This summer, a coveted opportunity presented itself to a few video gamers who became involved in a full-time gig while stuck at home during the coronavirus pandemic.Twenty-two college interns had the chance to spend their summer assisting in the development of an online multi-player game that teaches engineering basics created by members of the Combat Capabilities Development Command Armaments Center at Picatinny Arsenal in support of their Science, Technology Engineering and Mathematics (STEM) outreach program.The scholars played, troubleshot, and submitted new ideas for the Creative All Terrain Transport System, or CATTS, a new open architecture simulation game that is designed to help reinforce the value of a STEM education and career.In CATTS, players in grades 5 and up become robotics engineers when they create virtual vehicles that they enter into virtual racing and shooting competitions. Players pit their designs against other players in a multi-player environment that plays like a third-person shooter with game mechanics that favor artillery over conventional guns -- which presents a Picatinny Arsenal twist on the gameplay.Not only do players have fun in competition, but they learn how their design choices impact their product’s durability, maneuverability and fighting ability in the virtual environment.For the intern game designers, the experience was a game-within-a-game, as their design choices also had an impact on the real-world CATTS product.“To get the game off the ground, we brought on 22 summer scholars to beta test, trouble shoot and develop the game so we could deploy it for public consumption this fall,” said Shahram Dabiri, STEM manager within CCDC Armaments Center.The scholars spent 40 hours per week June through August working on finding and fixing various problems that surfaced while playing the game."You know how they say 'a plan never survives contact with the enemy'? The same thing applies to programming,” said Brian Shepard, CATTS director and programmer. “When a game gets big enough, some cracks start to form, and the developers can't find them all by themselves.”“I believe the uniqueness of CATTS is due to the combination of these factors: fast-paced, artillery-focused vehicular combat; open-ended vehicle construction; a focus on online competition; the juxtaposition of a realistic robotics competition with goofy videogame elements; and a hefty amount of physics-based slapstick,” said Shepard.In this game, players develop and create a robot utilizing virtual polyvinyl chloride, or PVC pipes, motors, wheels, etc., to either navigate through obstacle courses or fight against other robots, said Anthony Ur, CATTS lead artist and sound technician. The game offers 20 different types of parts, such as motors, wheels and guns, to assemble the robot.Both Shepard and Ur are a part of the Gaming, Interactive Technologies, & Multimedia branch of CCDC Armaments Center.“The objective of the game is to drive your robot around the arena and shoot as many targets as you can in order to get more points than your opponent,” said Shepard. “Being able to drive around without tumbling or otherwise losing control is critical to success, so there's an incentive for players to make their robots stable without sacrificing too much speed and maneuverability. But your opponent will also be shooting at you so they can steal your points, so you have to be able to take some hits and fight back. In that sense, engineering a better robot is just as important as improving your driving and shooting skills. It's easy to share your robot blueprints with other players too, since you can copy and paste them into text files, so players are encouraged to collaborate and iterate on each other's ideas.”The game is governed by NVIDIA's PhysX (can we make this generic?), physics engine which uses rigid bodies to approximate real-world physics. In order to highlight the challenge of engineering, a robot that's both stable and maneuverable, the physics are applied naively, without the tweaks many videogames use to make gameplay easier. If a robot could be expected to tip over in real life, it will probably tip over in CATTS.The students were challenged with finding glitches within the system and offering suggestions for improvement. Some important ideas and elements suggested include informational displays in the workshop to show the total health and mass of the robot as well as information about each part; some part types, such as the corner connectors, six-way connectors and weights; and the addition of a radar.“I can't thank the students enough for all the bugs they've found,” said Shepard. “For example, your robot is supposed to explode and get rebuilt if it falls off the stage, but one player kept flying way out of bounds and missing the invisible floor that kills the robot. So I programmed the robots to self-destruct if they're too far from the stage instead. Another student pointed out to me that hitting yourself with the mini gun was a really good way to climb vertical walls due to the knockback from getting shot, so in the next iteration I made the robot not react to getting shot if it was from your own mini gun."Shepard said the students were fun to work with. Along with bug reports, they enjoyed submitting ideas or features he wouldn’t have considered himself."Somebody wanted a perfectly flat stage, and that got me thinking of roller rinks with the rotating disco lights,” he said. “I had this stained glass texture on hand, so next thing I knew, I was making a disco hall made of stained glass. When the development team is this small, it's really important to have this kind of dialogue between the developers and the community, so ideas keep evolving and getting better."At his last virtual meeting with the students Aug. 27, Dabiri thanked them for their hard work.“The game has gone from rough to amazing,” he said. “I had no idea how far we would go with this and you did amazing work; you should be proud of yourselves. Now, I know it's not the best of circumstances and I wish you were all in some lab getting dirty building stuff, but I hope you had a good time staying clean working on a game.”Once the program is completed, CATTS will be submitted to the Liberty Science Center to host on their website. Anyone who accesses the site will be able to download it and play the game themselves or arrange to have online matches.To view a CATTS video game demo, visit https://www.youtube.com/watch?v=APYifi5HG3k&feature=youtu.be.