Abstract: An agricultural mower system includes: a towing vehicle including an engine and a tongue coupler and defining a towing centerline; a mower including a frame carrying cutters and pivotably coupled to a tongue that is pivotably coupled to the tongue coupler, the frame defining a mower centerline that is offset from the towing centerline, the tongue defining a towing angle with respect to the towing centerline and a mower angle with respect to the mower centerline; a mower angle actuator coupled to the tongue and the frame; and a controller configured to: determine the towing angle has changed by a change amount relative to a defined towing angle; determine a turn compensation amount for the mower angle as a function of the change amount and a constant; and output a compensation signal to cause the mower angle actuator to adjust the mower angle by the determined turn compensation amount.

Abstract: A vehicle parameter estimation module is configured to generate a first estimate of a vehicle parameter based on operating conditions of a vehicle measured or estimated at a first time. The vehicle parameter includes at least one of a tire cornering stiffness of the vehicle and an understeer coefficient of the vehicle. The vehicle parameter estimation module is also configured to determine an error value based on the first estimate of the vehicle parameter and values of the vehicle operating conditions measured or estimated at a second time that is later than the first time. The vehicle parameter estimation module is further configured to generate a second estimate of the vehicle parameter based on the first estimate of the vehicle parameter and the error value. A vehicle actuator control module is configured to control an actuator of the vehicle based on the second estimate of the vehicle parameter.

Abstract: The vehicle system can include: a set of vehicle couplings (e.g., a tractor interface, a trailer interface, etc.); a chassis, a battery pack, an electric powertrain, a sensor suite, and a controller. The modular vehicle system can optionally include landing gear, a suspension, and any other suitable set of components. The vehicle system functions to structurally support and/or tow a trailer—such as a Class 8 semi-trailer—and/or to augment/supplement a tractor propulsive capability (e.g., via a diesel/combustion engine) with a supplementary electric drive axle(s).

Abstract: The technology relates to fine maneuver control of large autonomous vehicles that employ multiple sets of independently actuated wheels. The control is able to optimize the turning radius, effectively negotiate curves, turns, and clear static objects of varying heights. Each wheel or wheel set is configured to adjust individually via control of an on-board computer system. Received sensor data and a physical model of the vehicle can be used for route planning and selecting maneuver operations in accordance with the additional degrees of freedom provided by the independently actuated wheels. This can include making turns, moving into or out of parking spaces, driving along narrow or congested roads, construction zones, loading docks, etc. A given maneuver may include maintaining a minimum threshold distance from a neighboring vehicle or other object.

Abstract: A system and/or a method for integrated auto-steering apparatus, auto-braking apparatus and auto-acceleration apparatus to facilitate actuating brake and turning steering wheel without a driver. The technology may be made as a part of Drive-By-Wire system to make the system retrofit using a spur gear train connected through a motor to make steering automatic, and using an electric actuator to make braking automatic, and integrating all the apparatus though a programmable logic controller to achieve navigation of autonomous vehicle. The complete system design fits at the steering column and the brake pedal to imitate exact behavior of human with sensor feedback system.

Abstract: The present disclosure provides a rear wheel steering (RWS) control method and system for a cargo trailer. The RWS control method may include determining a driving mode of a vehicle connected to the cargo trailer, executing an RWS control logic of the cargo trailer based on the driving mode and an input signal from the vehicle corresponding to the driving mode, and performing RWS control for the cargo trailer based on the RWS control logic.

Abstract: The present disclosure relates to a steering system for an agricultural machine. The steering system includes a first and second wheel assembly. Each wheel assembly includes an axle assembly including an axle, wheels rotatably connected to the axle, and a double-action hydraulic cylinder. In some embodiments, the double-action hydraulic cylinder is configured to pivot the wheels in either direction to indicate a direction of turn. In some embodiments, the double-action hydraulic cylinder of the first wheel assembly is hydraulically linked in its operation to an operation of the double-action hydraulic cylinder of the second wheel assembly.

