A novel trajectory tracking strategy is developed for the swing DOF with double actuated cylinder in a hydraulic construct robot. When the work object is grabbed and unload, the inertia parameter of swing varies greatly and the estimation algorithm is commonly insufficient. Aiming at this feature, a novel nonlinear hydraulic dynamics model is established for the double actuated hydraulic cylinder in the system and a robust adaptive control strategy with parameter adaptive estimation is designed to improve the trajectory tracking performance. Aiming at the problem of insufficient convergence speed of the identification algorithm, a method of robotic gravity identification combined with stereo vision information is proposed to obtain the mass and moment of inertia parameters of the working object so that the initial value is close to the real value. Simulations and experiments are presented to validate the effect of the novel strategy.