Abstract: A computer-implemented method for testing a vehicle system. In the method, data of a digital road map are read in, zones are determined for the digital road map, possible sequences of drives along a road of the digital road map are ascertained as a function of the determined zones, a behavior of the vehicle or of a vehicle system of the vehicle is ascertained in a simulation for at least one of the possible sequences, and it is determined as a function of a comparison of the ascertained behavior with at least one predetermined requirement whether the vehicle system exhibits an error or a weakness.

Abstract: A computer-implemented method for controlling a vehicle. The method includes: data of a digital road map are read in, zones are determined for the digital road map, possible sequences of drives along a road of the digital road map are ascertained as a function of the determined zones, a behavior of the vehicle or of a vehicle system of the vehicle is ascertained in a simulation for at least one of the possible sequences, and the vehicle is controlled in accordance with one of the possible sequences as a function of a comparison of the ascertained behavior with at least one predetermined requirement.

Abstract: An illustrative example method of mapping a physical environment using an occupancy grid containing a set of cells associated with respective occupancy probabilities includes measuring a potential position of an object, using a sensor and identifying a segment representing a distribution interval of probable values associated with respective probability values relating to the measured potential position. The segment extends according to only one of two dimensions of the coordinate system of the sensor and penetrates a subset of potentially occupied cells. The method includes evaluating a probability of occupancy of each potentially occupied cell by determining the features of a segment portion included in the potentially occupied cell, and determining the probability of occupancy of the potentially occupied cell as a function of the determined segment portion using the probability density function.

Abstract: An autonomous vehicle is provided with a touch panel that enables an operator to input vehicle speed control instructions during an automatic driving mode and a mechanical operation unit for inputting driving control instructions. When the driving mode of the autonomous vehicle is the automatic driving mode or a semi-automatic driving mode, a driving control unit of the autonomous vehicle prioritizes a vehicle speed control instruction input from the touch panel over a vehicle speed control instruction input from the mechanical operation unit and executes vehicle speed control for the autonomous vehicle based on the prioritized instruction.

Abstract: A driving control device receives power supply from an accessory battery to operate, controls automatic driving, and outputs a control signal. A steering ECU, a power ECU and a brake ECU instruct a steering mechanism, a PCU and a brake to operate based on the control signal, respectively. An emergency stop switch is operated by an operator. In a case where the emergency stop switch is operated, an interface processing device cuts off a switch to stop the power supply, shuts down the driving control device, and outputs a control signal that causes the steering mechanism, the PCU and the brake to perform an emergency stop operation.

Abstract: An automatic driving vehicle includes a mechanical emergency stop button for operation by an operator. When the operator presses the emergency stop button while the automatic driving vehicle is running in an automatic driving mode, the automatic driving vehicle stops running. The automatic driving vehicle has a touch panel for operation by the operator, the touch panel being provided forward of the emergency stop button. When the operator presses a SLOW DOWN button while the automatic driving mode is running in the automatic driving mode, the automatic driving vehicle decelerates and thereafter continues running.

Abstract: An automatic driving vehicle has an automatic mode to automatically operate along a predetermined travel route in accordance with an operation schedule provided from an operation management center through communication and so as to arrive at a predetermined spot at predetermined time. In a case where the communication is normal, the automatic driving vehicle operates automatically in accordance with the operation schedule provided in the automatic mode through the communication, and in a case where abnormality occurs in the communication, the automatic mode shifts to a semiautomatic mode to operate the automatic driving vehicle in a state where a function of communicating with the operation management center is limited.

Abstract: A method for operating an automated vehicle. A request for the take-over of at least one driving task presently carried out by the automated vehicle is output to a driver of the automated vehicle. Prior to a transfer of the driving task to the driver following the request, at least one measure is carried out, with which at least one function of the automated vehicle, which represents a potential source of distraction for the driver during the transfer of the driving task, is deactivated or reduced.

Abstract: In the cabin of an automatic driving vehicle, a touch panel for inputting a control instruction in relation to the automatic driving vehicle and a display for displaying information on the automatic driving vehicle are provided. The touch panel and the display are disposed in the front end area in the end area in the vehicle width direction inside the cabin of the automatic driving vehicle such that their display surfaces are directed rearward. The touch panel is disposed further outward in the vehicle width direction than the display.

