Abstract: To realize the automatic capture and positioning of segments, a depth-image vision sensor is explored based on a 1P5R single-arm erector. The performance of a binocular three-dimensional (3D) sensor and a planar-structured light 3D sensor is compared and analyzed. The depth images captured by the vision sensor are matched with a segment model to determine the segment position and attitude. The hand-eye calibration of the vision sensor and segment erector is conducted to obtain the conversion matrix between their respective coordinate systems. The forward and inverse kinematics of the single-arm erector are derived using the robotic kinematics method. Six-axis travel required for grasping segments is realized by inverting the position and attitude of the segment, and a trajectory-planning algorithm is developed from the current six-axis travel to the target travel. Research and laboratory experiments reveal the following: (1) Position and attitude can be effectively obtained using the depth-image sensor and calibration. (2) The forward and inverse kinematic solutions can effectively guide the erector to realize automatic segment grasping using the position and attitude information.

Key words: depth-image vision sensor, segment erector, forward and inverse kinematic solutions, trajectory-planning algorithm, transformation matrix