A rocker (in blue) carrying two wheels is pivoted on each side of the car. The rockers are connected together via a violet arm and two brown connecting rods.
This arrangement ensures:
- The four wheels always contact the uneven ground.
- The car chassis (in yellow) has a definite position, although it is suspended on two coaxial revolution joints.
- When rocker 1 is immobile, the oscillating angle of the chassis is a half of the rocker 2 oscillating angle (first scenes of the video).
The connecting rods use sphere joints having unsplit outer part shown in
   • Sphere joint having unsplit outer part 2  
See a prototype of this car:
   • Robotic Lunar Rover Suspension