Ackermann Linkage
Ackermann Principle as Applied to Steering Ackermann Linkage The self propelled motor vehicle almost from the beginning, used the double pivot wheel steering system. This was invented for horse drawn vehicles in 1817 by George Lankensperger, a Munich carriage builder. In England, Rudolph Ackermann acted as Lankensperger's agent and a patent of the double-pivot steering arrangement was taken in his name. With this layout of the linkage the track rod arms are set parallel to each other and a track rod joins them together. In the straight ahead position of the steering, the linkage and axle beam forms a rectangle, but, as the stub-axles are rotated about their king pins, the steering arrangement forms a parallelogram. This linkage configuration turns both wheels the same amount. Figure 27.26A illustrates the parallel-set linkage positioned to provide both a 20 degrees and a 40 degrees turn for the inner and outer wheels. Charles Jeantand in 1878 introduced an improvement to the Acker