An open-hardware, industrial-scale in-bay car wash architecture that replaces the traditional moving overhead gantry with a servo-driven turntable and parallel Spray Column modules.
Goal: increase throughput, simplify hose/cable routing, and improve maintainability by “inverting” the conventional in-bay design.
This project is OSHWA Open Source Hardware Certified.
- OSHWA Certification ID: VN000001
- Certification page: https://certification.oshwa.org/vn000001.html
Most in-bay automatic car washes rely on an overhead gantry that moves back-and-forth along the vehicle. While widely adopted, this approach tends to increase mechanical complexity and adds stress to hose routing and cable management due to constant motion and repeated travel paths.
This project explores a different architecture aimed at:
- reducing moving-axis complexity,
- enabling easier maintenance and modular expansion,
- improving process parallelism (multiple wash actions at once).
Turntable Car Wash reverses the common approach:
- The vehicle rotates on a servo-driven turntable (angle-accurate rotation).
- The washing hardware is organized as stationary modules (Spray Columns) around the vehicle.
- By eliminating the moving gantry, hose/cable runs can be shorter, less twisted, and easier to service.
With the gantry eliminated, multiple Spray Column modules can work in parallel:
- Pre-soak, wash, rinse, wax, and spot-free can be distributed across modules.
- The system can reduce reliance on repeated serial gantry passes.
- Control logic focuses on orchestrating parallel actions and optimizing rotation timing.
Key subsystems include:
- Servo-driven turntable for smooth, angle-accurate rotation
- Spray Column modules (modular washing columns)
- PLC control for deterministic motion + sequencing
- Embedded PC software
- Electrical system integrating PLC, servo drive(s), pumps and sensors.
- Industrial mechanical structure designed for replication and serviceability (sheet metal/bolted assemblies)
├─ Spray column/ │ └─ SolidWorks design files for the washing module (Spray Column) ├─ Turntable/ │ └─ SolidWorks design files for the servo-driven turntable ├─ Software & PLC/ │ ├─ PLC source code (control logic, sequencing, motion) │ └─ Embedded PC software source code └─ Electrical/ └─ Electrical drawings for PLC, servo, pumps, and overall control system
An MVP prototype with a single wash module has been built and tested. Early observations indicate that:
- The architecture is feasible for in-bay operation.
- Optimization of rotation + spray timing has a measurable impact on wash quality and resource usage.
- Long-term reliability will depend heavily on the turntable subsystem design (sealing, drainage, and protection in wet/chemical environments).
The turntable is the most demanding subsystem, with challenges including:
- long-life bearings and sealing in a wet, chemical environment,
- debris / grit intrusion protection,
- drainage and corrosion mitigation,
- mechanical rigidity under vehicle load,
- safety interlocks and fault handling for rotating machinery.
Video demo: https://youtu.be/eL5WlzASyZ8
This project is released as open hardware under the CERN Open Hardware Licence (CERN-OHL-W).
- Hardware files: CAD (SolidWorks), electrical drawings
- Control: PLC code
- Software: embedded PC components
See the LICENSE file for the exact terms.
This is an industrial machine concept involving electricity, rotating machinery, pressurized water, and chemicals. You are responsible for ensuring compliance with local electrical/mechanical codes, safety guarding, E-stop strategy, interlocks, and chemical handling requirements before building or operating any derivative system.
Contributions are welcome:
- mechanical design improvements (turntable sealing/drainage, modularization)
- PLC sequencing and safety logic
- embedded software
- documentation (assembly, commissioning, maintenance)
Long Phan — inventor and R&D contractor working across mechanical design, automation, software, and IoT. For questions, please contact: longphan@ieee.org