In my attempt to build my own track I have started to come up with a solution for the track timer and start gate. Below is a quick video of my prototype. I haven't built the final version, but I'm working on that and can share my experience as well.
This will require an Arduino which is fairly inexpensive to get started with. You will also need to purchase IR sensors as well.
If you have no clue how to program or work with these components no worries, baby steps and you will get there. YouTube is your friend. Look up Arduino Tutorial and you will find plenty of stuff. If you go to Paul McWorter's channel you will find a 68 video tutorial series where he goes over the Arduino and it is absolutely wonderful for beginners.
In the video below you will see 6 major components that I'm using.
The Arduino Controller (Top)
Servo motor (will be used for the start gate, on the right)
Button (You will see me press it a few times)
LED's for a starting light segment
Display (used to show the current time)
The IR sensors (right below and to the right of the button)
In the video I'm using my hand to demonstrate the IR sensors sensing my hand, stopping the clock and resetting the servo motor.
Also I'm just learning the Arduino, I got wires all over the place lol; I'm no expert on this stuff.
Hope this helps anyone who wants to do something similar. I will share the code and try to figure out how to write a schematic to show how it all works, but if you are interested in this I definitely think it is worth the time and effort to learn how to write the code and use an Arduino. a lot of cool stuff you can do with it.