The pose, straightness and working state of hydraulic supports are important indexes for engineering quality evaluation of fully-mechanized mining face and the key to ensure the continuous advancement of unmanned working face. The motion process restoration method describing the pose of the hydraulic support with 6 degrees of freedom(DOF), 3 position DOF(u, v, w) and 3 orientation DOF(θ, φ, ψ), was proposed. Based on this method, a model for measuring the pose and straightness of the hydraulic supports was designed by using a detection robot. The paper focused on the research of the robot pose measurement theory in the process of support pose detection. Then, the structure and size of laser launching and receiving devices were determined. By analyzing the structure model and establishing the coordinate systems, the inverse motion calculation formulas of the detection robot pose with 6 DOF parameters were derived on the basis of the 6 coordinates of the 3 points on the laser receiving device, and the motion process restoration of robot pose was realized. Finally, the correctness of the inverse motion calculation was verified by positive motion calculation and motion simulation in three-dimensional virtual environment. This work lays a foundation for subsequent experimental research on the measurement and adjustment of hydraulic supports' pose and straightness.