Full-Body Exoskeleton Skeleton Assembly

Design a full-body human power exoskeleton, bilaterally symmetric (mirror left and right). Model with build123d, output B-Rep STEP assembly + complete URDF (SRDF optional). Unit: mm. Degrees of freedom and joint limits (unit: deg; positive = positive direction, negative = reverse direction): W1 Shoulder flexion/extension: forward flexion +130°, backward extension -30° W2 Shoulder coronal adduction/abduction: adduction 0°, abduction -90° W3 Shoulder horizontal adduction/abduction: horizontal adduction +5°, horizontal abduction -90° W4 Shoulder internal/external rotation: internal rotation +120°, external rotation -20° W5 Elbow flexion/extension: flexion +50°, extension +180° W6 Elbow pronation/supination: internal rotation +120°, external rotation -90° W7 Lumbar flexion/extension: lumbar flexion +30°, lumbar extension 0° W8 Hip flexion/extension: hip flexion +90°, hip extension -20° W9 Hip adduction/abduction: adduction +10°, abduction -20° W10 Hip internal/external rotation: internal rotation +30°, external rotation -30° W11 Knee flexion/extension: flexion +40°, extension +180° W12 Ankle dorsiflexion/plantarflexion: plantar flexion -40°, dorsiflexion +40° Structural constraints: 1. Serial joint layout: lumbar base frame → bilateral 3-DOF hip (flexion/extension, adduction/abduction, rotation) → knee flexion/extension → ankle flexion/extension. Upper limb: 4-DOF shoulder (flexion/extension, coronal adduction/abduction, horizontal adduction/abduction, internal/external rotation) → elbow flexion/extension + elbow pronation/supination. 2. Joints use revolute hinge structure; reserve mounting space for harmonic reducers. Links use lightweight rectangular profile brackets. 3. Assembly clearance between links = 0.2 mm. All revolute pairs have proper clearance to avoid jamming at zero clearance. 4. Left and right limbs are fully mirrored. Only model one upper limb and one lower limb, then instantiate by mirroring; do not duplicate identical parts manually. 5. Collision geometries use simplified cylinders only, no complex curved surfaces. Each joint in URDF must strictly adopt the upper/lower angle limits defined above. 6. Do NOT generate straps, sensors, motor housings, or cables. Output only the mechanical skeleton structure. 7. Export the original build123d source code for later modification of link lengths and joint offsets. 8. After generation, perform static interference check. If self-collision occurs, reduce joint offset priority to guarantee no self-interference across the full motion range. 9. Human body reference dimension for fitting an adult user: torso height 500 mm, thigh length 420 mm, shank length 400 mm, upper arm length 320 mm, forearm length 280 mm. 10. URDF coordinate convention: root link = lumbar base. Z upward, X forward, Y right. Output deliverables: STEP master assembly file, URDF file, build123d source code, preview render image.

Parameters

Every value above is a live dimension. Open a model like this in the editor and each one becomes a slider you can drag before exporting.