Abstract: Disclosed is a trailer including a bed portion. The bed portion includes a deck, a front extension, and a rear extension. The deck has a first end and a second end. The front extension is slideably engaged with the first end of the deck, and the rear extension is slideably engaged with the second end of the deck. The trailer is a “double stretch” trailer that is extendable from both ends of the deck. A towing system including a cab and the trailer is also disclosed.

Abstract: An agricultural hitch with a system for management and guidance of maneuvers and a method employed by the hitch is provided. The hitch includes a tractor, an agricultural machine hitched by an articulated linkage, and a system for management and guidance of maneuvers, provided with a computing and control unit. The computing and control unit or of the hitched agricultural machine constitutes the master unit of the system for management and guidance of maneuvers, and is adapted to compute a set path for a maneuver to come, by employing an algorithm for prediction of paths and an algorithm for optimization of path settings, and to automatically execute the maneuver or of assisting in semiautomatic execution of the maneuver by steering the tractor and by recording, during maneuvering, the differences between the predefined set path and the real or currently estimated path.

Abstract: The present invention relates to a transport device for a milling unit of a road milling machine, the milling unit comprising a milling drum box and a milling drum. Essential elements of the transport device include a support frame, a rotating device and a transport vehicle connector. The present invention further relates to a transport vehicle with a carrier vehicle and a transport device, as well as a method.

Abstract: A hitch assist system and method are provided herein. An imager is configured to capture one or more images containing a trailer having a hitch coupler. A touchscreen display is configured to show a view of the trailer and register one or more touch events thereon for specifying a location of the hitch coupler. A controller is configured to generate an icon at the specified location of the hitch coupler.

Abstract: The disclosure relates to a steering system useful for providing stable control during rear axle steering of harvesters, such as self-propelled windrowers. The steering system utilizes a single steering cylinder and retracted caster cylinders to regulate rotation of the casters during rear axle road operation mode. The steering system locks the steering cylinder and uses the caster cylinders for damping during in-field operation mode.

Abstract: A control system for a steering a work machine is disclosed. The control system may include a steering input device configured to steer a lead machine module and an articulation module disposed between the lead machine module and a trailing machine module. The control system may further include a first articulation cylinder and a second articulation cylinder configured to actuate between a first and second cylinder first position and a first and second cylinder second position. Furthermore, an electronic controller in communication with the first and second articulation cylinders and programmed to transmit a control signal such that the first actuation cylinder actuates between the first actuation cylinder first position and the first actuation cylinder second position and the second actuation cylinder actuates between the second actuation cylinder first position and the second actuation cylinder second position.

Abstract: The present invention relates to a vehicle control system (1) for controlling a vehicle (3) to facilitate reversing a trailer (5) coupled to the vehicle (3). The vehicle control system includes a processor (33) configured to receive a target trailer destination (DTAR). The current position of the trailer (5) is determined by the processor (33). A target route (R) is then modelled to guide the trailer (5) from its current position to the target trailer destination (DTAR). The processor (33) is configured to output a vehicle control signal to control the vehicle (3) to guide the trailer (5) along the target route (R). The invention also relates to a method of controlling a vehicle (3) to facilitate reversing a trailer (5).

Abstract: A trailer backup assist system for a vehicle reversing a trailer is provided herein. The system includes a brake system and a steering system of the vehicle. A controller is configured to output a brake torque request to the brake system and a steering command to the steering system, wherein the brake torque request and the steering command are each based at least in part on a trailer mass.

Abstract: A system for determining a hitch angle between a vehicle and a trailer is provided herein. An imaging device is configured to capture images of the trailer. A controller is configured to process image data to determine an optical flow. The controller distinguishes between optical flow vectors of pixels associated with the trailer and an operating environment. The controller calculates an average angular velocity for the pixels associated with the trailer and determines the hitch angle based on the average angular velocity.

