My previous Instructable covered the basics of detecting dart speed using an infrared emitter and detector. This project takes it a step further, using a printed circuit board, display, and batteries to make a portable ammo counter and chronograph. Additionally, we add some LEDs to simulate muzzle flash. Because, pew pew pew . . . Reading more about Arduino for Nerf: Chronograph and Shot Counter
Arduino for Nerf: Chronograph and Shot Counter
This may seem like a daunting project with lots of steps, but the use of a printed circuit board and commercial components for the display and microcontroller make it much easier to assemble a reliable project. I will also provide test code for each element of the project to help ensure your success. You can do it !
Step 1: Parts and Supplies
Printed Circuit Board, three copies will cost you only $12.40 with free shipping, so make this with a friend to share the cost:
Electronic Parts
- 1 ea., Q1 MOSFET N-CH 20V 530MA TO92-3, Microchip TN0702N3-G, https://www.digikey.com/short/pjvt3t
- 5 ea., 5mm LEDs, color of your choice
- 6 ea., 100 ohm 1/8W 5% current limiting resistors, https://www.digikey.com/short/p49zp2
- 2 ea., 10K 1/8W 5% resistor, https://www.digikey.com/short/pjvt3t
- 1 ea. Photo Transistor, [Everlight PT928-6B-F](https://www.digikey.com/short/qtrp5m)
- 1 ea. IR Emitter, [Everlight IR928-6C-F](https://www.digikey.com/short/jzr3b8)
- 1 ea. 100 ohm resistor 1/8W 5%, [Stackpole CF18JT100R](https://www.digikey.com/short/q72818)
- 1 ea., male-male 12″ jumper wires, [Adafruit 1955], (https://www.digikey.com/short/pzhhrt)
- 1 ea., Adafruit ItsyBitys 8Mhz 3V, [Adafruit 3675], (https://www.digikey.com/short/pzhhwj )
- ea., BATT HOLDER AAA 3 CELL 6″ LEADS, https://www.digikey.com/short/p49zmp
- A ea., SWITCH SLIDE SPST, E-Switch EG1218, https://www.digikey.com/short/p49h4v
- B ea., SWITCH TACTILE SPST-NO 0.05A 24V, TE 1825910-6, https://www.digikey.com/short/p49hh2
- Mea., 7-segment I2C display:
- RED Adafruit 878 https://www.digikey.com/short/p49zhh
- Blue Adafruit 881, https://www.digikey.com/short/p49zh2
