Picasso the Drawing Robot: An Application of Inverse Kinematics

With the recent advancement in the field of robotics, Robots have become versatile in size and form and can be programmed to do the most mundane as well as the most sophisticated and specialised tasks.

Inverse kinematics is one of the key techniques in automation and working of robots and deep understanding of the same is required for designing algorithms for strenuous tasks.

The robot use algorithm which uses the concept of Inverse-Kinematics for achieving the basic task of drawing. Hence the simulated robot (Picasso) can draw basic shapes like: circle, square, pentagon and complex figures like: cat, flower etc.

Contributors : Ashwin V , Vishal Menon

Robot Manipulator Control Example File

---

About the Example

This example uses the ROBOTIS OpenManipulator Chain robot to demonstrate the design of manipulator algorithms using MATLAB and Simulink.

This submission depends on files from the following Git repository: https://github.com/ROBOTIS-GIT/open_manipulator. The startupExample script will attempt to download them, but if there are any errors there is a pre-imported model of the robot manipulator so you can still run the examples.

Forward and inverse kinematics are demonstrated using functions available within MATLAB as well as supervisory logic implemented in Stateflow.

Robot geometries are imported to MATLAB using the "importrobot" function and to Simscape Multibody using the "smimport" function. For more information on these functions check the associated documentation pages.

To learn more, refer to these videos:

• Designing Robot Manipulator Algorithms
• Controlling Robot Manipulator Joints

---

Main Example Files

1. openManipulatorIK.m

   This file shows how to import a robot from a URDF description and use the generated rigid body tree representation to implement forward and inverse kinematics algorithms

2. openManipulatorWaypointTracking.slx

   This Simulink model uses Simscape Multibody as the environment and shows how to integrate the forward and inverse kinematics algorithms into Simulink to be used with Stateflow supervisory logic to pickup a ball, follow a trajectory, and finally drop the ball.

3. openManipulatorBallTracking.slx

   This Simulink model builds on the waypoint tracking model and adds simple perception to track and catch a moving ball using a polynomial extrapolation of the ball trajectory.

4. openManipulatorTorqueCtrlCfg.slx

   This Simulink model tests the closed-loop torque controller, in configuration space, using joint position commands (no inverse kinematics or supervisory logic).

5. openManipulatorTorqueCtrlTask.slx

   This Simulink model tests the closed-loop torque controller, in task space, using end effector position commands (no supervisory logic).

---

Product Requirements

This submission was last updated and tested using MATLAB R2019b.

The required toolboxes to run all examples are:

• MATLAB
• Simulink
• Robotics System Toolbox
• Simscape
• Simscape Multibody
• Stateflow