This Gator™ XUV Crossover Utility Vehicle is equipped with power steering and a dual A-arm front suspension. These automotive-type systems exhibit excellent handling characteristics, as well as responsive steering and low steering effort:
Steel ball-bearings secure the steering shaft and deliver smooth, responsive operation
Tight turning radius of 3.8 m (12.4 ft) two-passenger or 10.4 m (34.1 ft) four-passenger for excellent maneuverability
Completely sealed rack-and-pinion for long life
- Low steering ratio (lock-to-lock) provides more responsive steering and less operator input
Shaft U-joints are phased for a smooth, uninterrupted motion of the steering wheel
Electric power assist steering system
Electric power assist steering (EPAS) system has advanced features:
- Anti-kickback feature reduces the amount of steering unwinding when traversing difficult terrain.
- The system is speed sensing and adjusts steering effort as the speed of the vehicle changes.
- As speed increases there is less steering assist for improved road feel.
- As speed decreases steering assist increases to give lower steering efforts for improved maneuverability.
- A warning/functional light on the instrument panel provides self-diagnostics and a warning light in the situation of no assist.
- Torque sensor measures steering wheel input so the on-board computer can provide the appropriate output for various driving situations.
With the EPAS system, the operator maintains a direct mechanical linkage from the steering wheel to the front wheels. The power steering system interfaces mechanically with the steering system by being inserted between the steering wheel and the rack and pinion assembly.
A differential torque sensor is integrated into the power steering assembly. The circuit board assembly is also integral with the power steering assembly.
Power steering does not reduce turning radius but significantly reduces steering effort, by approximately 85 percent compared to those models without power steering.
EPAS interface diagram
EPAS interface diagram
The numbered descriptions refer to the EPAS interface diagram shown above:
- Torque sensor
- Fail-safe relay
- Current/thermal control circuit
- Reduction gears
- DC motor
- Rack and pinion
- Function/warning light
- Key power and ground
- Vehicle speed sensor
- Instrument cluster
- Relay module
The tire scrubbing, which also creates unwanted heat and wear in the tire, can be eliminated by turning the inside wheel at a greater angle than the outside one (Ackerman steering).
NOTE: Some competitors use parallel steering instead of Ackerman steering.
Bump steering defines the change in the forward steering angle (thus wheel position) as the suspension travels through its full motion. A large amount of angular change (5 degrees to 7 degrees) will alter the vehicle's direction and excessively move the steering wheel.
Ackerman steering design
Ackerman steering design provides more responsive steering, decreases tire wear when used on hard surfaces, and is turf friendly (see description below).
Minimal bump steer eliminates unintended vehicle direction changes when traversing terrain and permits less feedback to the steering wheel (see description below).
Ackerman steering graphic
The Ackerman steering principle defines the geometry that is applied to all vehicles (two- or four-wheel drive) to enable the correct turning angle of the steering wheels to be generated when negotiating a corner or a curve.
The red lines in the picture represent the path that the wheels follow. One can notice the inside wheels of the vehicle are following a smaller diameter circle than the outside wheels.
If both of the steering wheels were turned by the same amount (parallel steering), the inside wheel would scrub (effectively sliding sideways). This wears the tires on hard surfaces, scrubs or tears the turf, and lessens the effectiveness of the steering.