Candy sorting robots are in abundance on these pages, and for good reason – they’re a great test of the full suite of hacking tools, from electronics to machine vision to mechatronics. So we see a lot of sorters for Skittles, jelly beans and sometimes even Reese’s Pieces, but it still seems like M&M sorters are the most popular.
This M&M sorter has a twist, however – it finds the elusive and coveted peanut-free candy that lurks in most Peanut M & Ms. bags. To be honest, we would never have encountered this manufacturing flaw before; being mainly devoted to the original old M & Ms, maybe our sample size is just too small. Independently, [Harrison McIntyre] knows they’re there and wants them all for himself, hence his impressive build.
To detect squib confections, he built a tiny 3D scanner from a line laser, a turntable and a Raspberry Pi camera. After scanning the surface to give its volume, a servo sweeps the candy. on a scale, allowing the density to be calculated. Peanut-free candies will be a bit denser than their legume counterparts, allowing another servo to move the candies to the appropriate outlet chute. The video below shows you all the details, and more than you ever wanted to know about Peanut M & Ms. population statistics.
We think it’s quite stylish, and a good start from sorters that rely primarily on color to sort candy. Of course, we still love them too – take your pick quick and easy, compact and elegant, or an industrial design model.