Abstract: A vehicle recovery board including an inner layer fabricated from a first material, the inner layer including a first face and an opposed second face, in which the first face and the second face each include a plurality of inner layer projections extending outwardly therefrom; and an outer layer fabricated from a second material, the outer layer is configured to substantially overlie the first face and the second face of the inner layer, in which the outer layer includes a plurality of outer layer projections extending outwardly therefrom, in which at least a portion of the plurality of outer layer projections are formed over at least a portion of the inner layer projections.

Abstract: A wheel traction device is adapted for providing traction for a wheel of a vehicle to escape from a mud ground during rotation of the wheel, and includes: a guiding unit having a guiding portion adapted to abut against the wheel; a bearing unit that is detachably connected to the guiding unit, and that has a bearing portion adapted to be positioned on the mud ground such that, during rotation of the wheel, the bearing unit and the guiding unit are prevented from being driven by the rotation of the wheel to move relative to the mud ground, thereby allowing the wheel to roll over the bearing portion under guidance of the guiding portion; and a fastening unit that detachably fastens the bearing and guiding units together.

Abstract: A vehicle wheel traction assembly for use in freeing a stuck vehicle includes a plate having a plurality of ridges engaged thereto and extending from a first face thereof. A second face of the plate can be positioned upon a surface proximate to a drive wheel of a vehicle to increase traction of the drive wheel relative to that of the drive wheel directly upon the surface. A handle is engaged by a pivot pin to the second face of the plate proximate to a first end thereof. The pivot pin is biased toward a first terminus of the handle. The handle is rotatable between a deployed configuration, wherein a second terminus of the handle is positioned distal from the plate, and a stowed configuration, wherein the handle extends between the first end and a second end of the plate.

Abstract: This disclosure details motor vehicles equipped with vehicle exterior components. One or more of the vehicle exterior components can be used both for their primary function when attached to the vehicle and for use as sand ladders when removed from the vehicle. In the first configuration, the vehicle exterior components may be configured as running boards, hood vents, grill inserts, bumper inserts, tailgate inserts, and/or door beams, etc.

Abstract: Structures and methods for controlling road temperature over an underpass space are disclosed, including a structure comprising: footings underlying the road supporting a support assembly comprising: an inner shell; a plurality of beams surmounting the inner shell; an insulating material for thermally isolating the road and the remainder of the support assembly from the underpass space; an outer shell; a temperature control assembly; temperature sensors disposed in the road and the support assembly; and a computer processor configured to receive temperature and weather forecast data; predict changes to the temperature of the support assembly and the road based on the temperature and forecast data; and control the application or removal of heat to the support assembly, based on the predicted changes to the temperature of the support assembly and the road, resulting in the road maintaining a temperature within a predetermined range.

Abstract: A system for cleaning tires of a vehicle traveling along a longitudinal direction over the system includes modular tire cleaning units with debris removal elements. Each unit includes debris removal elements, such as a first chain assembly supported between supports and over a substrate and extending substantially transverse to the longitudinal direction, the first chain assembly defining a first tire track. A second chain assembly is supported between second sets of supports and over the substrate and extending substantially transverse to the longitudinal direction, the second chain assembly defining a second tire track parallel and spaced apart from the first tire channel. The system may include a second modular tire cleaning unit with longitudinally extending chains and/or a trough holding water and/or sprayers at the side of the system.

Abstract: A removably attachable fender flare system has an inner flare and an upper flare and a lower flare, which are removably attachable to the inner flare. The upper and lower flare may have traction protrusions to provide traction to free a stuck off-road vehicle. The inner flare may be in direct contact with and coupled to the off-road vehicle, providing a location to secure the upper and lower flares. The upper flare and lower flare may couple to a groove, which runs the length of the inner flare, from front to back. Further, the lower flare may couple to the upper flare, securing the fender flares.