Abstract: The present invention is a guidance computing system used by the driver of a vehicle towing a trailer while backing-up that rapidly calculates and predicts the direction in which the tow vehicle and trailer will become generally in-line for a given position of the steering wheel, thereby enabling the use of slower, lower cost microcomputers. This is accomplished by using a predetermined table, based on a baseline trailer of known length, having a measure of turning as one of its axes; such an axis is necessary to facilitate ratiometric scaling to convert table values to correspond to any length trailer. In a specially equipped vehicle incorporating servomechanisms to enable the vehicle to steer itself, the driver indicates the direction desired for the trailer to travel. The present invention also predicts left and right path limits for controlling the direction of the trailer when maneuvering complex paths.

Abstract: A trailer backup assist system for vehicles utilizes surface slope data to provide an alert to an operator if a problematic operating condition is present and/or imminent while the vehicle is backing up with a trailer attached thereto. The trailer backup assist system may also be configured to utilize surface slope data to control steering, braking, or other vehicle operating parameter while the vehicle is backing up with a trailer attached thereto. The trailer backup assist system may also be configured to generate a warning and/or control the vehicle if a jackknife condition is imminent. The surface slope data may be obtained utilizing sensors on the vehicle, or the surface slope data may be obtained utilizing a database that includes topographical data.

Abstract: A system for detecting a hitch angle between a vehicle and a trailer is provided herein. An imaging device is configured to capture images of the trailer and a controller is configured to process images captured by the imaging device. The controller derives a template image having a trailer contour and matches the template image to a search image. The hitch angle is determined based on a positional relationship between the template image and the search image.

Abstract: A trailer backup assist system includes a sensor that measures a hitch angle between a vehicle and a trailer. A steering system controls a steering angle of the vehicle between physical angle limits. A controller of the trailer backup assist system generates adaptive angle limits based on a maximum hitch angle rate and generates a steering command within the physical and adaptive angle limits for the vehicle to guide the trailer on a desired curvature.

Abstract: A traction control assembly for connection between a monorail bogie frame and a monorail car. The traction control assembly comprising a first traction link pivotally connected to a first bell crank mechanism and a second traction link pivotally connected to a second bell crank mechanism. The first traction link and the second traction link are capable of absorbing traction forces applied to the monorail bogie. The traction control assembly further comprises a cross link interconnecting the first bell crank mechanism and the second bell crank mechanism and a passive steering assist device interconnecting the first bell crank mechanism and the second bell crank mechanism. The steering assist device causes the traction control assembly to insert shear forces on the monorail bogie during travel of the monorail bogie over a curved section of monorail track for facilitating rotational motion between the monorail bogie and the monorail car.

Abstract: A vehicle system for estimating a trailer length is disclosed. The system incorporates at least one sensor configured to measure a wheel steer angle and a trailer angle in communication with a processor. The processor is operable to determine a first length by a first computation method and determine a second length by a second computation method. The processor is further operable to validate an estimated trailer length based on the first length and the second length and perform a back-up function for the trailer based on the estimated trailer length.

Abstract: Saddle type self-steer axle systems equipped wagons may include two or more axles and may be backed up due to reversing caster. Such systems may provide increased stability by providing four points of contact. Further, such systems may provide improved weight distribution in that weight may be distributed over four points as opposed to three points. In addition, such systems may provide increased safety by raising the rollover threshold to that of the tow vehicle. Such systems may allow a tow vehicle to carry its full allowable gross weight while towing its full allowable tow weight. In addition, a centrally pivoting saddle style hinge system may reduce the actuator force that may be needed to change the caster from forward to reverse and vice versa.

