Heavy Tracked Chassis Lab: Torsion-Bar Suspension, Track Tension and Steering

Torsion-Bar Suspension

The torsion-bar suspension system in a heavy tracked vehicle is designed to absorb shocks from the terrain. Each wheel station features a torsion bar that twists under load, effectively dampening vibrations and providing a smoother ride for the crew and equipment inside. This mechanism works by converting vertical forces into rotational energy, which is then dissipated or stored.

The torsion bars are typically made of high-strength steel and are connected to the vehicle’s frame through bushings. When the vehicle encounters an obstacle, such as a bump in the terrain, the wheel deflects, causing the torsion bar to twist. The amount of deflection is proportional to the force applied, allowing for precise control over the suspension's response.

Track Tension and Sag

Maintaining proper track tension is crucial for the performance and longevity of a tracked vehicle. Track sag, or the vertical deflection of the track when loaded, must be kept within specified limits to ensure optimal traction and prevent excessive wear on both the tracks and the wheels. The tension in the tracks is adjusted by tightening or loosening the idler wheel and sprocket assemblies.

Excessive sag can lead to increased ground contact area, which may improve traction but also increases rolling resistance and fuel consumption. Conversely, insufficient sag can cause the tracks to lift off the ground, leading to reduced traction and potential damage to the vehicle's components.

Regenerative Double-Differential Skid Steering

The regenerative double-differential skid steering system in tracked vehicles allows for precise control over each track independently. This system uses a combination of hydraulic pumps and motors to drive the tracks, enabling the vehicle to turn without slipping or dragging one side. The differential mechanism ensures that the outer track travels at a higher speed than the inner track during turns, facilitating smooth and efficient maneuvering.

The double-differential aspect refers to the fact that each track is driven by two separate motors, which can be controlled independently. This setup allows for fine-tuning of the steering angle and speed, making it possible to achieve tight turns and precise positioning in challenging environments.

Diesel Drivetrain

The diesel drivetrain is a critical component that converts the mechanical energy from the engine into torque for the tracks. Diesel engines are chosen for their high power-to-weight ratio, reliability, and fuel efficiency in heavy tracked vehicles. The drivetrain typically includes a transmission to adjust the speed and torque output as needed.

Modern diesel engines often incorporate advanced technologies such as turbocharging and common rail fuel injection systems to enhance performance and reduce emissions. These systems work together with the transmission to provide the necessary power for traversing various terrains, from flat surfaces to steep inclines and rough terrain.

Frequently asked questions

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