|
Two-link arm is a 2-degree of freedom system, where the end-effector can trace any trajectory or reach any point in the two-dimensional workspace of the system. The workspace is attached to the global reference frame.
Polar Co-ordinate plotter is also a 2-degree of freedom system, where the end-effector can trace any trajectory or reach any point in the two-dimensional workspace of the system. The workspace of the polar plotter is however attached to the local reference frame of one of the two links of the plotter.
I solved the inverse kinematic problem using geometrical methods and verified the result using the forward kinematic model of the system by D-H notations for both the systems. The inverse kinematics problem of the polar plotter interested me a lot.
Both the systems achieve the desired motion between two positions by appropriate movement of angle of each of the actuators, which in turn rotate the links coupled to them. The actuators receive the driving control signals from the computer via parallel ports. The signals from the parallel port are fed into a driver circuit, which in turn drives the stepper motors. The inverse kinematic computation of the angles that the stepper motors has to move and the parallel port signals according to these values of angles, is made in C++.
|
