Two-Link Arm IK (2R)

This interactive simulator explores Two-Link Arm IK (2R) in Engineering. Planar 2R manipulator: mouse goal, elbow-up / elbow-down inverse kinematics; joint angles live. Use the controls to change the scenario; watch the visualization and any graphs or readouts to connect the model with lectures, labs, and homework.

Who it's for: Best once you already know the basic definitions and want to build intuition. Typical context: Engineering.

Key terms

  • two
  • link
  • arm
  • two link arm ik
  • engineering

How it works

Planar two-link arm with inverse kinematics: drag on the canvas to move the goal (magenta). Toggle elbow-up vs elbow-down for the second algebraic branch.

Key equations

c₂ = (x²+y²−L₁²−L₂²)/(2L₁L₂)

θ₂ = atan2(s₂, c₂), θ₁ = atan2(y,x) − atan2(L₂ sin θ₂, L₁+L₂ cos θ₂)