Automation of High-accuracy Marking Tasks at MAX IV using the Quadrupedal Robot Spot

Sammanfattning: When installing new research equipment at the synchrotron research laboratory MAX IV, a final positional accuracy of tens of microns is usually needed. To obtain that accuracy, initial reference points must be placed within 2 mm from the nominal target points in CAD, in a process referred to as bluelining. It is currently a manual process where points from a virtual environment are transferred to the real working environment and marked with the help of a laser tracker. The purpose of this Master’s Thesis is to explore the possibilities of automating the bluelining process using a 12 DOF quadrupedal robot equipped with a 6 DOF and gripper robotic arm together with a Leica AT403 external tracking system. The specific robot is the robot dog Spot from Boston Dynamics equipped with a Spot Arm. The system that has been developed consists of a platform carried by Spot’s gripper containing the tracked reflector and a marking assembly, and of a software solution controlling the robot. The proposed workflow starts with a localization step where Spot finds the tracker and orients itself in the tracker’s frame. Once oriented, Spot positions itself within reach of a target point before positioning the marking device on the point using closed-loop feedback control. Once the point is reached, the operator actuates the marking device remotely after which Spot continues to the next point. With this system, a marking accuracy within 2 mm from the target was achieved repeatedly in the real working environment at MAX IV. The process time was found to be around 1 minute and 30 seconds per point, which is comparable to a human operator. From the results and data gathered during the project, it can be concluded that the proposed solution shows promise regarding both accuracy and autonomy. Furthermore, it can be concluded that similar solutions have the potential to be expanded into other areas and automate similar processes, such as marking processes for equipment installation at other types of research laboratories, as well as for booth setups at exhibitions and fares, and at construction sites when marking out mounting locations.