Abstract: A transport system for carrying a proppant, the system comprising a loading tower, a first transfer tower, a second transfer tower and an unloading tower. The loading tower is located proximate a loading area while the unloading tower is located proximate an unloading area. The system also includes a first transfer tower and a second transfer tower. A first aerial cable conveys a transfer container from the loading tower to the first transfer tower, while a second aerial cable conveys the transfer container from the second transfer tower to the unloading tower. The transfer container is configured to be suspended from the first and second aerial cables en route from the loading tower to the unloading area. Sand or supplies from the transfer container is received at the unloading area for use in a wellbore operation. Methods of transporting sand for use in wellbore fracturing operations are also provided.

Abstract: A universal storage device for a wheel chock used in an auto carrier railcar comprises a grating coupled to a backplate. The grating has a regularly spaced array of horizontal rods, including an intermediate horizontal rod with a missing segment that creates a gap in the array. The backplate has a plurality of tabs extending transverse to the horizontal rods that are wrapped around one or more horizontal rods to couple the grating to the backplate. The wheel chock has multiple rows of teeth for engaging the grating. When installed on the storage device, a first row of teeth engages a first horizontal rod of the grating and a second row of teeth is positioned in the gap in the array of horizontal rods. The storage device further comprises a locking flange rotatable between a locked and an unlocked position. In the locked position, the locking flange engages an upper surface of the wheel chock to secure the wheel chock to the storage device.

Abstract: A covered hopper railroad freight car having a car body whose opposite longitudinal sides include substantially flat, parallel, generally vertical upper side wall portions free from outwardly protruding structural strength members.

Abstract: A mixer, which forms the core part of an air-conditioning assembly of a rail vehicle, has two inlets, an outlet, and a central region between the inlets and the outlet. A first inlet is connected to a fresh air supply, and a second inlet is connected to a circulating air supply such that fresh air and circulating air reach the central region, where the circulating air is mixed with the fresh air to obtain supply air. The central region is connected to the fresh air inlet via an opening, which forms a transition region between the fresh air inlet and the central region. The transition region contains a profiled section with a wing-shaped cross-section in the transition region where the supplied fresh air generates negative pressure along the transition region, and the circulating air is suctioned into the central region of the mixer with a boost from the negative pressure.

Abstract: A railway vehicle, a coupler, and a coupler body thereof. The coupler body comprises an upper traction platform, a lower traction platform, a lock chamber, and a pin hole. A traction surface of an upper traction platform and/or a lower traction platform is divided into a contact area and a yielding area along the direction approaching the lock chamber, an extension face of the end of the contact area close to the lock chamber is an M2 face, and the yielding area is positioned at the side of the M2 face close to the pin hole. The yielding area is positioned on the side of the contact area next to the lock chamber and there is a gap and no contact between the yielding area and a traction platform of a coupler knuckle.

Abstract: In one aspect, an apparatus for turning a corner, the apparatus being disposed adjacent to a grounded surface and comprising: a turntable platter, rotatably coupled to the grounded surface, for orienting a line-drawn trolley; a locking mechanism, disposed on the turntable platter, for preventing rotation of the turntable platter with respect to the grounded surface; a first turntable guide, removably coupled to the turntable platter, for guiding a draw line through the line-drawn trolley; a second turntable guide, removably coupled to the turntable platter, for guiding the draw line through the line-drawn trolley; a first stationary diverter, removably coupled to the grounded surface, for diverting the draw line around the line-drawn trolley; and a second stationary diverter, removably coupled to the grounded surface, for diverting the draw line around the line-drawn trolley.

Abstract: A rail and train system has at least a rail pair on which a rail vehicle that is provided with at least one wagon is movable. In the wagon, at least one lifting device is accommodated with which containers can be transported through an opening in the floor of the wagon and which is movable transverse to the length direction of the wagon. The rail vehicle can be provided with a chassis that is formed by two chassis parts that are positioned at a distance behind each other in the travel direction.

Abstract: The present invention relates to a train movement authorization method based on vehicle-to-vehicle cooperation.

Abstract: A system includes one or more processors configured to identify first location data corresponding to a first location of a first vehicle of a vehicle system when the first vehicle passes a reference object and identify second location data corresponding to a second location of a second vehicle of the vehicle system. The one or more processors are further configured to determine whether the first location and the second location are within a predetermined distance of each other and in response to determining that the first and second locations are within the predetermined distance of each other, and generate a signal related to a condition that the first location and the second location are within the predetermined distance.

