Torsion bars are also often used in the construction of independent wheel suspension of passenger cars and off-road vehicles. The principle of operation of torsion bars as a spring element is based on the elasticity of the torsion steel bar. Suspension solution with torsion bars. One end of the rod is fixed in a holder rigidly connected to the frame, and at the other end, supported in the bearing, the rocker arm is attached. While driving, the wheel that hits the road unevenness will deviate vertically and causes the rocker to rotate around its axis, and at the same time twisting the stick, which, due to its resilience, acts as a spring. The torsion bars may have a circular cross section, annular (tubular), rectangular or they may consist of several spring rods. Reliable operation of the stick requires, so that its working part has the smoothest possible surface, without any scratches. The advantage of torsion bars is: simplicity of construction, lightness, no need for lubrication and easy and quick disassembly and assembly. The main disadvantages of torsion bars are the need to use very good materials, complicated production process, and hence the high cost of execution.