Systems and methods for controlling the speed and direction of vehicles such as tractors.

Each zero turning radius mower steering lever module includes a one-piece plastic housing independently mounted on a grass mowing machine frame member. A central passage extends through each housing, and a steering arm bracket may be positioned in the central passage and pivotably mounted on a horizontal pivot axis. A steering arm may be attached to an upper end of the steering arm bracket, and a hydrostatic transmission linkage and a damper linkage attached to a lower end of the bracket.

Systems for controlling the speed and direction of vehicles such as tractors, including vehicles that have low to zero turning radius capability. Systems include steering and speed coordination systems that control the direction and speed of rotation of vehicle drive units.

A gang reel mower has a hybrid engine, generator and battery pack electric power system driving a pair of electric wheel motors for propelling the mower and for driving individual reel motors for powering a plurality of reel cutting units. A master controller is programmable with a selected clip and maintains the selected clip whether the mower travels straight ahead or is turning. The output power of the generator is damped and is gradually increased during high electrical loads to prevent step responses in the engine and thereby limit engine droop. During regenerative braking of the mower, the generator can be driven as a motor to use the engine as a load. This limits the voltage produced by the traction motors during regenerative braking from damaging the electrical system or overcharging the battery pack. Moreover, maximum transport and mowing ground speeds are automatically reduced during some turns of the mower.

A riding lawn care vehicle includes a frame to which at least a first and second drive wheels are attachable. The vehicle further includes a brake assembly operably coupled to the first and second drive wheels to enable brakes to be selectively applied to the first and second drive wheels. The riding lawn care vehicle also includes a steering assembly with first and second steering levers. First and second steering levers are operably coupled to first and second drive wheels respectively to facilitate turning of the riding lawn care vehicle based on drive speed control of the first and second drive wheels responsive to positioning of first and second steering levers. First and second steering levers are also operably coupled to the brake assembly to activate the brake assembly in response to one of the first or second steering levers being rotated about a vertical axis of the respective lever.

A riding lawn care vehicle may include a frame, a steering assembly, a first brake assembly, and a first biasing assembly. A first drive wheel and a second drive wheel of the riding lawn care vehicle are operably coupled to the frame. The steering assembly includes a first steering lever and a second steering lever. The first and second steering levers are operably coupled to corresponding ones of the first and second drive wheels via a first hydraulic motor and a second hydraulic motor, respectively, to facilitate turning of the riding lawn care vehicle based on drive speed control of the first and second drive wheels responsive to positioning of the first and second steering levers to control the first and second hydraulic motors. The first brake assembly is operably coupled to the first hydraulic motor to enable a braking force to be selectively applied to a motor shaft of the first hydraulic motor responsive to movement of the first steering lever from an inboard position to an outboard position. The first biasing assembly is configured to positively assist movement of the first steering lever between the inboard and outboard positions in both directions.

A gang reel mower has a hybrid engine, generator and battery pack electric power system driving a pair of electric wheel motors for propelling the mower and for driving individual reel motors for powering a plurality of reel cutting units. A master controller is programmable with a selected clip and maintains the selected clip whether the mower travels straight ahead or is turning. The output power of the generator is damped and is gradually increased during high electrical loads to prevent step responses in the engine and thereby limit engine droop. During regenerative braking of the mower, the generator can be driven as a motor to use the engine as a load. This limits the voltage produced by the traction motors during regenerative braking from damaging the electrical system or overcharging the battery pack. Moreover, maximum transport and mowing ground speeds are automatically reduced during some turns of the mower.

An agricultural vehicle is disclosed having a frame with substantially parallel first and second spaced apart side rails extending substantially the length of the frame. First and second cross members extend between said spaced apart side rails in spaced apart relation to each other. The first cross member is equipped with at least one wheel pivotally attached thereto. The second cross member is attached at substantially the rear portion of said frame. The second cross member has two drive wheels rotatably attached thereto and a drive unit mounted on said chassis at said rear portion and independently drivably connected to each drive wheel. First and second drive unit controllers are mounted on different side rails substantially proximal to the front portion of said frame and operable by an operator seated in an operator seat mounted to the frame.

A vehicle gear-shifting control apparatus is equipped with an engine, a motor, an automatic transmission, a friction brake system, and a controller which executes, during deceleration of a vehicle during which the friction brake system is distributing a braking force to front and rear wheels, a regeneration control of imparting a regenerative braking torque to the rear wheels by causing the motor to perform a regeneration operation and a gear-shifting control of changing a shift stage of the automatic transmission by outputting a gear-shifting signal in accordance with the rotation speed of an input shaft to the automatic transmission. When the controller determines an oversteered state of the vehicle during the regeneration control, the controller increases an input torque of the input shaft so that the regenerative braking torque decreases while maintaining the regeneration operation of the motor and, at the same time, limits the gear-shifting control.

Systems for controlling the speed and direction of vehicles, including vehicles that have low to zero turning radius capability.