Abstract: The object of the present invention is to provide a system for operating a marshalling yard in a more efficient and time saving way, by avoiding unnecessary procedures of preparation, usually done manually by mechanical means only, and turn it into an advanced technological facility.

Abstract: Examples includes systems and methods for lifting and moving gondolas using a modular gondola moving system. Components of a modular gondola moving system include interchangeable skates. The interchangeable skates are further removably attached to a longitudinal member which, when connected to the longitudinal member, form a skate system. Multiple skate systems are positioned to the underside of a gondola and may additionally be connected together by connector bars for stabilization and to form the modular gondola moving system. One or more lifting devices are provided independent of and are used in combination with each skate system for positioning the gondola on each skate system. The one or more lifting devices may be repeatedly used in order to place the gondola on a single modular gondola support system.

Abstract: A personal cart and method for using the personal cart. The personal cart has a platform support frame. Wheels are rotatably connected to the platform support frame. Handles are also attached to the platform support frame. A rectangular platform is rigidly connected to the platform support frame. The platform has a raised railing extending upwards along the outer perimeter of the platform. In a preferred embodiment the platform support frame is foldable. Also, in a preferred embodiment a plurality of tote bags is placed on the platform. Each tote bag laterally supports another tote bag and the plurality of tote bags is also laterally supported by the raised railing.

Abstract: The invention relates to an arrangement in an electric vehicle, to at least one wheel of which vehicle an electric motor has been fitted. The electric motor comprises a rotor fitted to be on the outer side and a stator fitted to be on the inner side. The stator of the electric motor is arranged to function as a wheel axis, so that the stator is fitted to bear the loads between said wheel and the remaining structure of the vehicle. Additionally, the arrangement is equipped with an assistance unit, which comprises a motor control unit and a sensor arrangement, which the sensor arrangement is arranged to identify a force directed by an operator to the vehicle, which the vehicle is moveable by the force of the operator, and to produce a sensor signal from it, and which the control unit is arranged to control the operation of the motor based on the sensor signal.

Abstract: Proposed is a baby carriage having improved convenience of use, the baby carriage including a main frame, a seat frame, a storage basket, and a wheel unit, wherein the baby carriage is generally used as a single baby carriage and a seat is detachably coupled to the rear of the single baby carriage such that the single baby carriage is utilized as a twin baby carriage when a second baby is born, and wherein it is possible to carry a pet in the baby carriage irrespective of carrying a baby or an infant in the baby carriage, whereby the baby carriage is used in various forms depending on circumstances of a user or a home.

Abstract: A backrest adjusting mechanism disposed between a backrest tube and a frame of an infant carrier is disclosed. The backrest adjusting mechanism includes an outer cover, an inner cover, a driving member, a locking member, and an operating member. The outer cover is fixed at the frame. The inner cover is connected to the backrest tube and pivoted to the outer cover via a pivot shaft. The driving member is movably disposed between the outer cover and the inner cover. The locking member is movably disposed on the driving member. The operating member is connected to the driving member for driving the driving member to move between a first position and a second position. Switching of the driving member between the first position and the second position drives the locking member to selectively lock or release the outer cover and the inner cover.

Abstract: A locking device is presented for an adjustable steering column assembly for a motor vehicle, comprising an actuating element and a damping device. The damping device has a first damping element and a second damping element, wherein the first damping element is attached to the actuating element and the second damping element is attached to a frame part, wherein the first and/or second damping element relative to the other damping element are rotatably mounted. The first and the second damping element each have a coupling section, wherein the coupling sections are engaged at least over a partial section of a movement of the actuating element, and wherein a relative rotation between the two damping elements is damped by deformation of the first and/or second damping element and/or by friction, at least over a partial section of a movement of the actuating element.

Abstract: A collapsible steering column assembly for a vehicle is provided. The assembly includes a lower jacket. The assembly also includes an upper jacket at least partially received within the lower jacket, the upper jacket telescopingly moveable relative to the lower jacket. The assembly further includes a collapse limiter having an inner strap and an outer strap, the inner strap being at least partially nested within the outer strap, the collapse limiter being moveable with the upper jacket to provide a collapse distance of the collapsible steering column assembly that is constant regardless of a telescopic position of the upper jacket.

