Lego Mindstorms EV3 Candy Circles

[Hanso]

This article about the new Candy Circles, is related to two other threads of mine:

1) The Lego Candy Sorter

2) The Lego Candy Warehouse

 

The new developed Lego Mindstorms EV3 Candy Circles are replacing the Candy Sorter. The color detection of the Candy Sorter was simply not reliable enough. Once calibrated, it worked fine but it was too sensitive for a change in light. Therefore, it was not good enough to perform for a longer time, e.g. at Lego World or during another demo.

We decided to go back to manually sorting the candies. But then we still needed some dispense mechanism to release a candy, that would be stored in the Candy Warehouse.

I came up with the following solution:

• Four large circles, containing the candy.
• A circle would be able to release one candy at a time.
• The released candy would then be transported to the Trebuchet (where the candy would be put in a container, and then the container with candy is stored in the Candy Warehouse).

This was the first prototype:

As you can see, there is a touch sensor and one marker added onto the ring. The marker was used to sync a full rotation. After the sync, I would just rotate the ring 360/16 degrees to release the next candy. Because there is always a bit of drift, the sync (per full rotation) was planned to make sure that the drift could not increase infinitely.

 

But, of course it would be better to stop exactly at each bucket. So I made a second proto.

As you can see, each bucket has its own marker to stop exactly at the right position. This proto was good enough to start building four circles. And a matching conveyor belt.

 

This is the result:

And of course a video:

 

Next step to make: how to determine that a candy circle is empty? I don't have free ports to add an additional sensor. And of course it needs to be reliable!

Will keep you posted.

-- Hans

Edited July 31, 2019 by Hanso

[Hanso]

BTW: More photos of the Candy Circles can be found here: flickr.com/photos/siouxdotnetontrack

 

Edited August 1, 2019 by Hanso