Abstract: A vehicle recovery device (10) comprising a first track (12) formed from a plurality of pivotally connected panels (14) and a second track (13) formed from a plurality of pivotally connected panels (14). The first and second tracks (12, 13) are moveable from a planar configuration, in which the first and second tracks (12, 13) are usable for vehicle recovery, to a folded configuration, in which the first and second tracks (12, 13) are connectable by connectors (22) to form side walls of a receptacle (11) in the shape of a polyhedron.

Abstract: A vehicular ladder including a body comprising a first plastic and one or more first teeth arranged on the body, wherein the one or more first teeth include a second plastic that is different to the first plastic, and the body is moulded around portions of the one or more first teeth.

Abstract: A vehicle traction mat for use to extricate a vehicle stuck on a slippery road surface is provided. The traction mat comprises at least a main mat segment having a plurality of surface cleats, knobs, and knob cleats on a road-facing surface thereof. The cleats and knobs provide traction between the traction mat and the slippery surface. The traction mat may be provided with edge mat segments foldably connected to opposite ends of the main mat segment. The traction mat may have cleats, knobs, and knob cleats on the tire-facing surface thereof.

Abstract: A floor mat (1) at a standing workstation with a mat surface (4) is disclosed, which comprises a mat structure (2) made of an elastomer material and formed beneath the mat surface (4), in which irregularly distributed elements (3) are arranged, the consistency of which is harder than the consistency of the elastomer material of the mat structure (2).

Abstract: A vehicle recovery ladder includes a body and traction members fastened to the body. Advantageously, in one embodiment any damaged traction members may be readily released and replaced to maintain the performance of the ladder. The traction members may be fastened to the body during forming of the body, Advantageously, the traction members are releaseably fastened to the body.

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a removable center jack mechanism. The first and second plates can extend to a partially-opened or fully-opened position forming a ramp and traction mat platform. The removable center jack mechanism attaches to first plate and second plate via pins. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: A kit that may include an interfacing device that includes pool sidewall interface, and a pool cleaning robot that includes a housing and a drive system. The drive system may include a drive motor system, a group of interfacing modules and a transmission system that is arranged to mechanically couple the drive motor system to the group of interfacing modules. At least one interfacing module of the group may include protuberances that are shaped to fit a non-smooth surface of the pool sidewall interface.

Abstract: A tire traction device can include a strap configured to extend around at least a portion of a vehicle tire; and a traction plate. The traction plate can have a lower surface adapted to sit on a circumferential portion of the vehicle tire, an upper surface opposite to the lower surface, a channel configured to receive the strap, and one or more paddles extending upward from the upper surface. Other features, embodiments, and kits, and related methods are also described.

Abstract: The invention relates to a roll-up traction mat (10) for a vehicle (V) having at least one wheel (R1), said traction mat comprising a main track portion (12), and a track starter tab (20) that is fastened to one of the ends of the main track portion (12) by a hinge-forming connection portion (22) arranged to lower the track starter tab relative to the main track portion, by means of which the track starter tab can be positioned at the bottom of a rut (O) in which said wheel of the vehicle is stuck. The track starter tab comprising a plurality of transverse stiffener elements and a top face provided with studs. The track starter tab and the main track portion are constituted by at least one textile layer covered in a polymer layer.

Abstract: A traction device providing increased traction of a tire having a shape and being on a poor tractional surface, and widening under, and cupping to the shape of, the tire by compression to increase surface area engaging the poor tractional surface to increase weight distribution and the increased traction of the tire. The traction device includes a base and a top cover. The top cover is affixed to the base, and widens under, and cups to the shape of, the tire by the compression to increase the surface area engaging the poor tractional surface to increase the weight distribution and the increased traction of the tire on the poor tractional surface.

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a removable center jack mechanism. The first and second plates can extend to a partially-opened or fully-opened position forming a ramp and traction mat platform. The removable center jack mechanism attaches to first plate and second plate via pins. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: A tire traction device which may improve or provide tire traction for various vehicles is described. The tire traction device includes a board having a first end and a second end, wherein the first end has a curved edge and the second end has a slanted edge. The board may include more than one section. The board includes a rough or grooved top surface, and a plurality of spikes extend from the bottom surface of the board. The tire traction device may also include a flexible component attached to the board. The flexible component is designed so that it may be drawn underneath a spinning tire.

