A method for correcting or. Determining the impact error of the vehicle wheels for testing instruments and apparatus in this case for

摘要

In a wheel alignment system, the error caused by run-out of the axis of a fixture that is clamped to the wheel and mounts gravity stabilized inclination sensors is corrected by continuously providing fixture axis inclination signals during rotation of the wheel through at least 360. degree. from any random starting position. Maximum and minimum comparator devices continuously receive these signals. A first adder adds the maximum and minimum signals and divides them by 2 to provide a preliminary alignment signal proportional to the actual angular inclination of the wheel axis in a selected alignment plane, and the preliminary alignment signal is subtracted from an intermediate inclination signal from the sensor that represents the inclination of the fixture axis at the wheel stopped position to provide a run-out error signal proportional to that portion of the total angular run-out of the fixture axis that is present in a selected alignment plane at the wheel stopped position. When the wheel is set down, a final inclination signal is received from the sensor means and the run-out error signal is subtracted therefrom to provide an inclination signal that represents the true wheel axis inclination in a selected alignment plane corrected for run-out error, and this signal is displayed for wheel alignment purposes. The sensors measure run-out errors in both the camber and toe planes and provide separate displays for the alignment in both planes.