In short. A client building a rehabilitation chair, a type of mobility system, kept the mechanical design in house and gave us the entire electronics and firmware track. We built the control box, the control panel and a remote, developed the firmware under software safety Class B and produced the documentation for a 510(k) submission. In 16 weeks and 2,100 engineering hours, for $260,000, the client received five pre-production units and a complete design history file.
How the hours were spent
Discovery about 280 hours
Requirements, interfaces with the client’s mechanics, architecture, plan.
First prototype about 720 hours
Control box, control panel and remote, with firmware.
Testing and iteration about 500 hours
Bench tests and changes from the results.
Compliance, project management and CTO engagement
Standards work, documentation for the 510(k) package and the design history file.
Why the split worked
- The client kept what it knew best, the mechanics; we brought the electronics, firmware and medical documentation.
- Each phase had its own hours: about 280 for discovery, 720 for the first prototype and 500 for testing and iteration.
- A phase plan with hours for each phase made the budget predictable: $260,000 for the whole track.
However, once you have a decent plan in the beginning, you can commit to the timeline. You can commit to the budget. So, the budget is firm. The timeline is firm.
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Sources
Client names are not disclosed. Updated on October 9, 2026.