Abstract: Procedure for the manufacturing of pieces for the formation of a removable floor covering and the covering obtained includes obtaining by molding a joint made of a polymer material (1) that is mounted on the contour of a resistant plate (4). On the back of the plate is molded, inside a mold, and by an elastomer material, a layer (15) of shock-absorbing material provided with nerves (16) and conformations (18) on its free surface for the coupling of the intermediate joining elements between the covering pieces.

Abstract: A tire traction device having a tire arm about the width of a tire, roughly conforming the radial curvature of the tire and removably secured thereto, a spring-loaded shock pivotably attached to one end of the tire arm, and a traction track pivotably connected to opposite end of shock. The track includes a series of successively interconnected frames that pivot about each other, the first frame adjacent to the arm and pivotably connected thereto includes a tapered end. In use, the arm is placed about the tire and the tapered end of the first frame is wedged between the tire and the tractionless surface, the remaining frames can be laid flat or staggered. Upon rotation of the tire, the arm is rotated thereabout until releasing after contact with the first frame, whereby instantaneously the first frame and successive frames form a flat traction surface for the tire to rotate about.

Abstract: The present invention provides a surface covering for enabling a surface, e.g. of the uneven, muddy, marshy, or sandy ground type, to be crossed by a vehicle, said surface covering including a double-ply textile core having two covered faces, each covered with at least one polymer layer, and a plurality of through tubular pockets extending substantially transversely through the thickness of the core between the two layers, and enabling respective stiffener bars to be inserted into each tubular pocket so as to make it possible, in particular, to increase the drivability and the load-bearing capacity of the surface when the surface covering is positioned on said surface.

Abstract: A tire traction device having a tire arm about the width of a tire, roughly conforming the radial curvature of the tire and removably secured thereto, a spring-loaded shock pivotably attached to one end of the tire arm, and a traction track pivotably connected to opposite end of shock. The track includes a series of successively interconnected frames that pivot about each other, the first frame adjacent to the arm and pivotably connected thereto includes a tapered end. In use, the arm is placed about the tire and the tapered end of the first frame is wedged between the tire and the tractionless surface, the remaining frames can be laid flat or staggered. Upon rotation of the tire, the arm is rotated thereabout until releasing after contact with the first frame, whereby instantaneously the first frame and successive frames form a flat traction surface for the tire to rotate about.

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a jack. The first and second plates can extend to a partially-opened or fully-opened position, forming a ramp and traction mat platform. The extended traction jack can be placed in front of or behind a vehicle's tire to provide addition traction. A jack extends from at least one plate of the vehicle traction jack to raise a vehicle for repairs to the vehicle's tire. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: A traction mat for extricating the wheels of a vehicle in slippery road conditions comprising: a handle, a plurality of bars with protrusions to provide traction, and a wire connecting the handle and the bars together.

Abstract: A vehicle extraction device includes a track for insertion between a wheel of the vehicle and soft ground below the wheel. A ground-penetration head is connected to a leading end of the traction track. The ground-penetration head includes a plate for placement on an outer perimeter surface of the wheel and a fastening mechanism for attaching the plate to the wheel. Attaching the ground-penetration head to the wheel with the leading end facing an intended direction of rotation of the wheel and rotation of the wheel in the intended direction may insert the ground-penetration head and the track between the outer perimeter surface and the soft ground.

