Robot Bowling - 10-pin Edition

This game involves robots and bowling. What could go wrong? At ¼ scale (thereabouts), the damage is contained so this game is safe for all ages. Frankly, this is not a regulation 10-pin shape, rather, it's a more squat and bottom-heavy design optimized for robot bowling which means they are harder to knock over that they otherwise would be.

This is an update of my Canadian Robot Bowling game (🇨🇦) for American audiences (🇺🇸) with hopes that Open Sauce (🤖) will have fun with the concept.

The model is split into two parts to eliminate the need for annoying brims, since you print the base upside down. This also lets you use spiral vase printing of the top which creates a really beautiful result. You then need a dab of glue to assemble each pin. Pro-tip™; use slow-setting Permabond 240 cyanoacrylate which gives you a few seconds to align the pieces.

I recommend printing these using Vanilla White Prusament PLA.

Print the base using infill to act as ballast. 100% infill will lower the pin's center of gravity making it harder to knock them over. The “nicely tippy" version is slightly taller with a narrower flat spot. I'd recommend this variant unless the floor is particularly uneven or the robots are very high energy (🦺 be safe people!).

Print the top using spiral vase mode to keep the center of gravity low and to also make them look really slick. While it's a pain to have to print these parts one at a time, the spiral prints run really fast. To make the pins super-duper-extra-mega-tippy, print the top part with infill; but I don't recommend this. If you're not careful the pins get so unstable they'll get knocked down just by the vibration of a near miss.

You can fine tune the center of gravity after assembly by using a wide-bore glue syringe and some craft epoxy since the spiral vase print will have a small opening at the top. This isn't necessary but if you are really nerding out with the project and want to get the pin balance “just so” this is how you'd do it.

Finally, I'm not much of a post-processor, but you could dress these pins up rather nicely with an external epoxy coat and some red paint accents. Here's a photo[1] of a regulation 10-pin as a reference:

Robot Bowling

All right. You have your ten pins, let's get bowling!

Find a nice flat and smooth surface to play on with a good lane to bowl down. Concrete works well as do finished wood floors. Setup your pins in a tetractys that is somewhere between 9 and 12 inches a side then bring on the bots 🤖!

I don't have any specific rules here and invite you to improvise and share your own experience. I tried this at my office using a Sphero Bolt with my Canadian Robot Bowling version of this game (being a sphere, Spheros are an obvious choice). The rules of my game were to program steps into a sequence for the Sphero (no direct control) where no step included motion > 30 degrees from down-lane (forward). The fewest maneuvers that knocks down the most pins wins with the least overshoot of the pins being a tiebreaker. Contestants then had to eyeball distances and program one or more maneuvers to take a turn.

You might do something similar with small rover bots like sumo bots, or you could fly FPV drones at the pins, throw tennis balls with a robot arm, or an apple-pie throwing robot (as 🇺🇸-American-🇺🇸 as it gets!). If you're a CV nerd then using an OpenMV sensor to identify pins would be a good variant. As long as you are combining 10-pin bowling with robots you are doing it right.

❤▶🤖&🇺🇸

[1] Bowling pin photo (modified) By User:Michael Barera - From a previously uploaded image which was taken at the International Bowling Museum and Hall of Fame in Arlington, Texas (United States).:International Bowling Museum and Hall of Fame April 2019 31 (Science of Bowling- pins), CC BY-SA 4.0, https://commons.wikimedia.org/w/index.php?curid=78039903