Vehicle Ride

1. Wheel rate is usually different from the spring rate, because of installation ratio

2. Ride rate is a measure of vertical force per unit deflection at the tire ground contact reference point with reference to chassis. Tire\'s vertical stiffness accounts for the difference between ride rate and wheel rate

3. 1.) No. The same amount of damping cannot be used for low and high frequency regions

2.) No. During compression of spring, the spring absorbs energy and hence, the damping force needs to be lower to avoid over-damping. During rebound, spring releases energy and therefore, a lot of damping force is necessary to control the force released by spring

4. To achieve flat ride by reducing the time delay between front and rear wheels hitting the bump

5. For improved vibration isolation in wheel-hop region, a lower sprung mass and high damping is preferred.

6. Air suspensions have lower natural frequency owing to the softer spring rate, hence they offer smooth ride with maximum roll stability. Airsuspensions in trucks can also eliminate body lean due to uneven loads.

7. Sprung mass natural frequency- 0.0169 Hz

Unsprung mass natural frequency- 0.373 Hz

8. 1.) Time lag 1- 0.42 seconds

2.) Time lag 2- 0.141 seconds

3.) Time lag due to wheelbase- 0.15 seconds

For a flat ride, option 2 is preferred.