A vibration damping system configured to improve ride quality as well as controllability and stability of a vehicle. The vibration damping system is applied to a vehicle comprising a vehicle body suspension, and a seat suspension including a spring and a damper. The vibration damping system is configured to: estimate acceleration of a sprung seat mass and a resonance frequency when vibrations propagates to the sprung seat mass; calculate a target value of the acceleration of the sprung seat mass; and set a spring constant of the spring and a damping coefficient of the damper to values possible to achieve the target value of the acceleration of the sprung seat mass, before the vibrations propagate to the sprung seat mass.

A method for cancelling seat vibration includes receiving a first accelerometer measurement. The method also includes receiving a second accelerometer measurement. The method also includes determining a counter torque value based on the first accelerometer measurement and the second accelerometer measurement. The method also includes selectively controlling a motor using the counter torque value.

A method for cancelling seat vibration includes receiving, from an accelerometer, a plurality of accelerometer measurements and applying a first filter to the plurality of accelerometer measurements to remove accelerometer measurements of the plurality of accelerometer measurements having a frequency above a first threshold frequency. The method also includes applying a second filter to an output of the first filter to remove accelerometer measurements of the output of the first filter having a frequency above a second threshold frequency and applying a third filter to an output of the second filter to generate an accelerometer measurement output having a center frequency corresponding to a resonant frequency of the vibration of the at least one component of the seat. The method also includes determining an absolute magnitude value of the accelerometer measurement output and selectively controlling a motor based on the absolute magnitude value of the accelerometer measurement output.

A seat bottom assembly including a seat bottom frame having a front side and a back side, a seat plate having a front side and a back side, webbing stitches, and tear away stitches. The back side of the seat plate is coupled to the back side of the seat bottom frame. The webbing straps are coupled to and extending between the front side of the seat bottom frame and the front side of the seat plate, and tear away stitches connect two points of the webbing straps along a longitudinal axis so that the webbing straps are partially looped at locations of the respective tear away stitches. The tear away stitches separate and increase a length of the webbing straps in response to experiencing a threshold load in a direction perpendicular to the seat plate.

Suspension systems and grounds maintenance vehicles incorporating the same are disclosed. The suspension system may include biasing elements or springs that may be adjusted to vary the preload and thus change the spring and dampening characteristics of the suspension system. In some embodiments, the system may include an adjustment mechanism that permits simultaneous adjustment of two springs via a single action. In other embodiments, features adapted to assist an operator with mounting/dismounting the vehicle are disclosed.

A vehicle seat includes: left and right side frames disposed left and right separately from each other; a first support member disposed between the left and right side frames to support an occupant; and left and right second support members joined to left and right sides of the first support member and having left and right outer sides supported by the side frames to support the occupant in conjunction with the first support member. The first support member is a plate-shaped member, and has left and right ischial region through holes formed in positions corresponding to ischial bones of the occupant. The second support members are located at least partially within front and rear limits defined by an expanse of the ischial region through holes.

A suspension seat, including: a lower side member that forms a vehicle lower side of a suspension; an upper side member that forms a vehicle upper side of the suspension, and that is configured to support a vehicle seat body from the vehicle lower side; a suspension link mechanism that includes a vehicle lower side portion coupled to the lower side member and a vehicle upper side portion coupled to the upper side member, and that undergoes displacement so as to displace the upper side member along a vehicle vertical direction; a linear displacement section that is provided at the suspension link mechanism and is configured to undergo linear displacement in conjunction with displacement of the suspension link mechanism; and a locking mechanism that immobilizes the linear displacement section so as to immobilize displacement of the suspension link mechanism.

A vehicle seat having a vehicle seat underbody, comprising: a base plate; a side horizontal suspension; a rolling suspension comprising a rod element rotatably mounted with respect to the side horizontal suspension; a scissors-type frame having a first swing and a second swing, wherein the first swing is connected by a first slide element to the rod element and the second swing is connected by a second slide element to the rod element and the first swing is connected to the first slide element and the second swing is connected to the second slide element; a first element carrier; a lengthwise horizontal suspension; and a first spring element, which is connected on the one hand to the first element carrier and on the other hand to the base plate or one of the swings.

A riding outdoor power equipment vehicle, such as for grounds maintenance, having a chassis including a support area, an operator platform for supporting a rider and supported by the chassis, and a suspension assembly. The suspension assembly is configured to resist movement of the operator platform towards the support area of the chassis and includes a biasing element having a plurality of annular portions. At least two annular portions of the plurality of annular portions are spaced apart from one another when the biasing element is in a default orientation and are moved into engagement with one another upon compression of the biasing element between the operator platform and the support area. Compression of the biasing element provides an initial deflection response that decreases substantially in response to increasing loading being applied to the operator platform.

An electrical track assembly may include a pair of tracks, including a first track including a first conductor, a second track include a second conductor; and a support member configured for connection with, removal from, and movement along the pair of tracks in a first configuration and a second configuration. The support member may include a first support member contact, a second support member contact, an electrical load including a first load contact and a second load contact, and a manual switch assembly configured to selectively electrically connect the first conductor with the first load contact, selectively electrically connect the second conductor with the second load contact, and prevent current flow (i) between the first conductor and the second load contact and (ii) between the second conductor and the first load contact, the manual switch assembly including a blocking element.