Robotics & Control

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Forward Kinematics (2-Link)

End-effector position from joint angles of a two-link arm.

Formula

x = L_1\cos\theta_1 + L_2\cos(\theta_1+\theta_2)

Variables

xEnd x-position

L_1,L_2Link lengths

θ_1,θ_2Joint angles

Example

Compute where the hand ends up from the shoulder and elbow angles.

Did You Know?

Forward kinematics is easy; the reverse — finding angles for a desired position — can have many or no solutions.

robotics kinematics arm

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