Bounce Test

The vehicle chassis is exercised in a pure bounce motion. This is accomplished by moving the K&C rig’s center table straight up and down within defined displacement bounds (For example, + 2.0 inches from baseline ride height). The vehicle chassis is clamped directly to the center table, thus it is exercised straight up and down as well.

During this test lateral and longitudinal forces, and aligning moments are maintained at zero at each tire contact patch, thus canceling any unwanted tire “scrubes” forces, and allowing the suspension to move freely without binding. The slow speed of this test (cycle times are typically ~ 1 minute) removes unwanted damper and inertial forces from the tire vertical load measurements. Corresponding loads, displacements, and orientations are measured at each of the four wheels.

Here are some characteristics that are measured in a Bounce Test:

  • Bump Steer
  • Bump Camber
  • Bump Caster
  • Wheel Recession
  • Tire Radial Rates
  • Wheelbase Change
  • Track Width Change
  • W/C Lateral & Longitudinal
  • Displacement
  • Kinematic Anti-Dive & Anti-Squat Angles
  • Virtual Swing Arm (VSA) Length &  Angle
  • Ride Rates (ground to chassis, includes tire)
  • Kinematic Roll Center (KRC) Height & Locus
  • Wheel Rates (wheel to chassis only, without tire)
  • Friction / Hysteresis
  • Lateral & Longitudinal Tire Center of Geometry (COG) Displacement
  • Lateral & Longitudinal Tire Center of Pressure (COP) Displacement