Abstract: A system and a method are provided for calibrating a backup assist system for a trailer attached to a vehicle. The method includes driving the vehicle forward substantially straight above a threshold speed, sensing a yaw rate of the vehicle, and sensing a measured hitch angle of the trailer. A yaw sensor continuously senses the yaw rate of the vehicle and a hitch sensor continuously measures the hitch angle for determining an angle rate based on the measured hitch angle. Further, a controller determines an offset between the measured hitch angle and an actual hitch angle when the yaw rate and angle rate are substantially zero or otherwise the same.

Abstract: Methods and apparatus for automatically adjusting the angle of a rotatable side view mirror of an articulated tractor and trailer includes transducers attached to the tractor for transmitting signals toward the trailer and for receiving signals reflected by the trailer. The transducers have a substantially symmetrical arrangement about a centerline of a linear transducer bar attached to the tractor and each has an angular orientation substantially dissimilar to adjacent transducers on a same side of the centerline. A control circuit sequentially activates ones of the transducers such that only a single transducer transmits signals at any given time. Thereafter, the control circuit only processes reflected signals received by the emitting transducer. The control circuit calculates an angle between the tractor and trailer and causes the mirrors to rotate. Transducer calibration and mirror adjustment relative to a zero position set by a driver are also contemplated.

Abstract: Apparatus for measuring the articulation angle between a tractor and trailer connected by a kingpin and fifth wheel include a transfer assembly associated with the kingpin and interacting with the fifth wheel such that the transfer assembly is rotationally moved relative to the kingpin by relative rotational movement between the kingpin and the fifth wheel. This rotational movement is read by an articulation sensing mechanism having one of a reader element and output element mounted to the transfer assembly and the other of the reader element and the output element operatively mounted to the trailer such that the reader element and the output element interact to provide a signal corresponding to the articulation angle between the tractor and trailer. This signal can be analyzed by a processor for any beneficial use, for example, outputting to a counter steering mechanism.

Abstract: A vehicle has a trailer backup steering input apparatus, a trailer backup assist control module coupled to the a trailer backup steering input apparatus, and an electric power assist steering system coupled to the trailer backup assist control module and. The trailer backup steering input apparatus is configured for outputting a trailer path curvature signal approximating a desired curvature for a path of travel of a trailer towably coupled to the vehicle. The trailer backup assist control module is configured for determining vehicle steering information as a function of the trailer path curvature signa. The electric power assist steering system is configured for controlling steering of steered wheels of the vehicle as a function of the vehicle steering information.

Abstract: A steering system for a towed farm implement or wagon, such as a header transport, is provided that allows the tongue of the header transport to pivot approximately 90 degrees to the right or the left (i.e., 180 degrees in total) and translates the movement of the tongue to all of the wheels of the header transport. Front steering linkages are coupled to the tongue, and are configured to oscillate front wheels in response to rotation of the tongue. Rear steering linkages are coupled to the front steering linkages by front-to-rear linkages, and the rear steering linkages are configured to oscillate rear wheels in response to rotation of the tongue.

Abstract: A method of controlling a combination vehicle for road transport of heavy goods, said vehicle comprising a motor vehicle at the front and a trailer attached so as to be towed behind the motor vehicle, said trailer comprising: (a) a semi-trailer body adapted to carry goods, (b) a dolly mounted beneath the front of the semi-trailer body and connected to the semi-trailer body by a pivoting connection, said dolly comprising road wheels attached in one or more axle sets to a dolly frame, each axle set extending across the dolly frame, and (c) a drawbar assembly connecting the dolly frame to a preceding vehicle unit by means of a trailer coupling assembly, wherein: (i) the drawbar assembly defines an instant centre of rotation for the dolly which is located forwards of said trailer coupling assembly while the vehicle is moving forwards at high road speeds, and (ii) the drawbar assembly defines an instant centre of rotation for the dolly which is located at least substantially at the trailer coupling assembly while

Abstract: A steerable trailer provides the ability to offset the center line of the trailer to the tow vehicle with a swivel tung and pivoting axels. The steerable trailer can alter the turning radius of the trailer and improve the turning and backing of the trailer. Typically, a trailer moves relative to the tow vehicle. The steerable trailer allows a user to control the trailer steering independently from the tow vehicle and adds up to two more points to steer more accurately and safely in close areas, for example. The swiveling tung and pivoting axels can be used independently or together to position the trailer safely in different radii.

