SeriaLimb is a browser-based 3D visualizer and motion planner for N-link revolute serial mechanisms. I built it with the help of Claude Code as a way to rapidly visualize robots with desired payload and get rough data on joint telemetry to help with motor sizing. In the program, you define a chain (up to twelve joints, each with its own length, mass, and rotation axis). Then, it can be driven three ways: nudging individual joints with sliders, dragging the end-effector directly in the viewport to invoke a CCD inverse-kinematics solver, or feeding the motion planner a set of target angles and letting it interpolate a smooth or linear trajectory. Poses can be captured as keyframes and chained into full sequences, all played back through the same planner so the motion stays physically consistent.
Under the hood, every planner run streams per-frame telemetry (joint angle, angular velocity, quasi-static gravity torque, and mechanical power) into Chart.js plots you can export as CSV or PNG. Torques come from a forward-kinematics pass that places each link's and payload's center of mass in world space, then projects the gravitational moment onto each joint's rotation axis.
Built with Vite, Three.js, Tailwind v4, and Chart.js; the full source layout and math write-up live in the README.
Code is free and open source on Github here!
