Motion-Pressure Prototype Fabrication

Title: Embedded + mechanical engineer: wireless sensor-triggered fluid dispenser prototype

Project
Build a proof-of-concept of two paired units: a remote trigger and a dispenser. The trigger is either a motion sensor or a weight-threshold pad (wired to the trigger unit). The units link wirelessly so the trigger can be mounted remotely. One trigger pairs to one dispenser. Indoor use. Water-based fluid. Full application details shared under NDA after shortlisting.

Requirements

User-adjustable on the dispenser: spray duration, activation delay, force, and pattern (fine mist or direct stream)
Weight trigger works as a simple threshold trip, same behaviour as motion
Both units: rechargeable battery, USB-C charging, and direct USB-C operation that bypasses the battery
Enclosure: 3D-print/CNC for prototype, with a clear path to injection molding
Production-grade, multi-sourced parts with an alternate for each critical component
Wetted path (pump, tubing, nozzle, seals) rated for common additives

Deliverables

1 working prototype pair plus 1 spare trigger unit, shipped to me
Schematics, Gerbers, firmware source (KiCad or Altium; Arduino/ESP32/STM32)
STEP files for enclosures and moving parts
Costed BOM
Full IP assignment to me on payment. No reuse of the design for other clients.

Acceptance

Trigger-to-spray latency under 300 ms, excluding user-set delay
20 of 20 consecutive trials pass, per trigger type
No false triggers over 60 minutes idle
Each setting measurably changes the output

Milestones

Concept, wireless protocol and pump choice, draft BOM
Design sign-off, then schematic/PCB/CAD complete
Assembled prototype and firmware
Shipped, tested, accepted

Apply with all four, or you will be ignored with fixed cost estimate