Abstract: A traction mat for extricating the wheels of a vehicle in slippery road conditions comprising: a handle, a plurality of bars with protrusions to provide traction, and a wire connecting the handle and the bars together

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a jack. The first and second plates can extend to a partially-opened or fully-opened position, forming a ramp and traction mat platform. The extended traction jack can be placed in front of or behind a vehicle's tire to provide addition traction. A jack extends from at least one plate of the vehicle traction jack to raise a vehicle for repairs to the vehicle's tire. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: Device that uses the force of one or several persons to help a stuck vehicle get free. It comprises a set of chains of blocks (2) to put in front of the wheels and that are connected by straps (3.6) to a system that will pull them under the wheels while pushing the car by reaction. The forces come from a lever system consisting of a main bar with a triangular part fixed underneath and near its front end. When the operator lifts the bar, the displacement of the extremities of the triangular part away from the wheels creates a pull on the straps while the front end of the bar pushes the car. The blocks become the fulcrum of this lever system. Alternately, a winch fixed on the car bumper pulls on the straps via deviation rollers or rings, transmitting the reaction pushing forces to the car rear part.

Abstract: A vehicle traction mat may include a flexible and unitary body having a central portion. A first and second ramp may be connected to axially opposed first and second ends of the central portion. A tread layer may be positioned on a top surface of the central portion and terminating prior to reaching the first and second ramps. A plurality of first studs may be statically attached to a top surface of the body and protruding upwardly from the central portion such that a top most tip of each of the first studs penetrates out through the tread layer and terminates above the tread layer. A plurality of second studs may be statically attached to the central portion and protruding downwardly therefrom. The body may be selectively rolled and unrolled between cylindrical and planar shapes during non-operating and operating conditions respectively.

Abstract: Disclosed herein are an anti-skid mats for facilitating movement of a vehicle on a slippery surface such as ice, snow, including deep friable snow, and the like, and a method of manufacturing thereof. Disclosed is a method for manufacturing an anti-skid mat's material. Presented an anti-skid mats have a dual function: a function of a means for facilitating movement of a vehicle on a slippery surface and a function of a cars' bumper's protector.

Abstract: A tire traction device which may improve or provide tire traction for various vehicles is described. The tire traction device includes a board having a first end and a second end, wherein the first end has a curved edge and the second end has a slanted edge. The board may include more than one section. The board includes a rough or grooved top surface, and a plurality of spikes extend from the bottom surface of the board. The tire traction device may also include a flexible component attached to the board. The flexible component is designed so that it may be drawn underneath a spinning tire.

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a jack. The first and second plates can extend to a partially-opened or fully-opened position, forming a ramp and traction mat platform. The extended traction jack can be placed in front of or behind a vehicle's tire to provide addition traction. A jack extends from at least one plate of the vehicle traction jack to raise a vehicle for repairs to the vehicle's tire. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: A lightweight vehicle ladder for the recovery and traction of vehicles includes a central recessed portion (48) bordered by longitudinal strengthening ribs (56) and ramps (55) at either end. A plurality of traction members (52), each of which terminates in an upper tire engagement member (54) are disposed within the recessed portion and thereby somewhat protected from the ingress of mud during use in order that traction may be maintained. The underside and topside of the vehicle are formed with complementary shapes in order that a number of the ladders may be stacked one on top of the other to form a laminate of increased strength for application with particularly heavy vehicles.

Abstract: A device for providing traction for a tire of a vehicle includes a pad which is fabricated from non-woven fibers which include an abrasive material. When the pad is placed in abutting relationship with the tire and a slippery surface of snow and/or ice, the abrasive material enhancing friction between said pad and the tire. Because the pad has an open non-woven construction, the snow or ice penetrates the pad and tends to hold it in place. In an embodiment of the invention, one end of the pad is convex and the opposite end is concave.

Abstract: A foldable vehicle wheel traction apparatus is disclosed that includes four traction devices having a regular lattice structure. Each traction device is hingeably connected one to the other to permit the traction devices to be folded one on another with easy storage. The hingeable apparatus connected the traction devices permit minimal lateral movement, which allows the traction devices to be more easily maneuvered when being put in use. The ability of the traction apparatus to support the weight of the wheel is enhanced by the regular lattice structure of each traction device formed by the traction devices elongated lateral members and elongated cross members. In one embodiment, the cross members are composed of, or coated with materials that heat up when the vehicle wheel contacts and spins on the cross member, thereby promoting melting of snow or ice.

