For some optical tracking measurement systems, because their size, weight and space structure are very strict restrictions, DC servo motors have to drive the loads through the several stages of gear transmission. For such a nonlinear controlled object, it is difficult to obtain acceptable control performance applying the traditional controller design method. In the paper, firstly, establish such a non-linear system dynamic model, and consider intelligent control algorithm to inhibit mechanical resonance effect for the control system performance. In order to achieve real-time control easily, the paper suggests a fuzzy numeric model with the self-regulating factor based on analytic expression for such a non-linear system. The result demonstrates that the fuzzy controller is very effective in applications. This work provides a new thought for a controller design to inhibit the low mechanical resonance frequency.