Drag tree / 2 lane timing system project - ideas gathering

[Mad Ax 9325]

Short Version

I'm thinking of designing and building a 2-lane Christmas tree with built-in timing, for use with monster truck racing and drag racing.  I'm not expecting it to be marketable as a club-level project but might help people who want to have ad-hoc races and don't mind a bit of woodwork, wiring and Arduino installation.  With that in mind, I'm looking to gather ideas for features, things that would be useful or necessary, and what would make a good usable system that people can self-build for their own setups or maybe use to kick off a basic drag race or monster truck club.

 

Long Version

I've had this idea floating in the back of my head for a while.  There's no monster truck racing at all in the UK right now, and before the pandemic started I was wondering what it would take to get one going, and I figured if I had my own timing system it would make it easier to run some friendly races.  Now that we're back in lockdown with no idea when the race calendar might get going again, I'm looking for ways to improve my garden racing experience.  I've got my ramps, I've got a fleet of monster trucks coming along nicely, but I don't have a timing system.

Initially, my plan is to build a very basic system with a push-button to start the countdown, a simple three-step bleep that tells me when the timer has started, and then a laserbeam that is broken when I cross the finish line.  Time will be displayed on an LED display.  I can do all this using cheap components and some simple Arduino code.  I'll call this version 0.10b.

Now what usually happens with my custom code projects is they become just about good enough to be sort of usable at home with a little bit of persuasion and a whole lot of hassle, and then they never move on from that point, but assuming I get over the initial hurdle, I'm looking at making a more complete system.

0.20 will have a starting beam as well as a finishing beam.  This means I can DQ any run that starts before the buzzer sound, and also I can log reaction times as well as total run time.  Even for solo racing, this will be a nice feature as I'll know for sure that I'm not cheating.  For my setup, I'll plan to build the starting beam into a wooden plate (carpeted for traction) to make it easier to set out, and also so I can start from a tabletop like some monster truck races do.  I'll probably build the finish beam in the same way - then setup is basically just throwing it on the floor and plugging in the wires.  I don't plan on using this for street cars (my garden is not 1.9 friendly) so a little bit of a bump as I drive onto the finish line is OK.

Whether I get beyond 0.20 really depends on what happens with 2021.  If there's proper racing then I'll probably get out and race as much as I can and the project will languish unfinished like everything else.  If we're not allowed out at all then I'll carry on developing the project in single player mode.  If we're allowed out but only in small groups then it's possible I'll extend what I've done to include a second lane, so I can meet a small and covidly-responsible sized group of mates in the fields and have some competition fun.  But as a rough idea, here's my future feature plans as they stand now:

Pre-staged and staged beams and lights.  Would be useful for anyone who wants to use this as a basis for drag racing.  A staged beam would be useful for monster truck racing too, as we can be sure both trucks are in the correct position before the countdown starts.

Christmas tree with lights.  Personally I think a buzzer is better - especially for monster truck racing as I'll want to be watching my truck to make sure it leaves the line straight, not looking (but never staring) at the christmas tree.  However, for visual impact (if this ever gets used for a race outside my own garden) a christmas tree will look so much cooler.  Building a scale-size tree using LEDs would be easiest but for public events it would be nice to have a good sized tree with good sized bulbs, and that will need some thought and possibly a decoupled connection to the Arduino if I power it with a car battery.

Serial data output.  This is possibly the coolest idea I've had, although the one I'm least likely to use.  The Arduino can output the results of each round via serial, and a PC can be hooked up to read and store that data.  I could build a desktop race control app that takes driver data, arranges brackets, calls out heat info and stores the results as they come in.  It would have absolutely no use to me in my garden (which is why it will never happen) but if I wanted to run some friendly monster truck races, it would make it much easier to keep track of the standings.

I'd like to repeat - most of this will probably not happen, because once I have a very basic working version I'll move onto something else.  It's also likely that without a working two-lane system I won't bother to try to organise any proper monster truck race meets, and without any proper monster truck race meets I won't bother to make a working two-lane system.

However - I am open to suggestions on what a drag race christmas tree / timing system should have, what a monster truck timing system should have, any pitfalls you can see in what I'm trying to achieve, or any other advice, ideas, criticisms, accusations of plagiarism (Traxxas haven't made one of these yet, have they..?) etc. welcome here.

[Bash 356]

This sounds like an awesome project! I'm currently learning arduino as a part of my Engineering degree at Uni, and while I'm still fairly new at it, I'd love to offer to help with doing some of the testing and programming if you would like my assistance. Traxxas actually used to make a full drag racing setup with a Christmas tree to go with the funny cars they made, but they discontinued it a while back and are very expensive when they come up on ebay thanks to the popularity of No-prep drag racing over here in the US. Here is a link to the product page for it, I think it was one of the coolest r/c related accessories ever made. https://traxxas.com/products/parts/accessories/6570dragtimingsystem

[Mad Ax 9325]

Cool, that looks very similar to what I have in mind but on a smaller scale.  TBH mine will be made from bits of wood :p 

As and when I get started, I'll share my code on github so you can take a look @Bash.  I'm a C# developer and never had anything to do with C++, there's an awful lot more you have to be aware of in C++.  During my college days we started on Pascal and most of us chose to move on to C for the second year, but surprisingly we never covered object-oriented code so a lot of the principles of C++ evaded me until later in my professional career.  With that in mind - you might find my C++ code contains some schoolboy errors, which you're welcome to fix for me.

On a different note, I started making a unit test library for the Arduino.  The current version only contains the Arduino features that I was using at the point of writing, but that would be a very neat product to bring to general release if it could be used reliably.

I don't know when I'll get properly started on the code - I like to spend my Sundays in the workshop doing physical stuff, so Arduino time is limited to a couple of evenings in the week when I'm often trying to work on some fiction or music as well, but if I can flesh out a basic skeleton of the project it can progress from there.