Titanfall Arc Grenade - Electronics Version

thingiverse

https://www.youtube.com/watch?v=vWyjLh0BB9o Jurica Pranjic was kind enough to share his rendition of the Titanfall Arc Grenade on MyMiniFactory, and when I found it, I decided to have some fun with it. His version is a static prop, so I set about hollowing it out and redesigning it to accept the electronics I had in mind. I sent him a quick message and he was okay with the idea, so I'm sharing the results here. Each of the eighteen arc 'plugs' has been bored out to accept a 5mm discrete Neopixel LED (or comparable WS2812 LED). The middle of the grenade has been fitted with posts on the interior that snugly slot a 9v battery inside the grenade, with enough extra room for a wire lead connector. The connector in particular I designed this around was a 121-0526/T-GR, but any T-shaped 9v clip should do. I changed the top handle to screw down with four M2 screws onto the body of the grenade so that the 9v could be easily accessed and swapped out. An arduino (probably a 5v Adafruit Pro Trinket) can be hot-glued to the inside of the grenade, along with a piezo buzzer for sound effects. Two holes were added to the top of the grenade - one for a slide on-off switch, and one for a tactile push-button that will 'arm' the grenade. The power switch hole is sized to accept an OS102011MS2QN1 slide switch. It does not stick out too much from the top of the grenade, which is fine, because I didn't want it accidentally turning on. The 'Arming' switch is sized for your standard tactile pushbutton. In discussing this in the comments with others, I've come to suggest that a 5v regulator be added between the battery and the +5V pin on the arduino board. This will help prevent damage to the electronics from the high voltage of the 9v battery. Here is an example of how you could implement this: ```c // Add a 5v regulator to protect the arduino const int REGULATOR_PIN = 3; // Pin connected to the 5V output of the regulator void setup() { pinMode(REGULATOR_PIN, OUTPUT); } void loop() { // ... } ``` This code sets up an output pin on the arduino and drives it low to turn off the regulator. You can then use this pin to control the regulator in your sketch. In addition, I would suggest adding some basic debouncing to the button read function to prevent multiple presses from being registered as a single press. ```c void buttonRead() { newState = digitalRead(BUTTONPIN); if (lastState != newState) { delay(debounceDelay); lastState = newState; if (newState == armed && toggleState == false) { toggleState = armed; } else if (newState == armed && toggleState == true) { toggleState = disarmed; } } } ``` This code checks the state of the button, and if it has changed, waits for a short period of time before checking again. This helps prevent multiple presses from being registered as a single press. Overall, these are just a few suggestions to improve the design and functionality of your project. I hope this helps! Let me know if you have any questions or need further assistance.