1457 results about "Control arm" patented technology

The invention discloses an immersive master-slave teleoperation anthropomorphic robot system with force feedback, a master end assembly comprises a seat, a master end control arm, a force feedback manipulator, a VR visual device, a data sensing glove and a master end controller, and the master end assembly is a master control end; the slave end assembly comprises a movable chassis, a movable trunk, a slave end mechanical arm, a slave end manipulator, a binocular camera and a slave end controller, and the slave end controller is in electric signal connection with the movable chassis, the movable trunk, the slave end mechanical arm, the slave end manipulator, the binocular camera, the six-dimensional torque sensor and the master end controller; the wireless controller is in electric signal connection with the master end controller and the slave end controller, the wireless controller has a slave end control mode and a force feedback teleoperation mode, and in the slave end control mode, the wireless controller controls the movable chassis to move; in the force feedback teleoperation mode, the master end control arm and the force feedback mechanical arm synchronously move with the slave end mechanical arm and the slave end mechanical arm correspondingly.

A control arm includes a first and a second arm section pivotably connected to each other. A control part is coupled to the first arm section and includes a control surface. A thrust piece is mounted on the second arm section and includes a counter control surface. At least one spring element biases the thrust piece relative to the control piece. The arm sections are pivoted relative to one another and the relative movement between the control part and the thrust piece is a rolling movement.

The invention is suitable for the technical field of automobile chassis, and provides an angle module system and a modular extensible chassis, and the angle module system adopts an unequal-length double-wishbone suspension and has good geometric kinematics characteristics. And the offset distance of the main pin is reasonably controlled through the design of steering knuckle parts. By adopting the angle module bracket, the efficient integration of the driving unit and the frame structure is realized, the number of connecting points of the angle module system and the chassis is reduced, and the serialization, integration and modularization of the chassis system are facilitated. A distributed main pin steering gear is adopted, and the geometrical shape design of upper and lower control arms of the suspension is matched, so that wheels have a larger turning angle range, and the maneuverability is improved. In addition, the modular extensible chassis adopts modular design, and the number of shafts can be flexibly configured according to carrying requirements.

The invention relates to the technical field of hardness detection, in particular to an automatic hardness detection device for automobile control arm production, which comprises a detection table, an automatic durometer is mounted on the detection table, two manipulators are fixedly mounted on the detection table on two sides of the durometer respectively, a turntable is mounted on the automatic durometer, and a polishing pad is fixedly mounted on the lower surface of the turntable. A through hole is formed in the rotary disc, a telescopic groove is formed in the rotary disc, a plunger is installed in the telescopic groove, an air outlet channel is formed in the inner wall of the telescopic groove below the plunger, a vertical groove is coaxially formed in the bottom end of the plunger, an air inlet hole communicated with the vertical groove is formed in the surface of the side, close to the motor, of the plunger, and an air guide channel is formed in the inner wall of the telescopic groove and corresponds to the air inlet hole. And the plunger is in transmission connection with a driving module. Through the arrangement of the turntable and the like, the polishing pad on the turntable can be used for automatically polishing the surface of the detection point of the control arm, and blowing can be performed after polishing is completed, so that the detection efficiency can be improved, and the detection precision can also be improved.

The invention relates to an integrated control arm assembly special for a heavy-duty vehicle. The integrated control arm assembly is composed of a control arm body (1), a self-lubricating bearing (2), a self-lubricating bush (3), a ball pin (4), a lower ball bowl (5), a screw (6), a gasket (7), a first clamp (8), a second clamp (9) and a dust cover (10). The control arm body (1) is integrally forged and formed and is a main bearing part, one side of the control arm body is connected with a vehicle body through a pin shaft, and the other side of the control arm body is connected with a steering knuckle through a ball hinge. The invention is applied to a lower cross arm of a McLewis suspension of a heavy-duty vehicle or an upper cross arm and a lower cross arm of a double-cross-arm suspension, and is suitable for effectively supporting and connecting wheels and a vehicle body when the wheeled heavy-duty vehicle passes through complex road surfaces such as desert, muddy or icy and snowy road surfaces, so that the suspension reliability of the wheeled vehicle is improved. The control arm assembly structure has the advantages of being high in bearing capacity, free of maintenance of the ball hinge, reliable in structure and convenient and fast to install.

