Robot Neck Redesign - Reduce Motor Loading | Fusion 360 Anyone

We're Addition Robotics, building Plus, a bimanual mobile robot that works alongside care teams in senior living communities. We're looking for an experienced mechanical designer/engineer to redesign the robot's neck to reduce mechanical loading and strain on its motors.

This project covers the neck shell AND the load-bearing structure, joints, actuation, and head mounting. You'll work in our Fusion 360 team hub with the robot assembly available. We can print prototypes in-house on Bambu Lab printers and provide assembly feedback, photos, and video.

BUDGET AND TIMING
Total design budget: USD $600, fixed-price milestones agreed before work begins. Start ASAP; target completion within two months of kickoff. Please propose a milestone breakdown and confirm what you can deliver within this budget. Identify scope limitations and any separately required hardware or fabrication costs; purchases require our approval.

WHAT YOU'LL DO
1. Assess the existing design and motor-loading problem. Review head mass and center of gravity, joint geometry, load paths, actuator specifications, required motion, and available operating observations/data. Identify missing inputs before committing to a solution.
2. Propose redesign concepts with a clear explanation of how each reduces motor loading. Evaluate structural support, bearings, geometry, mass distribution, and actuation as appropriate; do not assume that larger motors alone solve the problem.
3. Compare concepts for expected loading, range of motion, stiffness, mass, packaging, manufacturability, serviceability, and cost. Support the recommended approach with concise engineering calculations and stated assumptions.
4. Develop the selected direction into detailed native Fusion 360 CAD covering the load-bearing structure, joints, actuation arrangement, head mounting, and exterior shell.
5. Preserve agreed robot interfaces and required motion. Address cable routing, moving-part clearances, pinch points, fastener access, and assembly/service access.
6. Collaborate on physical prototyping and revisions. Propose the prototype rounds included in your quote; we will agree on the iteration scope and a practical validation plan before detailed design starts.
7. Compare the revised design against the baseline using agreed calculations and physical checks. Define measurable motor-loading objectives with us after reviewing the existing design; do not assume a percentage improvement without evidence.

DELIVERABLES
- Brief assessment of the existing loading problem and recommended concept.
- Concise load/torque calculations with assumptions and relevant actuator limits.
- Clean, parametric native Fusion 360 files in our hub, with named components and a tidy timeline.
- Critical interface dimensions, component/fastener list, and assembly notes.
- Manufacturing notes, including print orientation, material, and supports for printed parts, and specifications for any non-printed parts.
- Brief prototype validation results, remaining issues, and handoff notes.

DESIGN ENVIRONMENT
Plus operates around elderly residents and is wiped down with facility disinfectants. The neck and shell must have no sharp edges or pinch points, with minimal crevices and open seams and a clean, approachable appearance. Material choices and cleaning requirements will be reviewed with us.

YOU
- Experience designing robot joints or load-bearing electromechanical mechanisms that were physically built.
- Strong understanding of motor torque, load paths, bearings, stiffness, fits, and tolerances.
- Fluent in Fusion 360; we require native editable designs, not STEP conversions.
- Practical prototyping and manufacturing experience, including FDM where appropriate.
- Clear English communication and reliable asynchronous updates.

TO APPLY
Start your proposal with "neck" and include:
1. Photos/video of a robot joint, head/neck mechanism, or comparable load-bearing mechanism you designed and built. Explain your contribution.
2. How you would diagnose excessive motor loading and which CAD/specifications/measurements you would request first.
3. An example of reducing actuator loading through mechanical design, including how you checked the result.
4. Your proposed milestone breakdown within the $600 total design budget, included prototype revisions, estimated turnaround, and any assumptions or exclusions.
5. Your hourly rate for reference, weekly availability, and earliest start date. read less