Abstract: The present invention relates to removal of excavated rock material in mine and underground as well as surface excavation, and particularly to transport equipment suitable for transporting excavated rock material. The transport equipment suitable for transporting excavated rock material according to the invention comprises a trailer connectable to a body of the transport equipment by a fastening articulation, the trailer comprising a body of the trailer, a transport box of the trailer, and a plurality of wheels of which at least two are arranged to be steerable wheels.

Abstract: A driving support device for a first trailer coupling vehicle including a first trailer and a first towing vehicle includes: a leading vehicle driving status obtaining device for obtaining a driving status of a second trailer coupling vehicle; a first towing vehicle driving status obtaining device for successively obtaining a driving status of the first towing vehicle; a first trailer driving status obtaining device for successively obtaining a driving status of the first trailer; and a support device for supporting a driver of the first trailer coupling vehicle so as to bring the driving status of the first towing vehicle and the driving status of the first trailer closer to the driving status of a second towing vehicle and the driving status of a second trailer, respectively, when the first trailer coupling vehicle changes in direction.

Abstract: A steerable agricultural implement configured to be coupled to a tractor by a multi-point hitch system that restrains side-to-side articulation between the tractor and the implement. The agricultural implement includes a steering controller that receives a positional attribute from a steering system of the tractor and controls a degree of pivot of a wheel assembly of the agricultural implement based on the positional attribute of the tractor steering system. The wheel assembly is configured with a steering actuator that is operable to pivot a portion of the wheel assembly without transmitting force beyond the wheel assembly, abutment stops to define maximum degrees of pivot of the portion of the wheel assembly and relieve the steering actuator without transmitting force beyond the wheel assembly, and a quick release free-wheel mechanism to enable a disconnected or “free wheel” operation of the wheel assembly independent of the steering actuator.

Abstract: A steerable rear assembly is disclosed for a lowboy trailer. The assembly includes a lowboy trailer deck and a neck extending partially upwardly rearward and partially horizontally rearward from the deck. A front bogey is positioned beneath the horizontally extending portion of the neck, and the front bogey is connected to the neck by a horizontal pivot between the neck and the front bogey and by a turntable between the neck and the front bogey. A rear bogey is positioned behind the front bogey and is connected to the front bogey by a vertical pivot between the front and rear bogeys.

Abstract: An articulated machine and method of operation, the articulated machine having a first frame with a first traction device and a steering apparatus that controls a steering angle thereof, the first frame pivotally coupled to a second frame at an articulation joint, the second frame having a second traction device, a steering sensor configured to provide a steering signal indicative of the steering angle, and an electronic controller configured to automatically control an articulation angle based on the steering signal.

Abstract: The present invention features an automobile hauling system for improved maneuverability and hauling capacity for a tractor and trailer combination used to transport automobiles. The system features a cab-over automobile hauling tractor having an extended wheelbase frame with first and second side notches. The tractor features a first steering axle assembly, a second steering axle assembly, and an h-link. A pitman arm first end is located on a steering box and a pitman arm second end is pivotally located on a first drag link. The tractor features a supplemental axle assembly and a drive axle assembly located on the frame bottom. The system features an automobile hauling trailer pivotally located on the frame top side.

Abstract: A steering mechanism for a drawn vehicle to steer one or more turnable steered axles that at least has a slewing bearing, a rocker that is fitted around a vertical shaft and is turnable, a cable whose ends are connected to the rocker on either side of the vertical shaft and which is fitted around the slewing bearing to transmit a turn of the slewing bearing to the rocker and a tackle at each end of the cable with a fixed pulley that can be coupled to the drawn vehicle, and a movable pulley on the rocker.

