A novel improved broyden's method has been presented to estimate image jacobian matrix for uncalibrated visual
servoing. In this paper, we apply chebyshev polynomial as a cost function to approximate best value. Compared with
recursive least square (RLS) algorithm which is restricted by the prior knowledge for obtaining some performances,
chebyshev polynomial algorithm has a great adaptability to estimate jacobian parameter, even without the prior
knowledge. A microscopic image jacobian model has been developed for the four degree-of-freedom micromanipulator
in our microassembly system. The performance has been confirmed by simulations and experiments.