OneTool

2-Link Robot Arm Kinematics Calculator

Forward and inverse kinematics for a planar two-link arm.

Mode

End-effector x

110.7

End-effector y

181.4

What is this tool?

A planar 2R arm places the end effector at x = L1 cos θ1 + L2 cos(θ1+θ2), y = L1 sin θ1 + L2 sin(θ1+θ2). Inverse kinematics generally has two solutions (elbow-up and elbow-down) when the target is reachable. This ignores joint limits, singularities handling beyond reach checks, and dynamics.

How to use it

  1. Enter link lengths.
  2. Use FK with joint angles, or IK with a target (x,y).
  3. Compare elbow-up vs elbow-down IK solutions when both exist.