Abstract: A suspension system for a steerable trailer includes a strut which is mounted to the frame of the trailer, an axle which is connected to the strut, and far and near suspension cylinders which connect the axle to the frame. The far and near suspension cylinders connect to opposite side of the axle. Steering rods connect adjacent axles together, the steering rod connection alternating between the left and right side of the frame.

Abstract: Saddle type self-steer axle systems equipped wagons may include two or more axles and may be backed up due to reversing caster. Such systems may provide increased stability by providing four points of contact. Further, such systems may provide improved weight distribution in that weight may be distributed over four points as opposed to three points. In addition, such systems may provide increased safety by raising the rollover threshold to that of the tow vehicle. Such systems may allow a tow vehicle to carry its full allowable gross weight while towing its full allowable tow weight. In addition, a centrally pivoting saddle style hinge system may reduce the actuator force that may be needed to change the caster from forward to reverse and vice versa.

Abstract: A steering angle warning system comprising a rotation-measuring unit located on an aircraft, and an alarm unit. The rotation-measuring unit is arranged to output a first signal dependent on the steering angle between a nose landing gear of the aircraft and the longitudinal axis of the aircraft fuselage. The alarm unit is arranged to generate an alarm, in dependence on the first signal, when the steering angle is greater than a predetermined value, for example, 60 degrees. The rotation-measuring unit may also be arranged to perform a function in relation to an aircraft steering system, for example to indicate the steering angle to the pilot during ground manoeuvres.

Abstract: The invention relates to a method for determining a set steering angle ?o of steered wheels of a vehicle comprising a tractor and a trailer that is articulated with regard to the tractor. This method makes it possible to produce a set value that can be used for various purposes. This set value can thus be used for controlling an actuator acting upon the steering angle or for being communicated in order to inform the driver. According to the invention, during reversing maneuvers: based on a target point C via which the driver would like the path of the vehicle to pass, an angle set value ?c between the axes of the trailer and of the tractor is determined according to said target point C and to the dimensions of the vehicle, and; the set steering angle ? of the steered wheels is determined according to a servo-system causing the measured angle ? between the axis of the trailer and the tractor to tend toward said angle set value ?c.

Abstract: An amputee mobility device includes a wheeled frame, and seat with webbed pocket for receiving an amputated leg. The seat is adjustable height adjustable, as is the pocket for customizing to individuals. Adjustable handles allow amputees to move themselves, or allow a helper to push like a wheelchair. In one form, the frame includes front and rear articulated subframes. In another form, the wheeled frame forms an elongated rigid frame, with two fixed-axle wheels and two rear-located steerable wheels and one front-located steerable wheel. In another form, the frame includes two fixed-axle wheels and two steerable wheels arranged to function somewhat like a wheeled walking cane. Optional features include outriggers for leg protection, a foldable frame for compact storage and shipment, bicycle-like lockable hand brakes, a seat without aperture for supporting a lower leg extending horizontally, storage shelves, and cup holders.

Abstract: A steering system and method are capable of steering a plurality of vehicles arranged in a train with adjacent vehicles pivotally connected to each other for movement about a vertical axis. Each vehicle has a pair of steerable wheels with one pair at one end of the train being a selected leading pair having its steering angle determined by an operator. An electrical control system automatically steers all of the wheels trailing behind the leading pair. Vehicle angle sensors measure intercar angles between adjacent vehicles and provide this information to the control system. An indicator provides the controller with the current distance traveled by the train. Wheel angle sensors provide signals indicative of the current steering angle for each wheel pair. The controller adjusts the actual steering angle for each trailing pair to a desired angle by calculating adjustments based on the measurement inputs.