Abstract: A tire traction device which may improve or provide tire traction for various vehicles is described. The tire traction device includes a board having a first end and a second end, wherein the first end has a curved edge and the second end has a slanted edge. The board may include more than one section. The board includes a rough top surface, and a plurality of spikes extend from the bottom surface of the board. The tire traction device may also include a flexible component attached to the board. The flexible component is designed so that it may be drawn underneath a spinning tire.

Abstract: A foldable vehicle wheel traction apparatus is disclosed that includes four traction devices having a regular lattice structure. Each traction device is hingeably connected one to the other to permit the traction devices to be folded one on another with easy storage. The hingeable apparatus connected the traction devices permit minimal lateral movement, which allows the traction devices to be more easily maneuvered when being put in use. The ability of the traction apparatus to support the weight of the wheel is enhanced by the regular lattice structure of each traction device formed by the traction devices elongated lateral members and elongated cross members. In one embodiment, the cross members are composed of, or coated with materials that heat up when the vehicle wheel contacts and spins on the cross member, thereby promoting melting of snow or ice.

Abstract: A vehicle traction jack that functions as a traction mat platform, ramp, and vehicle jack to assist a vehicle's tire when a tire is stuck in a rut, hole, or some sort of terrain or weather condition such as sand, gravel, dirt, mud, or snow is disclosed. The traction jack comprises a first plate and second plate, a hinge assembly, and a jack. The first and second plates can extend to a partially-opened or fully-opened position, forming a ramp and traction mat platform. The extended traction jack can be placed in front of or behind a vehicle's tire to provide addition traction. A jack extends from at least one plate of the vehicle traction jack to raise a vehicle for repairs to the vehicle's tire. Easily stored in a vehicle at all times, a single user can use the traction jack to help move any type of vehicle's tire.

Abstract: Disclosed is an inflatable cushion configured with a substantially flattened tubular shape such that in an inflated state the inflatable cushion is highly adaptable so as to readily conform to the terrain of the underlying surface on which it is deployed and to the footprint of the vehicle tire as the vehicle is driven across the device. During typical use the cushion is not fully inflated and operational inflation pressure is generally less than 10 PSI and preferably 5 PSI. For use the cushion is deployed such that the central axis of the tube is substantially parallel to the driving direction of the vehicle. The inflatable automotive traction recovery tool of the present invention simultaneously lifts the vehicle and provides a driving surface with sufficient pressure against the tire and underlying surface to allow the vehicle to drive on it.

Abstract: An auto creeper tread has the following features: three or four rows of circular holes disposed in an orderly manner on a skid-proof pad, wherein, the edge of each of the circular holes protrudes outwards; two rows of rectangular holes disposed on two sides of the skid-proof pad; two protruding reinforcing grooves disposed in the middle of the skid-proof pad; a row of small circular holes disposed on each of the two ends of the skid-proof pad; a track connected to the skid-proof pad by rivets; and a tire lock connected to one end of the track with a clamping plate. The auto creeper tread is designed to provide anti-sink and anti-skid solutions for automobiles.

Abstract: Disclosed is an inflatable cushion configured with a substantially flattened tubular shape such that in an inflated state the inflatable cushion is highly adaptable so as to readily conform to the terrain of the underlying surface on which it is deployed and to the footprint of the vehicle tire as the vehicle is driven across the device. During typical use the cushion is not fully inflated and operational inflation pressure is generally less than 10 PSI and preferably 5 PSI. For use the cushion is deployed such that the central axis of the tube is substantially parallel to the driving direction of the vehicle. The inflatable automotive traction recovery tool of the present invention simultaneously lifts the vehicle and provides a driving surface with sufficient pressure against the tire and underlying surface to allow the vehicle to drive on it.

