I've been working on this project for a while and I'm finally ready to share it with the control line community. Don't get your hopes up, it's not a fancy, sensor laden, super fantastic CLPA timer. (Although it's a good starting point.) The target user is a new or returning control line flyer that wants to get started with electric power. It should be sufficient for the average sport flyer as well.
The availability and cost of a good basic timer has sometimes been a challenge. A while back I converted a Flite Test Mighty Mini to use as a control line trainer and was surprised to find the timer was the single most expensive item on the BOM. When I researched the electronics hobbyist sites I was amazed at the variety of new and powerful micro-controller development boards and sensors available. So, I bought a few and started experimenting. I'm definitely not an senior embedded system engineer nor a crack programmer. I'm just a techy OG with a desire to make a better mouse trap. My code may be a bit of a brute force attempt, no fancy OOP here, the bottom line is, it works!
I call it the
Touch_and_Go timer and I hope a lot of flyers try it out. The program code is a free download and yours to modify as you see fit. The hardware costs $8.95US and is distributed all over the world and is available from numerous local online vendors. No expensive shipping and duties to worry about. There is a bit of soldering of pins involved to complete the assembly. The manufacturer of the board has made it super easy to program. If you can copy and paste a file, you can program the board. No other complicated software to download and install. Simple code changes can be done using a text editor already on your computer.
I tried to include as many features as possible. It's small and lightweight, field programmable (without any additional tools, boards, boxes or laptops) and usable with inexpensive ESC's. While there is no direct RPM feedback, it does boost the RPM to compensate for decreasing battery voltage over the course of the flight. One of the pins is set-up as a capacitive touch sensor which is used for operator input. A multi-colour LED is used as output, indicating the status of the timer.
I put a lot of effort into making it as easy as possible for anyone to make their own. Please make one of these 'do-it-yourself' timers and let me know how you make out and tell me what you think. I set it up as a GitHub project, if you are familiar with that (not a requirement).
All of the details can be found on my webpage:
https://circuitflyer.com At the bottom of the page is a link to a PDF file for the complete instructions (I've also attached it here). The program code can be dowloaded from a button at the top of the webpage.
There you go, folks. Take it from here and see where this open source project leads. I hope it promotes at least a few new electric control line flyers.
Paul