Hi,
I made engine tester based on arduino. I would like to ask you, if someone/something does exists ? I found only too expensive commercial project: https://www.rcbenchmark.com/.

My cost only few $$ and I dont know if Im missing something. Here is what Im doing:

  • measure voltage (rezistor divider + analog input on arduino, resolution ~30mV) and current

(ACS712 20A, resolution 40mA) on ESC input, current measurement is tricky - the value is really unstable so Im doing averiging from 300 values but still... it needs improvement [$2]

  • measure thrust with weight sensor: 5KG FZ0967 + HX711 [$4.5]
  • measure vibration with MPU 6050 [$3.3]

So I can calculate:

  • power in Wats
  • efficiency in g/W

I used Arduino UNO copy with LCD + buttons shield [maybe $10 ?] + extra potentiometer. There are two modes:

  • manual - I can control input PWM with potentiometer and I can see all measured values on display and in serial monitor when arduino is connected to PC, one measure takes ~2seconds
  • automatic - PWM is going automatic from 0% to 100% with 5%step, measured values are printed to serial monitor so then it is easy copy all values to excel and make some charts..

My motivation is compare ESCs, motors, propellers to get best combination. The tool is mounted on my table during measurement so there is a lot of space around. I know it is not exatly as during real flight but still, it is good to compare.

Are you interested in or am I doing something what exist or is useless ?

btw sorry for my english..

EDIT:

video on the youtube

EDIT2:

project website: http://diy.ivosch.cz/buzz-drone-engine-tester/

Views: 953

Attachments:

Reply to This

Replies to This Discussion

more pictures

Attachments:

Thanks, but it is not so powerful.

I'm sending data through Arduino USB, so it is easy copy and paste table from Serial monitor to Excel. In the future I would like to implement RPM sensor + maybe microphone to measure noise.

I believe I've already done all what you describe, and more.

https://youtu.be/S2vaC5SftQc

Basically same as you thought of , 5kg load cell, capable of power module , or hall-effect sensor, and has serial output.

I'll open source it on github  when I am back from vacation, (saturday) - then I hope we can take it further by people

like you contributing, rather than reinventing it :)

Correction, I see that yours are quite well operating,  so you may actually have a equal or better solution.

It's very useful  as g/W is a good indicator of everything including ESC firmware and settings.

I did not find vibration measurement very useful, but have another, better idea that would I've the open source versions we have , have something no meter has today.

Nice job, it looks similar. How do you measure current ? For me it is hard to get effective value when ESC is switching 3 phases.

I want to measure vibrations to see how propellers are balanced. Because of this the motor has to be mounted on the real arm... to get real behaviour.

I am using power module, and sample +average it a lot, used ACS758 hall sensor too, needs a bit finer filtering.

As long you have a power source, (lab psu or battery), then current measuring device, then some 15cm cable length before esc (with sufficient capacitors, then the current is smoother.

this is a great diy work! 

would you share a build tutorial and arduino code?

My version will be on github next week.

To get usful comparison values you really need RPM mesurments

if you compare ESC's with same motor and same prop you can get verry different values at the same input pwm

That is true, every ESC has different throttle calibration and behavior. But to compare ESC's actually I don't need RPM. What is important to me is max thrust and efficiency. To compare efficiency is good chart efficiency vs thrust which I can create. When you use same propeller then thrust corresponds to RPM.

I will try to prepare simple tutorial "how to build" with source codes in the next week.

I created a video how works automatic mode: youtube.

Good Job Ivosch! I have done this manually with eagle tree logger and scales for years and now it's time to automate it like you did. Expecially the auto excel data export is really usefull! Will you share the source?

Here is my source as promised: https://github.com/AndKe/ThrustMeter   Please feel free to improve and share.

https://www.youtube.com/watch?v=S2vaC5SftQc

Reply to Discussion

RSS

© 2017   Created by Chris Anderson.   Powered by

Badges  |  Report an Issue  |  Terms of Service