Robotics Calculators
Free robotics calculators for forward and inverse kinematics and wheel odometry.
Find joint angles, end-effector positions, and how far a robot has traveled.
Kinematics and odometry. 3 calculators, deliberately narrow rather than padded out. Motors, gearing and structural numbers sit under Engineering.
Inverse kinematics answers the harder of the two directions: given a target position for the gripper, what joint angles put it there? A two-link planar arm has a closed-form answer, and it carries a plus-or-minus that is not a rounding artefact. Two triangles can be built on the same shoulder-to-target chord, elbow up and elbow down, and both place the gripper in exactly the same spot. Industrial six-axis arms typically have 8 to 16 valid configurations for a single gripper pose, and choosing between them is most of what motion planning actually does.
Wheel odometry gets a full 2D pose out of two encoder counts and nothing else. No satellite fix, no camera, no map, which is why it sits at the bottom of every robotics stack and works in a basement in the dark. It also drifts, and the drift compounds, so treat it as a fast estimate that something slower has to keep correcting.
Inverse Kinematics Calculator (2-Link Planar Arm)
Compute joint angles θ₁ and θ₂ to reach a target (x,y) with a 2-link planar arm. Returns both elbow-up and elbow-down solutions or reports unreachable.
Forward Kinematics Calculator (2-Link Planar Arm)
Compute end-effector position from joint angles for a 2-link planar robot arm. Pair with inverse kinematics for full motion-planning workflows.
Wheel Odometry Calculator (Differential Drive)
Estimate robot position from left and right wheel encoder ticks. Calculates distance, heading change, and new pose for a differential drive robot.