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AOJ's Domination Timers

Updated: Apr 16

This time, I've been engrossed in crafting a quartet of timers tailored for domination games. The concept is elegantly simple: when a team reaches one of the timers, they press and hold the button corresponding to their team colour, triggering the countdown. There are three game types, one counts down to own the zone, another awards points which has multipliers based on the duration the button is held and the other allows for zones to be taken and retaken. As the timer ticks down, that territory is either claimed by the team, transforming into a strategic spawn point for their operations or awards points to that team, depending on the game mode in play.

Team synergy becomes paramount; a lone operator manning the button would find themselves vulnerable, relying heavily on their comrades' support to secure the zone.

The setup is encased in a PVC 200 x 120 x 75mm Junction Box, housing a 20x4 I2C LCD display adorned with three vibrant color-coded buttons, three LED indicators, a buzzer, all activated by a key switch. Powering this apparatus are two 18650 batteries, supplying 7.4 volts at 1200mAh. At the heart of the circuit lies an Arduino Nano, each timer meticulously calibrated to span three minutes. With this configuration, the device can remain operational for up to 12 hours before necessitating a recharge.

The foundational system was prototyped using an Arduino Uno, with code streamlined to a concise 83 lines, ensuring easy management and customization of the timer system in just one line of code for all three teams simultaneously.

The wiring has been engineered with modularity in mind, facilitating swift part replacements with minimal soldering, thanks to thoughtful design considerations.

Initially contemplating a nano shield for cable management, I ultimately opted for direct soldering onto a PCB (Printed Circuit Board), complemented by terminal clamps for effortless attachment to buttons and LEDs. This design allows for quick troubleshooting and replacement in case of malfunctions, minimizing downtime to mere minutes.

The most challenging aspect of the endeavor proved to be fashioning precise rectangular cuts on the rugged plastic to accommodate the LCD. Armed solely with a Dremel, achieving clean, straight cuts presented a formidable task. Gratefully, Aggots lent a hand, handling this meticulous task on my behalf, allowing me to focus my efforts on the circuitry. Crafting a single unit demands approximately eight hours of meticulous work.

The most time consuming part has been putting the board together, while it may not look like much, it is small, finnicky and takes patience to put it together.

In light of my previous projects, inquiries have surfaced regarding the possibility of commercializing these devices. While I entertain the idea of offering them for sale to fields, the cumulative expenses encompassing parts, labor, and time would inevitably reflect in a substantial sale price.

These timers will be used at our upcoming Camp Devgru game on May 18.

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Apr 02
Rated 5 out of 5 stars.

That sounds sooo cool! Slowly take over the whole field! Looking forward to see those things in the game! Did you ever fix that Foghorn for the game start and end count down? That worked brilliantly and saved us so much time checking our watches to see when the game finished.

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It had a battery issue, I am hoping to have time to fix it for the May game.

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