Abstract: A study on the general formula of how original errors transfer in the movement of mechanisms is carried out through analyzing the applied force placement of contiguous bar and movement trace of reference point about output, and the errors transferring matrix applied for variety of mechanics is proposed, which all based on the principle of the projection of original error in the direction of applied force. A general method is presented combining with precision analysis examples for plane and space mechanisms. The method has many general advantages such as the clear conception, without differential calculation and so on.

Key words: Mechanism, Precision analysis, Transfering matrix