Abstract: An oscillating in-line steering system for a pulled agricultural implement includes first and second in-line axles pivotably coupled with a frame. The system also includes at least first and second in-line wheel arrangements pivotably coupled with the first and second axles respectively. Each wheel arrangement has a plurality of pivotable wheel assemblies arranged in-line and wheel linkages coupling the in-line wheel assemblies such that in-line wheel assemblies oscillate together. A right-to-left linkage couples the wheel linkage of the first in-line wheel arrangement to the wheel linkage of the second in-line wheel arrangement so that the first in-line wheel arrangement oscillates at a steering angle proportional to that of the second in-line wheel arrangement.

Abstract: A tractor/trailer combination wherein a trailer is connected to a tractor through the connection of a kingpin with a fifth wheel is provided with a trailer steering system. Using given dimensions of the tractor/trailer combination and a measured articulation angle between the tractor and trailer during a turn, the wheels of the rear axles of the trailer are turned so that they turn approximately about the instant center established for the tractor. In this way, the trailer turns around approximately the same point as does the tractor, thus significantly eliminating off tracking.

Abstract: A steering system for a tractor and trailer includes first and second sender cylinders which are turned 180° with respect to each other, and first and second receiver cylinders which are turned 180° with respect to each other. First and second front link members connect the first and second sender cylinders to a front equalizer arm, and first and second rear link members connect the first and second receiver cylinders to a rear equalizer arm. The pistons of the cylinders travel in straight paths experiencing no side loads, and each piston travels the same distance as the tractor turns with respect to the trailer.

Abstract: Exemplary apparatus and system for repositioning a semi-trailer are described. The repositoner may comprise two pivoting arms, each comprising a mechanical actuator attached to an underside area of the semi-trailer, wherein the pivoting arms are disposed substantially parallel to the underside of the semi-trailer in a first position and are configured to be pivoted away from the semi-trailer in a second position substantially perpendicular to the underside of the semi-trailer; two wheels mounted at an angle from a rear plane of the semi-trailer such that the semi-trailer moves in a circular path when the wheels turn, with each wheel operatively coupled to a motor; and a lower frame mounted to the mechanical actuators of the arms, the lower frame comprising two opposing wheel housing couple to the wheels; wherein, lowering the hydraulic jack arms can hydraulically lift the semi-trailer, and further wherein the wheels can maneuver the semi-trailer.

Abstract: A method of controlling the sideways motion of a trailer forming part of a combination vehicle, such as a road train, for road transport of heavy goods. The vehicle has a trailer including a semi-trailer body and a dolly mounted beneath the front of the semi-trailer body. The method includes steering at least some of the wheels on said axle sets relative to the dolly frame such that at high speeds, as the vehicle turns towards one side, steering the dolly wheels to induce the dolly to move towards that side and, at low speeds, as said vehicle turns towards that side, steering the dolly wheels to induce the dolly to move towards the opposite side.

Abstract: A trailer having a frame assembly with front and rear axle beams rotationally coupled to the frame assembly. At least one member interconnects the front and rear axle beams to synchronize movement of the axle beams allowing the front and rear wheels to track one another. In one embodiment a first member connects the right front axle beam with the left rear axle beam and a second member connects the left front axle beam with the right rear axle beam causing the rear axle beam to rotate in the opposite direction of the front axle beam when the front axle beam turns. The push-pull operation of the members cause the rear wheels to track the front wheels.

Abstract: A powered towing vehicle having steering wheels and a wheeled trailer is connected to the vehicle for its towing. The wheels of the trailer are connected to a source of power for generating forward and rearward movement of the trailer. These wheels also are connected to a source of power for turning such wheels in order to steer the trailer. These wheels further are connected to a sensor to sense the position of the trailer wheels as they are being steered. The steering wheels of the towing vehicle also are connected to a sensor to sense the position of the vehicle wheels as they are being steered. The trailer steering wheel sensor is displayed to an operator of the vehicle so that the vehicle operator knows the relative position of each of the steering wheels. The trailer steering power source is connected to the vehicle so that an operator of the vehicle can remotely steer the wheels of the trailer.