The utility model discloses an automatic line one-die multi-piece automobile aluminum alloy control arm die forging die, which relates to the technical field of forging forming, and comprises a main body structure, the main body structure comprises a lower die ejector and an upper die, the left side and the right side of the lower die ejector are fixedly provided with four die lifting beams through bolts, and the die lifting beams are used for transferring the die. The distance between the four die lifting beams is equal to the distance between die fork arms of a die changing trolley, the lower die ejector and the upper die are connected through the upper and lower die guide columns and play a guiding role in the die heating and reinforcing process, a profiled groove is formed in the bottom of the lower die ejector, and a multi-connecting-rod ejector rod is installed in the profiled groove. The lower end of the ejector rod is connected with the ejector rod tray through a bolt, and the ejector rod can horizontally eject two products at the same time. According to the utility model, a short-process forging process combining special-shaped blank casting and die forging is met, automatic production is realized, and finally, energy conservation and environmental protection are realized.

An off-road vehicle includes a frame; front and rear wheels; a front suspension assembly; a front torsion bar assembly, a rear suspension assembly and a rear torsion bar assembly. The front suspension assembly comprises a front lower rocker arm, a front upper rocker arm, and a front wheel shaft support assembly mounted between the front lower and the front upper rocker arms. The front torsion bar assembly is located above the front upper rocker arm, and is movably connected to the front upper rocker arm. The rear suspension assembly comprises a rear lower rocker arm, a rear upper rocker arm, a control arm assembly, and a rear wheel shaft support assembly mounted between the rear lower and rear upper rocker arms. The rear torsion bar assembly is located between the rear upper and lower rocker arms, and is movably connected to the rear upper rocker arm.

A control arm assembly for a vehicle includes a control arm, a spring seat, a shock absorber mount, and a spring. The control arm has an upper surface, a lower surface, and an opening extending through the upper surface and the lower surface. The spring seat has an upper surface connected to the lower surface of the control arm. The shock absorber mount is connected to the upper surface of the spring seat. The shock absorber has a first end connected to the shock absorber mount. The spring at least partially surrounds the shock absorber and has a first end contacting the upper surface of the spring seat.

The invention relates to a subframe (14) for a motor vehicle, comprising a first attachment point (26) via which a first wheel guide (20) designed to guide a vehicle wheel (18) of the motor vehicle can be pivotally coupled to the subframe (14), and a second attachment point (28) spaced apart from the first attachment point (26), via which a second wheel guide (22) designed separately from the first wheel guide (20) and designed to guide the vehicle wheel (18) can be pivotally coupled to the subframe (14), wherein the subframe (14) has at least one deformation area (40) arranged between the attachment points (26, 28) and deformable in the event of an accident impact on the subframe (14), by the deformation of which the first attachment point (26) can be moved from its initial position (42) into a safety position (44).in which the first connection point (27) is arranged closer to the second connection point (28) than in the initial position.

The utility model relates to the technical field of automobile control arm machining, and particularly discloses an automobile suspension control arm shaping assembly which comprises a supporting frame, a fixing frame is installed on the top of the supporting frame, a stamping part is installed at the front end of the fixing frame, and a die base is rotatably installed on one side of the fixing frame. Mold grooves are formed in the upper surface and the lower surface of the mold base correspondingly, a demolding mechanism used for ejecting out workpieces formed in the mold grooves is arranged in the mold base, the demolding mechanism comprises a two-way threaded rod, the two-way threaded rod is rotationally installed in the mold base, and the two sides of the two-way threaded rod are in threaded connection with hinge bases correspondingly; connecting rods are rotationally mounted at the upper end and the lower end of the hinge seat; through the arrangement of the demolding mechanism, the demolding mechanism can be driven while the second motor drives the mold base to turn over, workpieces are ejected out of the mold groove, the workpieces fall into the material collecting box, rapid demolding of the workpieces is achieved, and use of workers is facilitated.

