How to cheat at Inverse Kinematics

About this video

• Video Title: How to cheat at Inverse Kinematics
• Channel: RoTechnic
• Speakers: None listed
• Duration: 00:07:19

Overview

This video demonstrates how to implement inverse kinematics for a robot arm, specifically a 6-DOF (Degrees of Freedom) arm, without delving into complex mathematical derivations. It explains the process of defining the robot's structure using URDF (Unified Robot Description Format), utilizing the ikpy Python library to calculate joint angles for a desired end-effector position, and visualizing the results. The video also shows how to control the robot arm using a game controller.

Key takeaways

• Problem with complex robot arms: Calculating inverse kinematics for robot arms with many degrees of freedom (like 6 or more) is mathematically complex and time-consuming.
• "Cheating" with existing tools: The video proposes using pre-existing libraries and tools to avoid complex math, with ikpy being the primary library used for inverse kinematics calculations.
• URDF for robot description: The Unified Robot Description Format (URDF) is used to describe the physical structure, links, and joints of the robot arm, which is then used by the ikpy library.
• Steps for implementation: The process involves defining the robot's links and joints in URDF, importing this definition into ikpy to create a "chain," setting a target position for the end-effector, and then using the inverse_kinematics method to calculate the required joint angles.
• Visualization and control: The video shows how to visualize the robot's configuration using matplotlib and pyplot, and how to send commands to a physical robot arm via a serial port.
• Game controller integration: A practical demonstration shows how to map a USB game controller's input to control the robot arm's movement in real-time.