Project objective
The objective was to define a practical Spintron-style camshaft dyno architecture that could spin a camshaft through controlled speed profiles and capture synchronised measurement data. The project was framed around turning a rotating mechanical test rig into a usable measurement system: cam angle, RPM, displacement, run state, and logged data all needed to line up.
Design requirements
- Spin a camshaft through controlled speed profiles using a VFD-driven motor system.
- Measure shaft position and RPM using robust optical encoder feedback.
- Measure valve or follower displacement using laser displacement sensing.
- Synchronise encoder timing, displacement data, and run-state information for analysis.
- Use a microcontroller-based data acquisition architecture suitable for high-speed measurement.
- Keep measurement hardware, power electronics, isolation, grounding, and safety constraints in mind.
System overview
The concept separates the system into speed control, real-time sensing, embedded data acquisition, and PC-side visualisation. The encoder provides the timing reference, the laser displacement controller provides valve-motion information, and the STM32 controller coordinates capture, buffering, communications, and control-state information.
- Controller
- NUCLEO-H743ZI2 / STM32H7
- Speed control
- VFD via isolated RS-485 / Modbus
- Position feedback
- US Digital E6 optical encoder via RS-422 receiver
- Displacement sensing
- Keyence laser displacement controller into protected ADC front end
- Data handling
- ADC DMA, encoder capture, buffering, live logging
- Interface
- PC dashboard for run setup, control, and visualisation
My technical contribution
- Defined the high-level control and measurement architecture for the camshaft dyno concept.
- Mapped the data flow between PC dashboard, STM32 controller, encoder feedback, laser displacement input, and VFD control.
- Investigated encoder signal handling, protected analog measurement, isolated communications, and real-time data logging requirements.
- Considered practical test-rig constraints including noise, grounding, calibration, wiring, sampling, and traceable logged results.
Technical detail
The core engineering challenge is synchronisation. RPM and cam angle must be derived from encoder feedback while displacement samples are captured through a protected ADC path. VFD control introduces power-electronics noise, so isolation, grounding, cable routing, differential signalling, and validation become part of the design rather than afterthoughts.
The system also needs to be understandable to a test operator. A useful dashboard would not only start and stop a run, but show live RPM, capture displacement data, record metadata, and export data for later analysis.
Results and evaluation
The project produced a clear concept architecture for a camshaft dyno measurement and control system. It identified the main hardware blocks, communication links, sensor paths, and validation risks needed before implementation. The design meets the initial objective at concept level by showing how controlled camshaft rotation and synchronised displacement/RPM capture could be achieved, while leaving physical rig commissioning, calibration, and measured performance as future validation work.
Visual gallery
Future improvements
- Build and document the physical rig wiring, protection, shielding, and isolation layout.
- Validate encoder capture, RPM calculation, displacement calibration, and ADC sampling accuracy.
- Develop the PC dashboard for run setup, live data display, and logged result export.
- Run controlled tests to evaluate repeatability, noise, speed stability, and measurement uncertainty.
- Add real test photos, calibration plots, dashboard screenshots, and measured run data when publicly shareable.