A silly title for a serious workstation!
As the development of our first motor bogie product continues, what became clear to us was the need for a dedicated R&D test workstation for motor drives and control electronics.
Thus, over the summer we have been building up this lab workstation with these features:
1. Fully instrumented track test loop - A loop of mixed LEGO and Fx Track elements enables continuous evaluation of bogie performance. The loop is fully instrumented for voltage, current, power, and vehicle speed. A laser spot thermometer can take snapshot measurements of temperatrure as well.
2. Programmable power sources - The test loop or a standalone motor can be energized with either high precision/programmable DC voltage/current or NMRA DCC digital AC waveforms. This will allow development of both DC and DCC motor drive products.
3. Computer control - both manual and automatic measurement tasks can be performed with the aid of software. All of the sources, sensors, and test equipment is connected to an M1 Mac Mini. Custom built software scripts control measurement tasks including both instrument control and data acquisition.
Some of the tasks that we can perform are:
1. Dynamic motor bogie tests - including speed, power consumption, and efficiency as a function of applied voltage. This lets us characterize raw performance, endurance and can even detect differences in vehicle speed in straight vs. curve track segments.
2. Standalone motor evaluation in a special jig. We can measure motor power consumption, efficiency, temperature, and shaft tachometer speed. The temperature is particularly important when you consider that it will "live" inside a plastic box with potentially hours of continuous running. This will inform us on thermal management requirements for the bogie design, e.g. if we need heatsinks, cooling vents, etc.
The oscilloscope lets us monitor either track or motor terminal waveforms in realtime. This shows the motor's dynamic electrical characteristics such as inductive surges, back EMF, and estimate EMC/EMI performance. It also lets us analyze DCC digital waveforms on the track and verify compliance with timing and programming protocols.
This workstation is continuously evolving and we're currently road testing 3x engineering test samples of candidate motors provided by our motor manufacturing partners. Once we're satisfied with our choice we can finalize the mechanical drive and hopefully start tooling components!
Lots more work to do—but at least we have our own "Nurburgring"!