Awesome
Robotic-Arm
The goal of the project was to study the behaviour of a 4-dof robotic arm
To simulate the robotic arm , we used Matlab with Corke's robotic toolbox.
Model the robotic arm
The first step was the modeling of the robot in the simulated environment and the definition of the necessary parameters ( links between motors, masses , inertias etc.)
Kinematics
After modeling the robot, we solved the forward kinematics by calculating the Denavit-Hartenberg paremeters
Link | θi | di | ai | αi |
---|---|---|---|---|
1 | θ1 | 0 | 0 | -90° |
2 | θ2 | 0 | 0 | 90° |
3 | θ3 | 0 | 0 | 0 |
4 | 0 | d4 | 0 | 0 |
Inverse Kinematics
By expressing the parameters of the robot as a function of the Cartesian coordinates we get the following equations:
Path Planning
To make the end-effector move in a circular path during a specific amount of time , we have to define at least 9 points to form the path and then direct the arm into them with a specified order.
Of course before we actualy move the robot, we have to solve the robot's Dynamics.
Dynamics
The formation of the Euler-Lagrange equation will enable us to find the actual forces we need to apply in the motors, to force the arm move in a certain way.
Control
Finally to optimize the movement of the robot into the specified path, it is essential to add a control mechanism. We choosed ato do that using feedforward-torque control.
After applying the control, we tried to move the robot in a circular path and measured the difference between the desired path and the actual movement.