Abstract: A steering column may include a casing unit that can be connected to a body of a motor vehicle. A steering spindle may be rotatably mounted in the casing unit about a longitudinal axis. The casing unit may have an inner casing that is received in an outer casing so as to be telescopically adjustable in a direction of the longitudinal axis. A clamping device may be switchable between a fixing position in which it fixes the inner casing relative to the outer casing and a release position in which it allows telescopic adjustment of the inner casing relative to the outer casing. An energy absorption device may include a deformation element arranged between the inner casing and the outer casing. The casing unit may comprise a cable mounting that includes a fastening element for holding a cable and that is at least partly formed as a deformation element.

Abstract: A steer-by-wire steering system for motor vehicles includes an electronically controlled steering actuator acting on steered wheels of the vehicle responsive to a steering demand and a feedback actuator transmitting retroactive effects of the road to a steering wheel, wherein the feedback actuator and the steering actuator have a redundant power supply.

Abstract: A steering wheel actuator is attached to a steering wheel column. The steering wheel actuator includes a gear assembly for turning a steering wheel on the steering wheel column, a motor for rotating the gear assembly, and an enclosure. A control system in the enclosure controls the motor to automatically steer the vehicle. The control system may receive global navigation satellite system (GNSS) signals from a GNSS antenna and GNSS receiver located in the enclosure and automatically steer the vehicle based on the GNSS signals. The control system also may receive inertial measurement unit (IMU) signals from an IMU located in the enclosure and automatically steer the vehicle based on the IMU signals. The control system also may receive user input signals from a user interface located on the enclosure and automatically steer the vehicle based on the user input signals.

Abstract: A steering system shaft bearing assembly having a shaft includes a rotatably mounted about a shaft axis in a housing made of plastic via a rolling bearing. In this case, the rolling bearing is fastened to the housing by means of a fastening ring which cooperates with an internal thread on the housing side and has an external thread. The present disclosure further relates to a steering system for a motor vehicle, comprising such a steering system shaft bearing assembly. Furthermore, a method for producing such a steering system is disclosed.

Abstract: A motor control system includes an inverter, a voltage control calculating a voltage command value indicating a voltage to be applied to a motor from the inverter based on a deviation between the current command value and the actual current detection value, and a torque ripple compensation unit adding a compensation value for compensating a torque ripple in the motor to a signal value on an upstream side in a signal flow that passes through the voltage control unit. The torque ripple compensation unit includes a phase compensator calculating a compensation value component in the voltage control unit based on an actual angular velocity value indicating an angular velocity at which the motor rotates, and an inverse characteristic processor calculating a compensation value component for compensating the torque ripple based on an inverse characteristic of an open loop transfer function in a feedback control.

Abstract: A motor control system includes an inverter and a control calculation unit. The control calculation unit includes a voltage control calculation unit that calculates a voltage command value indicating a voltage to be applied to a motor from the inverter on the basis of a current deviation between the current command value and the actual current detection value, and a compensation calculation unit that compensates at least one of a k-th component and a 1/k-th component in the motor with respect to a signal value on at least one of an upstream side and a downstream side in a signal flow that passes through the voltage control calculation unit. The compensation calculation unit calculates a compensation value on the basis of an actual angular velocity value indicating an angular velocity at which the motor rotates and the target current command value, while also taking into account advance angle control.

Abstract: A connector terminal (40) is formed by a connector joining portion (400) that is joined to a mating connector terminal, a connector bonding portion (40A) that is bent from the connector joining portion (40C) and extends along a surface of a board (31) and a movement stopper portion (40P-C) that engages with a movement stopper part (31E) provided at the board (31) and stops the connector bonding portion (40A) from moving on the surface of the board (31). In a state in which the connector bonding portion (40A) is put on solder applied to the board (31), the movement stopper portion (40P-C) engages with the movement stopper part (31E) of the board (31), and the connector terminal (40) is bonded and fixed to the board (31) with melted solder.

Abstract: A steering axle for steering the wheels on the axle of a four-wheel forklift truck by a hydraulic or electric steering device. The steering axle has an axle beam with first and second wheel carriers. The wheel carriers are arranged pivotably on the axle beam. A steering rod is connected, in articulated fashion, to the two wheel carriers in order to transmit steering movements. A steering actuator produces the steering movement and has an actuator housing. The actuator housing has at least one guide section for the passage of the steering rod through the actuator housing. The steering actuator has at least one sliding bearing device for the radial support of the steering rod on the at least one guide section.

