Track and Field Block Start Simulator and Reaction Timer

This simple build uses a time of flight sensor and an Arduino Nano RP2040 running Circuit Python to create a motion detecting Track and Field Reaction Timer! Just plug in any speaker using the aux connection, and begin running!

• Arduino Nano RP2040
• Assumed to be set up to run Circuit Python with the necessary libraries installed
• VL53L1X TOF Sensor
• StemmaQT connector
• External Button
• Aux Female Connector
• Aux Speaker
• 1/8" Acrylic
• Laser Cutter
• Pin Connectors
• Electrical Tape
• Super Glue
• Breadboard or Sauntering Equipment (This build used a breadboard)

Code and Sound Files

Using the breadboard or sauntering, connect all of the necessary components as seen above.

Audio: D3

TOF: STEMMAQT Connections

Button: D2

Any port can be modified in the code

Using the attached Abobe Illustrator file, laser cut the acrylic to carve the box materials.

Prior to Box construction, super glue the following components in place

• Super glue the button out of the top hole of the box
• Super glue the female aux port out of the small, circular port at the front of the box

Using super glue, construct the box, but leave the top open in order to place the components inside

• Place the Arduino into the box so that the Micro USB connector is accessible out of the back of the box
• Using Electrical Tape, tape the TOF sensor so that it peers out of the top hole on the front of the box

Once everything is in place and working, hot glue the top onto the box to close it.

To use, plug in a speaker into the aux and plug power into the back. On the first button press, "On Your Mark" will be announced, instructing the athlete to get into position in front of the sensor. Then, "Set" will play, and then randomly between 2 and 4 seconds later, a gun noise will go off, instructing the athlete to go! The machine will register the reaction time, and upon clicking the button again, it will be announced. The machine will then reset and be ready to go again!