frame, which defines a first steering direction and a second steering direction reversed to the first steering direction, at least one swinging mechanism pivotally mounted on the wheelchair frame each having a swinging member and a wheel holder, at least one transmission wheel assembly connected to the swinging member each having a motor and a driving wheel coupled to and rotatable by the motor, and at least one first wheel assembly mounted on the wheel holder each pivotally holding a wheel. When the at least one swinging member is biased relative to the at least one wheelchair frame, the at least one first wheel assembly is biased with the at least one swinging member so that the elevation of the wheel of each first wheel assembly and the elevation of the driving wheel of each transmission wheel assembly are relatively changed at a constant ratio.

Abstract: The present invention provides a tag axle attachment for an off-road agricultural vehicle. The tag axle attachment allows agricultural vehicles to meet roadway weight restrictions imposed by the federal and state governments while also allowing the vehicle to perform optimally in the field. The tag axle is assembled such that it can be hydraulically lowered into a deployed position when the agricultural vehicle is on the roadway and hydraulically raised into a stowed position when the agricultural vehicle is in the field. The tag axle assembly is mounted to the chassis rails of an agricultural vehicle and positioned to fit between the chassis rails when stowed and minimizes the load per axle of the vehicle when deployed.

Abstract: The present invention is a drop-down extra axle and wheel set for a utility truck. The extra axle and wheels are pivotally connected to an extra frame set that overlies and/or extends along the original frame for the truck, from the back end of the truck frame to near its midpoint just behind the cab of the truck. The extra frame set is a generally horizontal, rectangular piece that lays over the top of, and/or extends along, from the back end of to just behind the cab of, the original truck frame. The extra frame set has a trailing, extra, axle support assembly near its back end. The extra axle support assembly depends down from the extra frame, and supports an extra axle and wheel set at its bottom. A set of pivoting connecting rods extend forwardly from the bottom of the extra axle support assembly to pivot brackets which also depend down from the extra frame several feet forward of the extra axle support assembly.

Abstract: A payload-carrying motor vehicle comprises a steer axle, at least one drive axle and a tag axle. All of the axles have wheels with tires and air brakes and a tag axle suspension system is adapted to suspend the tag axle in an active condition wherein the tag axle is pivotal about a first axis parallel to the other axles and also about a second axis located equidistant from the tag axle wheels and laying in a plane at right angles to the first axis and wherein the tag axle is forced to urge the tag axle tires against a road surface to aid in supporting the vehicle. An air brake system is adapted to operate the air brakes of all the wheels and a tag axle operating system is adapted to establish the tag axle in the active condition while enabling operation of the air brakes of the tag axle wheels and to disable operation of the air brakes of the tag axle wheels when the tag axle pivots about the second axis and reaches a predetermined tilt angle in maintaining contact of the tag axle tires with a road surface.

Abstract: A payload-carrying motor vehicle comprises a frame, a steer axle, tandem drive axles, at least one pusher axle located between the steer axle and drive axles, and a tag axle. A steer axle suspension system suspends the steer axle from the frame, a drive axle suspension system suspends the drive axles from the frame, a pusher axle suspension system including gas springs suspends the pusher axle from the frame, and a tag axle suspension system including a primary tag axle suspension and a secondary tag axle suspension suspends the tag axle from the frame behind the drive axles. The primary tag axle suspension suspends the tag axle for pivotal movement about an axis parallel to the other axles and includes actuators incorporating a gas spring forcing the tag axle tires against a road surface to aid in supporting the frame.

Abstract: A wheelchair includes a frame, a chair, a pair of drive wheels, a pair of rear wheels, and a pair of front wheels. Each front wheel is part of a front arm assembly that is rigidly coupled to a drive via a mounting plate. The mounting plate is connected to the wheelchair frame by a pivot. The drives are transversely mounted. The batteries are disposed rearward of the drives. The wheelchair seat can be moved forward to provide access to the batteries without fully removing the wheelchair from the frame.