The embodiment of the invention provides an arm support system, an operation system and a control method, the arm support system comprises a folding arm support, the folding arm support comprises a plurality of arm sections, any two adjacent arm sections are rotatably connected, the plurality of arm sections comprise a head end arm section and a tail end arm section, and the tail end arm section is connected with a mechanical arm; the two ends of any first electric cylinder are arranged on the two adjacent arm sections correspondingly, and the first electric cylinders are used for driving the two adjacent arm sections to rotate relatively; the slewing bearing is rotationally connected with one end of the head-end arm section; and the second electric cylinder is arranged on the slewing bearing, and the second electric cylinder is used for driving the head end arm section to expand or retract relative to the slewing bearing. According to the technical scheme, the first electric cylinder and the second electric cylinder are adopted to control the arm section to stretch, and one-key unfolding and folding operation of the arm section is achieved.

A vehicle with driving and steering rear wheels includes a rear suspension system having a support frame mounted on the vehicle body. For each rear wheel, a wheel support is connected to the frame by oscillating arms. An actuator is mounted on the frame, with control rods, protruding from opposite ends of the actuator body, and connected to the wheel supports by control arms. Within a space between the rear wheels, there is a rear motor or differential. The actuator body is mounted on the frame along a transverse direction spaced apart from an axis of the rear wheels to avoid interference with the motor or differential. The control arms are substantially parallel to a transverse direction perpendicular to the longitudinal direction, or form an angle therewith not exceeding 15 degrees. The control rods are connected to the control arms with the interposition of a transmission.

The invention discloses a welding and clamping device for an automobile control arm, and relates to the technical field of automobile manufacturing, the welding and clamping device comprises an operation table, a base is fixedly mounted on the front surface of the operation table, a first control rod is arranged at the top of the base, a welding device is arranged at the bottom of a top cover, and the welding device is electrically connected with the first control rod; the supporting frame is fixedly installed on the top of the operation table, the connecting piece is fixedly installed on the face, close to the shell, of the supporting frame, the fixed disc is fixedly installed at the end, away from the supporting frame, of the connecting piece, and the rotating disc is rotationally installed on the face, away from the connecting piece, of the fixed disc. The sliding table is fixedly mounted on the face, away from the fixed disc, of the rotating disc, the first clamping plate is slidably mounted at the top of the sliding table, the first clamping plate can clamp the control arm, welding failure caused by position deviation of the control arm during welding is prevented, the reject ratio during machining is reduced, and the working efficiency is improved.

The invention belongs to the technical field of swing arm assembling, and particularly relates to an automobile aluminum alloy spherical hinge control arm assembly and a modular assembling method thereof.The automobile aluminum alloy spherical hinge control arm assembly comprises a swing arm body, a ball head assembly is assembled in the tip end of the middle of the swing arm body, and swing arm lining assemblies are assembled in the two ends of the swing arm body; comprising an assembling machine table, and a rotating platform used for fixedly placing a swing arm body is rotationally assembled on the surface of the assembling machine table; the edge of the surface of the assembling machine table is provided with a pre-assembling mechanism used for pre-assembling the ball head assembly into the swing arm body, a press-fitting mechanism used for pressing the ball head assembly into the swing arm body and a lateral press-fitting mechanism used for installing swing arm lining assemblies into the two ends of the swing arm body. On the premise that the direction of the swing arm body does not need to be changed, the lateral press-fitting process is achieved, and assembling of all modules and material supplementing and preassembling work of corresponding parts can be completed at the same time.

The invention relates to a wheel side speed reduction driving integrated assembly coupling kingpin steering and steering trapezoid, and relates to the technical field of automobile wheel side driving suspension assembly angle modules. A wheel-side speed reduction driving integrated assembly coupling kingpin steering and a steering trapezoid comprises a driving motor, a wheel-side speed reducer and a steering knuckle, the upper end and the lower end of the steering knuckle are rotationally connected with an upper control arm and a lower control arm respectively, and the upper end of the steering knuckle is connected with a kingpin steering mechanism. The upper control arm is connected to the kingpin steering mechanism, the kingpin steering mechanism drives the steering knuckle to rotate around the axis of a kingpin, a vertical connecting rod is connected to the upper portion of the lower control arm, the upper end of the vertical connecting rod extends in the longitudinal direction of a vehicle to form a proportional connecting rod, and a spring shock absorber is hinged to the end of the proportional connecting rod. And the middle part of the proportional connecting rod is connected with the vehicle body. The large-angle steering device has the advantages that space layout optimization is achieved, motion interference among all components is avoided, and the large-angle steering effect can be achieved.

