OPEN EXPERIMENTS / MUJOCO × JEV

From state
to motion.

One robot. Five physical tasks.
A closer look at what language-driven control can do — and where it fails.

Measured simulator state → intent → action

SIMULATION OBSERVATORYFRANKA PANDA
Franka Panda placing an orange cube beyond a red obstacle gate in the actual MuJoCo simulation
CONTACT. CONTROL. CORRECTION.Actual evaluated scene · gate pick & place
STRUCTURED STATE INPHYSICAL MOTION OUT
05physical tasks
100evaluated episodes
10seeds per task & policy

Two independent policies.
Every completed failure counted.

01 / EXPLORE THE LAB

Watch a decision
become an action.

Pick a task, then watch the original demonstration. Every movement comes from JEV decisions and physical contact.

JEV / ORIGINAL EVALUATION

Simulation-time playback; API waits are omitted. New task videos are captured from the formal evaluation and end with a labeled two-second still. Original task videos use separate demonstration seeds.

02 / MEASURED, NOT ASSUMED

The results.
Including the misses.

Ten fixed seeds for each task and policy. Shared physics and success checks. Independent rule baseline. Two frozen campaigns.

Successful trials

JEVRule
Loading results…
Full results & confidence intervals 5 tasks / 100 episodes
TaskJEVRuleJEV Wilson 95%

Ten trials are a small sample. Even 10/10 does not guarantee future success. These results describe the evaluated scenes, not general-purpose manipulation.

03 / UNDERSTANDING FAILURE

A failure is a result.

Seven failed trials in the new 40-episode campaign. Their original outcomes, measurements and boundaries are preserved.

01 / CONTACT

The cube clears.
The arm collides.

Four gate trials ended when link5 touched a post during lowering.

15.03–44.00 Nmeasured force / 0.05 N limit
02 / DIRECTION

A wrong turn,
repeated.

Two JEV trials requested +Y while the measured grasp direction was −Y. The object was never grasped.

302 / 305rejected actions / 350-decision budget
03 / VALIDATION

An inconsistent
model choice.

One JEV response selected an option below the maximum probability. That action was not executed.

0.49 < 0.50selected probability / maximum
Inspect all seven failed trials JEV + rule baseline
Task / policySeedDecisionEvidence & boundary

04 / INSIDE THE LOOP

State. Intent. Motion.

JEV receives structured simulator measurements. Physical success is checked independently of what the model says.

01 / OBSERVE

Read the state.

Object poses, tool position, finger contacts and geometric relationships.

02 / INTENT

Choose the next step.

JEV selects a task-specific intent: approach, grasp, carry, lower or release.

03 / ACTION

Choose the motion.

A second JEV decision selects X, Y, Z directions and a gripper command.

04 / EXECUTE

Let physics respond.

Cartesian control, real contact, measured feedback and independent evaluation.

Structured state, no camera input. No rule fallback for JEV. Evaluated in MuJoCo; real-robot generalization remains untested.

05 / OPEN & REPRODUCIBLE

Your turn at the controls.

Python 3.11 · MuJoCo · Franka Panda
Run the rule baseline locally, or bring a TypeSafe key for JEV.

Get the code
START AN EXPERIMENT
# Loose-fit insertion
robojev --task peg_insert --policy rule

# Language-driven obstacle transport
robojev --task obstacle_pick_place --policy jev