Abstract: A worm gear for a worm gear mechanism of a motor vehicle steering system includes a carrier body and a multiplicity of teeth with tooth surfaces. The teeth point radially outward and the carrier body is formed from a plastic including reinforcement fibers and has a multiplicity of ribs with rib surfaces which point radially outward from a central encircling ring-shaped web of the worm gear. The teeth are applied to the ribs of the carrier body by injection molding, and the reinforcement fibers are oriented, wherein the multiplicity of reinforcement fibers, in terms of their orientation, follow the adjacent rib surfaces of the carrier body and/or the adjacent tooth surfaces of the teeth.

Abstract: A control device for an on-board device including an actuator is configured to: supply power to a first microprocessor and a first driver circuit from a first power source through a first power supply path; supply power to a second microprocessor and a second driver circuit from a second power source through a second power supply path; and use the first and second driver circuits to drive the actuator. In this control device, the negative electrodes of the first and second power sources are electrically connected to a common ground portion. Furthermore, the control device includes a first and second sensor for measuring current or voltage between the vehicle body ground and the negative electrodes of the first and second power source, respectively. When detecting an abnormal current or voltage, the first and second microprocessors control the first and second driver circuits so as to place a limit on power supply to the actuator.

Abstract: A control device for an on-board device including an actuator is configured to: supply power to a first microprocessor and a first driver circuit from a first power source through a first power supply path; supply power to a second microprocessor and a second driver circuit from a second power source through a second power supply path; and use the first and second driver circuits to drive the actuator. In this control device, the negative electrodes of the first and second power sources are electrically connected to a common ground portion. Specifically, the first negative electrode of the first power source and the second negative electrode of the second power source are connected to the common ground portion respectively through independent first and second connector portions.

Abstract: The present invention relates to a method and a system for vehicle steering control comprising controlling a feedback torque actuator (130) in series with an angle overlay actuator (140) in a vehicle steering system (100), where said feedback torque actuator (130) is controlled in such a way that a target feedback torque is achieved and said angle overlay actuator (140) is controlled in such a way that a target overlay angle is achieved. The feedback torque actuator (130) is arranged above said angle overlay actuator (140), i.e.

Abstract: A multidirectional transport vehicle includes a longitudinal axis which defines a longitudinal direction, a transverse axis which defines a transverse direction, a steering system, a driving direction switch, and a driving direction adjustment element. The steering system comprises at least three independently steerable wheels and a steering target value transmitter which steers the wheels. Each wheel has a wheel axle. A steering pole, on which each wheel axle is aligned when cornering, is moved along a steering pole axis by actuating the steering target value transmitter. The driving direction switch includes a limited number of separate switch positions, wherein exactly one switch position preselects exactly one respective rotational position of the steering pole axis relative to the multidirectional transport vehicle and preselects one of two driving directions facilitated thereby. The driving direction adjustment element changes a preselectable rotational position of the steering pole axis.

Abstract: A rack assembly for a vehicle steering system includes a first rack component extending longitudinally from a first outer end to a first inner end, the first rack component having a first shoulder extending radially outwardly from a neck region to a head region. The rack assembly also includes a second rack component extending longitudinally from a second outer end to a second inner end, the second rack component having a second shoulder extending radially outwardly from a neck region to a head region. The rack assembly further includes a coupling assembly having an inner surface defining a hollow region that the head region of the first rack component and the head region of the second rack component are each disposed within, the inner surface having a first radial protrusion in abutment with the first shoulder and a second radial protrusion in abutment with the second shoulder.

Abstract: A vehicular trailering assist system for a vehicle includes a camera disposed at a rear portion of a vehicle and having a field of view exterior and at least rearward of the vehicle, the field of view encompassing at least a portion of a trailer hitched to the vehicle. A control includes a processor for processing image data captured by the camera and sensor data captured by a steering wheel angle sensor and a wheel RPM sensor. The control determines a trailer angle of the trailer relative to the vehicle, a steering wheel angle, and a wheel RPM of a wheel of the vehicle. The control estimates a trailer beam length based on at least the determined trailer angle, the determined steering wheel angle, and the determined wheel RPM.

Abstract: A steering apparatus according to an aspect of the present disclosure includes a rim member, a center member connected to a steering shaft at a rotation center of the rim member, a first sound output apparatus provided on a front surface of the rim member or the center member, and a first rim chamber unit provided in the rim member and in communication with a space behind the first sound output apparatus.

