At the time of Carl Benz and his tricycle there was nothing to align. Later on four wheel vehicles with rigid front axles were developed; for them a mechanical measurement of the length was sufficient to adjust the track.
Afterwards, for a long time, the optical measurement with the help of mirrors and or light with preset lenses and marking systems were the optimum. Nowadays customers expect a fast measurement with automatic
desired value alignment. Possible is this only with a mobile wheel alignment gauge (picture 1) or an alignment gauge with integrated computer (picture 2).
How it works
Large volume sensors (see picture 1 to the right and left of the tester) are attached to each wheel and connected to the test computer. The information flows amongst the devices by wire or bundled rays of light. Using
new equipment it is not necessary to have the steering wheel in the neutral position. All the data can be gathered and compared to the desired value. The computer output does not focus on numbers; instead it
provides graphically a ‘pass’ or ‘no pass’.
Without the in fact necessary compensation the axle alignment can be accomplished relatively fast with modern equipment (see
picture). Modern running gears leave ever fewer adjustment possibilities – this in contrast to tuning. If the measured values deviate too strongly, parts of the wheel suspension must be exchanged.