ArmEcho

Reference Twin Physical

Reference Physical DH frames Path

Gap magnifier×12

Forward kinematics. Each slider sets one joint angle within its limits and the tool pose follows from the DH chain.

Hold tool orientation

Inverse kinematics with damped least squares. Move the target and the solver finds joint angles that reach it. With orientation held, the tool keeps its current direction.

Path

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Paths are solved once with inverse kinematics and replayed as joint trajectories. The dashed line in the view is the reference path.

Preset

Standard DH convention: Rz(θ+θ₀) · Tz(d) · Tx(a) · Rx(α). Lengths in mm, angles in degrees. Edit any cell and the arm rebuilds.

Paste a model

The physical arm is simulated. It has servo lag, command and telemetry latency, backlash and gravity droop. The twin only sees encoder readings, which sit on the motor side.

Extrapolate twin between telemetry packets

Replay a joint log

Paste rows of time (s) followed by six joint angles in degrees. The twin plays them back in place of the simulated arm.

Or load a file

Recorded data

Train a per-joint regression on a joint sweep, then test it on the circle path, which it has not seen. Inputs are the twin's gravity torque, joint velocity and direction of travel.

Apply to the live arm

Fitted terms per joint

The simulated arm is built from the same effects the regression models, so the result here is a best case. A real arm leaves more residual error.

Tracking error, last 12 s

Physical vs referenceTwin vs physical

Tracking RMSE

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Peak error

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Twin gap, mean

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Telemetry age

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