Motion trajectory study in the scooping operation of an LHD-loader

Mining operations have great potential for automation, from a worker safety viewpoint as well as productivity and efficiency. Among the operations that can be automated are loading, guiding, and unloading of LHD loaders. This paper concerns automatic loading of these units, based on modeling a loader as a robot manipulator. For this purpose, analysis of the forces concerned in the process of scooping, and information about the kinematics of motion become essential. This work is about the trajectory of motion during scooping. Based an the results of a preliminary study on the nature of the forces involved, and bearing in mind the preference for simplicity in the control action, an easy to follow trajectory is determined for the cutting edge of the bucket of a loader, which is regarded as the end-effector in a robot manipulator. The way to find a minimum energy consuming trajectory for each individual bucket and for a particular material to be loaded is discussed. Since following this trajectory is more efficient it can be used for faster execution of bucket loading, if desired