Jumper is a 22-DOF, six-limbed companion robot from KingKong Robotics: four walking legs for quadrupedal locomotion and two gripper-equipped arms for simple grasping and expressive gesture, all in a 400 × 400 × 200 mm, 1.8 kg body. It ships with an open-source MuJoCo/Isaac Lab training stack the maintainer uses for its own walking, jumping, dancing, and gesture behaviors, built on mjlab and rsl_rl.
The mechanism
Four legs (left/right × middle/rear) each carry 3 actuated joints — hip yaw, hip flexion, and knee flexion — for walking and jumping. Two front limbs (left/right) are 5-DOF arms instead of legs: shoulder yaw, shoulder pitch, elbow, wrist, and a single-DOF gripper finger, each ending in a two-pad palm for grasping. All 22 joints are independently actuated — no mimic joints, no shared or coupled motion.
About these files — read before importing
This links directly to KingKongRobotics/jumper, the manufacturer’s own repository. Every link’s mass and inertia is measured CAD data (the project’s own conventions document records the exact reference values and explicitly prohibits silently recomputing them), and collision geometry intentionally reuses each link’s full visual mesh rather than a simplified proxy — the project’s own documentation notes MuJoCo treats these as convex hulls regardless. ARMOR links directly to that repository rather than re-hosting anything, so what you get is exactly what KingKong Robotics publishes, unmodified.