Kinematics, workspace and trajectory of a 4-axis serial robot

What the study does

The manipulator is a four-degree-of-freedom SCARA in an RRPR arrangement — three revolute joints and one prismatic joint. Its frames are assigned with the Denavit–Hartenberg convention, and the forward and inverse kinematic equations are derived algebraically and geometrically so that joint values and end-effector pose map onto each other in both directions.

The equations are then put to work. A MATLAB GUIDE interface plots joint behaviour and the end-effector path in a 3D workspace; a full factorial experiment over the first three joints measures how each one moves the tool centre point; a point-to-point trajectory is interpolated between two poses; and a large random sample of joint configurations traces out the reachable envelope. RoboAnalyzer serves as the independent check on both the trajectory and the workspace boundary.

The closing section sets out the next step: a back-propagation neural network, with hyper-parameters tuned by design of experiments, as a real-time alternative to the analytical inverse when the closed-form solution becomes too costly.