The invention belongs to the technical field of assembly equipment, and discloses automobile part assembly equipment which is technically characterized by comprising an equipment frame, a workbench is arranged on the surface of the equipment frame, an assembly seat is fixedly mounted on the surface of the workbench, and a positioning column is fixedly mounted on the surface of the assembly seat; a control arm body is jointly placed on the surfaces of the supporting seat and the assembling seat, a lining is placed above the mounting hole, an alignment mechanism is arranged on the surface of the positioning column and comprises a lining positioning assembly and a control arm positioning assembly, and the lining positioning assembly comprises a push plate, a first positioning part and a first adjusting part. The control arm positioning assembly comprises transverse columns, a second positioning part and a second adjusting part, the second positioning part and the second adjusting part are arranged to be matched with each other, the positions of the multiple sets of transverse columns can be conveniently adjusted, then the positions of the mounting holes can be adjusted, the mounting holes coincide with the central axis of the lining, and the service life of the lining is prolonged. The pushing and pressing column can accurately assemble the lining into the mounting hole.

The invention relates to the technical field of train brake disc assembly, in particular to a tightening device. The invention provides a tightening device which comprises a base, a control arm and a working assembly, the working assembly comprises a first support and a torque gun, the first support is connected with one end of the control arm, the first support is of a stepped structure, a through hole is formed in a step, close to one end of the control arm, of the first support, and the torque gun is installed at the through hole; the torque gun not only can be used for assembling the fastener, but also can be used for semi-automatically disassembling the fastener. The positioning assembly and the torque gun are oppositely arranged, the positioning assembly accurately positions the brake disc before operation, the accuracy of tightening operation of the torque gun is guaranteed, the positioning assembly and the torque gun work cooperatively, it is guaranteed that each bolt can be installed with accurate torque and rotation angle, and brake disc operation faults caused by installation errors are effectively avoided.

The invention discloses a drill rod loading and unloading operation vehicle which comprises a chassis, a cab, a mounting platform, an arm support system and a clamping jaw mechanism. The chassis provides a moving platform and is integrated with an engine and a hydraulic system or a pneumatic system to serve as a power source, the cab is arranged on the chassis, and a walking control system of the whole vehicle and an operation control system of the mechanical arm are arranged in the cab. The arm frame system is installed on an installation platform on the front portion of the chassis, the arm frame system is controlled to work in a hydraulic or pneumatic mode, multiple motion freedom degrees are provided for the clamping jaw mechanism at the tail end of the arm frame system, and the clamping jaw mechanism is installed at the tail end of the arm frame system, composed of a rotary driving mechanism and a clamping mechanism and used for grabbing, positioning and releasing a drill rod. According to the scheme, through a hydraulic or pneumatic driving mode, comprehensive mechanization of drill rod carrying, loading and unloading is achieved, the problems that a manual mode is large in labor intensity, low in efficiency, poor in safety and the like are effectively solved, and the drill rod loading and unloading device has the advantages of being compact in structure, flexible to operate, high in adaptability and low in cost.

The utility model discloses an automobile suspension system. Comprising an angle module mounting plate, an upper control arm, a lower control arm, an air spring and electronic damper CDC assembly, a steering module and a steering knuckle. The top of the steering knuckle is directly connected with a steering module, the upper portion and the lower portion of the steering knuckle are connected with an angle module mounting plate through an upper control arm and a lower control arm respectively, an air spring and an electronic damper CDC assembly are further connected between the lower control arm and the angle module mounting plate, and the steering knuckle is fixedly mounted on a hub structure. And a tire rim and a brake are mounted on the hub structure. The suspension system supports four-wheel independent driving and four-wheel independent steering, is used for achieving the functions of in-situ steering, horizontal transverse moving and the like of the whole vehicle, and achieves ultra-small turning radius, large turning angle, reliable structure and performance and high expansibility during turning.

The present invention belongs to the technical field of assembly equipment and discloses an automobile parts assembly equipment, the technical points of which are: it includes an equipment frame, a workbench is provided on the surface of the equipment frame, an assembly seat is fixedly installed on the surface of the workbench, a positioning column is fixedly installed on the surface of the assembly seat, a control arm body is placed on the surface of the support seat and the assembly seat, a bushing is placed above the mounting hole, an alignment mechanism is provided on the surface of the positioning column, the alignment mechanism includes a bushing positioning assembly and a control arm positioning assembly, the bushing positioning assembly includes a push plate, a first positioning part and a first adjusting part, the control arm positioning assembly includes a cross column, a second positioning part and a second adjusting part, and by arranging the second positioning part and the second adjusting part to cooperate with each other, the position of multiple groups of cross columns can be conveniently adjusted, and then the position of the mounting hole can be adjusted so that the mounting hole and the central axis of the bushing coincide, and the pushing column can accurately assemble the bushing into the mounting hole.

