Robotics / Digital twin / Check against prediction

Digital twin · prediction check

Reach and hold against Held load

Observed run

Prediction

watchsim

Both runs are simulations: the observed run stands in for a real joint until a device posts one with source device:<id>.

The observed run carries nothing held; the prediction carries 0.3 kg on tool.

Observed
Printed arm, stand test ok
Prediction
Printed arm, stand test ok
Rules
command within 0.01 rad rms; position watch 0.02 rad rms, fault 0.1 rad max; current watch 25%; winding watch 5 °C, fault 15 °C

Joints

JointStatusCommand apartPosition off (rms)Position off (max)Current offWinding ΔHealth
base simcompared0.0000 rad0.0013 rad0.0090 rad129% (0.252 A)-0.1 °Cwatch
shoulder simcompared0.0000 rad0.0012 rad0.0110 rad51% (0.912 A)-5.4 °Cwatch
elbow simcompared0.0000 rad0.0015 rad0.0168 rad66% (0.536 A)-7.8 °Cwatch
wrist simcompared0.0000 rad0.0010 rad0.0108 rad94% (0.226 A)-1.5 °Cwatch

base watch

current is 129% off the prediction (0.252 A rms)

200 samples over the first 19.9 s of each run.

Position (rad)
base position, observed against predicted

observed solid, predicted dotted.

Current (A)
base current, observed against predicted

observed solid, predicted dotted.

Winding (°C)
base winding temperature, observed against predicted

observed solid, predicted dotted.

shoulder watch

current is 51% off the prediction (0.912 A rms); winding peaks 5.4 C below the prediction

200 samples over the first 19.9 s of each run.

Position (rad)
shoulder position, observed against predicted

observed solid, predicted dotted.

Current (A)
shoulder current, observed against predicted

observed solid, predicted dotted.

Winding (°C)
shoulder winding temperature, observed against predicted

observed solid, predicted dotted.

elbow watch

current is 66% off the prediction (0.536 A rms); winding peaks 7.8 C below the prediction

200 samples over the first 19.9 s of each run.

Position (rad)
elbow position, observed against predicted

observed solid, predicted dotted.

Current (A)
elbow current, observed against predicted

observed solid, predicted dotted.

Winding (°C)
elbow winding temperature, observed against predicted

observed solid, predicted dotted.

wrist watch

current is 94% off the prediction (0.226 A rms)

200 samples over the first 19.9 s of each run.

Position (rad)
wrist position, observed against predicted

observed solid, predicted dotted.

Current (A)
wrist current, observed against predicted

observed solid, predicted dotted.

Winding (°C)
wrist winding temperature, observed against predicted

observed solid, predicted dotted.