Abstract: A traction aid for providing traction to a wheel of a vehicle relative a ground surface has two sections, composed of side members and traction members, connected by a connecting mechanism enabling pivotal unfolding and folding of sections between folded and unfolded configurations for device. In unfolded configuration, sections are longitudinally opposed end-to-end to allow wheel to pass over both sections when device is deployed on ground surface. In folded configuration, sections are folded together and extend substantially parallel one another. Each section has a plurality of gripping members attached to side members and extending therefrom.

Abstract: An inventive traction device is provided for extricating mired vehicles from mud, snow or sand. The device is comprised of modules linked together to create a track upon which a mired vehicle drives over. The individual modules each have four walls forming a trough and a number of tire supports which rise up from the floor of the trough. The trough-like construction of the device helps prevent the device from becoming overloaded with mud deposited from mired vehicle tires.

Abstract: Terrain often hinders wheeled vehicles as cars mire in sand and wheeled carts in mud. Beaches, sandy playgrounds, and mud inhibit travel of wheelchairs. A reinforced mat upon a lattice of projections provides a stable surface for wheels and wheelchairs. The projections engage the terrain as the wheelchairs cross the mat toward a destination. Also, the projections take the form of spikes or hollow tubes, the mat has porosity or spaghetti like fibers, and the lattice has various patterns. The reinforced mat may be used with larger vehicles over a variety of terrain.

Abstract: This invention provides a housing (60) for a weight sensor (10). The housing (60) is made from fluid-impervious material and is shaped and configured to completely enclose the weight sensor (10) in a fluid tight manner. The housing (60) includes a bottom portion in the form of a weight sensor accessory pad (62). The pad (62) includes a grooved lower surface (64), the grooves (66) being configured to enhance dispersion, in use, of fluids trapped between the pad (62) and a surface on which the pad (62) rests when a downward force is applied to the part (62).

Abstract: A method for shaking vehicles comprises driving them over a series of appropriately spaced-apart, mutually parallel bars to vigorously shake the wheels, undercarriage, and body to free them of dirt, gravel and debris. An apparatus may have bars with the appropriate spacing. A track may include a frame and the spaced-apart bars may form part of the frame. The track may be large enough to accommodate all the wheels of a vehicle at once. Alternatively, smaller tracks may be flexibly connected end-to-end to form a shaker that will receive right and left hand wheels of the vehicle on respective rows. The shaker may be deployed onto a bed of aggregate that is sufficiently coarse to allow the fallen dirt to sift or be washed through the bed of aggregate. The aggregate may also assist in holding the shaker in place and may provide ramps at the ends of the shaker.

Abstract: A trackhoe anti-skid device for reducing lawn damage having a bottom traction plate a spike connected to the bottom traction plate for frictionally engaging conventional earth. A top traction plate boltable to the bottom traction plate for adjusting the width.

Abstract: A hitch assisting device and method includes a generally planar member having an upper surface and a bottom surface. The planar member has a front edge and a back edge. The upper surface has at least one depression positioned therein. The depression extends between a pair of side edges of the planar member. The tire of the vehicle is positioned in the at least one depression and the trailer unhitched from the vehicle. Thereafter the trailer is aligned with the vehicle when the tire is again positioned in the depression.

Abstract: A method for shaking vehicles comprising driving them over a series of appropriately spaced-apart, mutually parallel bars to vigorously shake the wheels, undercarriage, and body to free them of dirt, gravel and debris. The apparatus provides bars with the appropriate spacing secured to a frame that is sized to be manipulated by hand by construction workers. A track comprises a frame and the spaced-apart bars attached to the frame. Tracks are flexibly connected end-to-end to form rows and rows are laid in a spaced-apart, mutually parallel configuration to form a shaker that will receive the vehicle to be shaken. The shaker may be deployed onto a bed of aggregate that is sufficiently coarse and open-graded to allow the fallen dirt to sift or be washed through the bed of aggregate. The aggregate may also assist in holding the shaker in place and may provide ramps at the ends of each row.