Abstract: A method in a data processing system including at least one processor and at least one memory including instructions executed by the at least one processor to implement a lane change system is provided by the present disclosure. The method includes receiving, from at least one of a plurality of sensors coupled to a vehicle, information associated with a location of an object longitudinally ahead of the vehicle, determining a sequence of control inputs associated with a time horizon to avoid a collision between the vehicle and the object based on a constraint and the location of the object, and the determining the sequence of control inputs including minimizing a maximum tire slip angle of the vehicle during the time horizon subject to the constraint, and causing a vehicle control system of the vehicle to perform a vehicle maneuver based on the sequence of control inputs.

Abstract: A vehicle includes: a sensor configured to detect an obstacle of a front side of the vehicle to obtain at least one of position information or speed information of the obstacle; a lane detector configured to detect a lane on which the vehicle is located; and a controller configured to calculate a first lateral movement distance for the vehicle to avoid an obstacle through steering, to determine a steering-based avoidance path for the obstacle based on the first lateral movement distance, to determine whether to depart the lane on the steering-based avoidance path, and to control the vehicle to perform steering avoidance control when the vehicle does not depart the lane.

Abstract: A suspension member includes a cross member and front body mounts. The cross member includes a main panel including a lower panel and an upper panel joined together, and a reinforcing panel joined to the main panel. The cross member is a member including a front wall, an upper wall, a rear wall, and a lower wall, and having a closed sectional shape defined by the front wall, the upper wall, the rear wall, and the lower wall. The reinforcing panel includes a lower flange constituting a front portion of the lower wall, and an intermediate wall extending upward from a rear end of the lower flange and joined to the upper wall. On opposite sides of the cross member in a vehicle-width direction, bottom walls of the front body mounts are joined to the flange, and side walls of the front body mounts are joined to the main panel.

Abstract: The frame of a vehicle includes side rails disposed on the respective left and right sides of the vehicle and extending along the longitudinal direction of the vehicle, a lower cross member connected to the end portions of the side rails and extending along the lateral direction of the vehicle, an upper cross member positioned above the lower cross member and extending parallel to the lower cross member, vertical members extending in the vertical direction of the vehicle on the respective both end portions of the lower cross member and of the upper cross member, to be connected to the lower cross member and the upper cross member; and side members connected to the upper cross member, and extending on the respective right and left sides of the vehicle from the upper cross member to a side opposite from the side rails along the longitudinal direction of the vehicle.

Abstract: Provided is a vehicle lower-part structure including a pair of center side members arranged under a floor of a vehicle; a first cross member and a second cross member connecting the pair of center side members; a main battery arranged in an underfloor space; one or more support plates arranged at a corner of the underfloor space; and a water tank placed on the support plate, in which the support plate is connected to both the center side member and the first or second cross member and connects the two.

Abstract: On both sides under a floor of an electric vehicle, side members are provided, each in a closed cross sectional shape. Collars and the like are provided in the side members. On a lower side of a lower wall of each of the side members, cross members which are fixed by using the collars or the like are provided. Between the side members on both sides, a main battery is provided and supported by the cross members. In the vicinity of a lower side of a doorway of the electric vehicle, a cutout part is formed such that a height of a portion of an upper wall of the side member is relatively lowered. On an upper surface of the cutout part, a reinforcing member is provided. A ramp passes through a space on an upper side of the cutout part.

Abstract: A vehicle frame structure includes a pair of rear side members extending along a length of a vehicle in a lower part of the vehicle, and a first cross member coupling the pair of rear side members. The first cross member includes an intermediate member and a pair of coupling members. The intermediate member extends along a width of the vehicle at a location further downward with respect to the rear side members and is located under a motor unit. The pair of coupling members respectively extend downward or diagonally downward from the respective side members toward the opposite ends of the intermediate member.

Abstract: A vehicle structure of a frame vehicle includes a central frame portion, a front-side frame portion, and a rear-side frame portion as a frame. A first section of the front-side frame portion from a connecting portion (a rear end portion) to a central frame portion through a portion supporting a front suspension, and a second section of the rear-side frame portion from a connecting portion (a front end portion) to the central frame portion through a portion supporting a rear suspension are formed so as to be symmetrical to each other in the front-rear direction with respect to the central frame portion. The front and rear suspensions are attached to the front-side and rear-side frame portions, respectively, so that the front and rear suspensions are symmetrical to each other in the front-rear direction with respect to the central frame portion.