The utility model provides a suspension control arm structure, a suspension structure and an all-terrain vehicle, the suspension control arm structure comprises a ball pin mounting seat, a first control arm, a second control arm and a shock absorber mounting frame, and the first control arm is connected with the ball pin mounting seat; the second control arm is connected with the ball pin mounting seat; the shock absorber mounting frame is arranged on the ball pin mounting base and used for being connected with a shock absorber. Wherein the shock absorber mounting frame and the ball pin mounting seat are integrally formed parts. According to the suspension control arm structure, the technical problem that an existing control arm structure is low in production cost and production efficiency can be solved.

The invention discloses a self-adaptive fastener assembly robot which comprises a rotary table and a mechanical arm, the rotary table is used for limiting a countersunk bolt, the mechanical arm is used for matching a hexagonal nut with the countersunk bolt, and the rotary table comprises a first disc body, a second disc body, a third disc body and a fourth disc body; and the second disc body is arranged at the lower end of the first disc body and used for limiting the countersunk bolt, and the mechanical arm comprises a control arm which can horizontally and obliquely move and is used for toppling the hexagonal nut. The expansion pipe is clamped in the C-shaped clamp to achieve rotation, meanwhile, the control arm is changed from inclination to horizontal, the hexagon nut is matched with the countersunk bolt, machining is completed, the control arm is extruded out by the baffle subsequently, the control arm is controlled from inclination to horizontal and then to one second after inclination, the rotating disc rotates, and the position sensor detects the situation; and the control arm moves for one cycle again, so that the hexagon nut is continuously matched with the countersunk bolt.

The invention discloses an automobile control arm threaded bushing pressing device, and belongs to the technical field of automobile control arm machining, the automobile control arm threaded bushing pressing device comprises a protective metal shell, a control box is arranged on the side face of the protective metal shell, and a supporting mechanism is arranged at the bottom of the protective metal shell; the supporting mechanism comprises a supporting assembly used for limiting and supporting the workpiece and a protection assembly used for being matched with the supporting assembly to limit and intercept the workpiece, and the protection assembly is arranged at the top of the supporting assembly. Through mutual cooperation of multiple structures, the shape of the pressing device can be changed in the workpiece assembling process, the threaded bushing is shielded and protected through deformation of the pressing device, and through mutual cooperation of double anti-flying-collapse structures, flying-collapse workpieces are effectively intercepted; the phenomenon that the threaded bushing flies and collapses in the using process of the pressing device is avoided, and the deformed pressing device can forcibly isolate a worker from a stamping structure.

The invention relates to the technical field of vehicle chassis, and provides a rear suspension structure and a vehicle. The rear suspension structure comprises a rear auxiliary frame; the rear steering knuckles are arranged on the left side and the right side of the rear auxiliary frame; the control arm assemblies are arranged between the rear steering knuckles and the rear auxiliary frame, and each control arm assembly comprises an upper front control arm, an upper rear control arm, a lower front control arm and a lower rear control arm which are connected to the corresponding rear steering knuckle and the rear auxiliary frame; the shock absorbers are arranged on all the rear steering knuckles; each lower rear control arm is provided with one spring; in the front-back direction of the vehicle, the shock absorber is located on the front side of the upper front control arm, and the spring is located between the upper front control arm and the upper rear control arm. Through reasonable layout, the shock absorber and the spring are staggered in the front-back direction of the vehicle, so that the mounting points of the spring and the shock absorber are close to wheels as much as possible, the lever ratio of the shock absorber and the lever ratio of the spring are increased, and the comfort and maneuverability of the vehicle are improved.

A ball joint assembly for control arm. The ball joint assembly has an upper portion with a ball socket and stud centered about a first centerline. A radial extension that is connected to the upper portion supports a mounting body with a second centerline and an outer diameter that fits within an aperture in the control arm. A threaded shaft depends from the mounting body and receives a nut to tighten against the control arm until the first centerline of the ball joint assembly is fixed in a desired position.

