Analytical Inverse Kinematics for a Prismatic-Revolute Hybrid Joints Radiography Robot Mounted on the Ambulance

Installing digital subtraction angiography (DSA) equipment in an ambulance can provide crucial image guidance for the emergency medical service of cardiovascular diseases. However, the commonly used C-arm is too large to be directly installed in a narrow ambulance. This article presents a compact redundant prismatic-revolute hybrid joints radiography robot that can be installed inside an ambulance to provide DSA imaging. An analytical solution, along with a self-motion algorithm based on the continuous quantum particle swarm algorithm, is proposed to achieve accurate motion control and real-time joint avoidance for the radiography robot. The experimental results indicate that the maximum error of the radiography robot is 0.42 mm, which meets the requirements for DSA image collection. During the in vivo experiment, DSA images provided by the radiography robot guided the successful placement of a stent in the internal thoracic artery of a beagle. This verifies the feasibility of the proposed analytical solution in ensuring accurate motion control of the radiography robot.