Making a stepper motor move is easy with an A4988 driver. They’re super straightforward and very versatile, making them very popular for 3D printers and other DIY CNC machines.
The nozzle works, the pump works, and it all moves via IRC. The new nozzles from @Aidan Leitch solve an earlier problem with hard plastic nozzles that had no grip or compliance. Yay! Great video, Aidan!
Of course the source of most problems is other solutions. With this new nozzle I’m forced to design a new method to raise and lower the nozzle onto the pieces. This first draft
was a strong start. Sadly it let air leak in from several places and over time it started to slouch on one side. Later it occured to me that if the nozzle tries to pick up a piece attached to other pieces, it would probably pick them ALL up. So there needs to be some kind of ring around the nozzle that keeps other pieces on the table. Maybe also a software rule that says sideways movements are forbidden when the nozzle is down.
@Dan Royer enlisted my help in making a soft suction nozzle for the JigSolve. I utilized many of the same techniques and experiences from my soft robotics projects. The result was four nozzles with varying cup sizes. These were the outer diameters of the cups:
- 7.5mm OD
- 10mm OD
- 12mm OD
- 15mm OD
Each one was 20mm tall. They were casted in 3-part 3D printed molds with Ecoflex 00-50 silicone, but almost any RTV silicone would have worked. All nozzles came out quite nicely and the gripping strength scales roughly with the cup size. I made an Instructables guide and video detailing how I made the nozzles:
Instructables Guide: http://www.instructables.com/id/Silicone-Suction-Grippers/