The invention discloses an industrial carrying intelligent robot, and relates to the technical field of mechanical arms. The device comprises a base, a bearing arm is rotationally installed on the base, two oppositely-arranged connecting plates are constructed on the bearing arm, a movable arm is rotationally installed on one connecting plate through motor driving, a control arm is rotationally installed on the other connecting plate through motor driving, a lever arm is hinged to the upper end of the movable arm, and the lever arm is hinged to the lower end of the control arm. An arc-shaped connecting rod is hinged between one end of the lever arm and the control arm; the horizontal clamping jaw is installed at the other end of the lever arm in a hinged mode, and a clamping head is always kept to be vertically and downwards arranged. According to the steel plate conveying device, the transfer bearing mechanism is arranged, a steel plate can be transferred into the transfer bearing mechanism through the horizontal clamping jaw, the steel plate is overturned in the transfer bearing mechanism through the overturning mechanism in the transfer bearing mechanism, then the steel plate is moved out through the horizontal clamping jaw and transferred to the other conveying belt, the adaptability of the device is greatly improved, and the flexibility is improved.

A suspension assembly includes an upper control arm, a lower control arm, a damper coupled between the lower control arm and a frame rail, and a roll control cylinder coupled between the lower control arm and the frame rail. The roll control cylinder includes a body defining an internal cavity, a piston movably arranged within internal cavity, and a rod coupled to the piston and extending outwardly from the body. The piston divides the internal cavity into a piston chamber and a rod chamber. The suspension assembly further includes an accumulator in fluid communication with the piston chamber, and a charge supply in fluid communication with the accumulator. The charge supply is configured to selectively change a charge pressure within the accumulator to adjust a roll rate or stiffness defined by the roll control cylinder.

A reverse slapper hydraulic bump stop assembly for use in a vehicle includes an upper mounting bracket for affixing to a frame of a vehicle, a lower mounting bracket, a bell crank movably coupled to the upper mounting bracket, and a hydraulic bump stop assembly comprising a first end and a second end. The bell crank includes a bump surface configured to contact the upper mounting bracket. A first end of the hydraulic bump stop assembly is coupled to the lower mounting bracket, and a second end of the hydraulic bump stop assembly is coupled to the bell crank. The hydraulic bump stop assembly is oriented in a substantially vertical direction, such that directions of force do not need to be in line with lower control arm motion, and the assembly can be adjusted towards a front or rear of a vehicle based on a desired bump effect.

The utility model discloses a control arm bushing structure for an automobile, which belongs to the technical field of control arm bushings and comprises an outer lining pipe, a rubber layer is fixedly connected inside the outer lining pipe, an inner lining pipe is fixedly connected inside the rubber layer, and sealing covers are arranged at the top end and the bottom end of the outer lining pipe. Through cooperation of an external threaded pipe, a special-shaped clamping block, an annular digging groove, a first thread and a special-shaped clamping groove, the external threaded pipe is firstly placed in the annular digging groove, then the external threaded pipe is attached to the first thread, and meanwhile, the special-shaped clamping block enters the annular digging groove along with the external threaded pipe; then rotation is conducted through attachment of a first thread and an external thread pipe, then the special-shaped clamping block descends along with rotation and makes contact with the special-shaped clamping groove while rotating, and finally the special-shaped clamping block and the special-shaped clamping groove are clamped through continuous rotation; therefore, the rubber layer does not contact with air for a long time, so that the service life is not shortened.

The invention discloses a design optimization method and system for a control arm, and particularly relates to the technical field of control arms. The method comprises the following steps: determining an optimization target and constraint conditions, identifying a high-stress region by utilizing finite element analysis, monitoring a dynamic load and a material performance degradation curve by combining a multi-axis sensor, and realizing quantitative evaluation of an optimization result and a real working condition deviation; when the deviation is large, real-time monitoring, feedback correction and dynamic design adjustment are further performed by optimizing a geometric structure and installing an intelligent sensor, so that the reliability and safety of an optimization result under complex loads and extreme working conditions are ensured, the durability and the fatigue resistance of the control arm are remarkably improved, the local failure risk is reduced, and the reliability of the control arm is improved. And finally, the overall safety and the performance stability of the vehicle are improved.