Sausage cutting machine

Sausage cutting machine

When grilling sausages you usually want to slice some cuts to the surface. This is especially true if the sausage cooked on a stick as otherwise the sausage might rip open uncontrollably and fall of the stick. The cuts also promote optimal browing and crispiness and are therefore necessary for the enjoyable sausage experience.

However, one might grow tired to slicing the sausages by hand. Especially those who like to have lot of small cuts.
For this we present the solution:

Disclaimer: We wouldn't eat the sausages as the parts are not necessarily food-safe! Therefore, the grilled sausages shown at the end of the video are not made with the machine.

The machine has two stepper motors controlled with Urumbu and one servo controlled with a microcontroller (XIAO RP2040).

All 3D printed and laser cut parts were designed by the team. Other necessary hardware and devices are listed below in the bill-of-materials.

Source files

• The original design was in Fusion 360 but the file would be too large. This STEP file has everything but the stepper motors which increased filesize.
  • 3D model of the parts assembled
• 3D printable files (.step):
  • Base
  • Stick holder
  • Cutter holder
  • Blade holder
  • Top support
• Laser cuttable files (.svg)
  • Initial design walls
  • Stepper collet
  • Sausage stick support
• Code
  • Microcontroller code
  • Modsproject.org program

BOM

Item	Purpose	quantity
Stepper motor NEMA17	Rotate sausage and threaded rod	2
Urumbu boards	Control Stepper motors	2
Positional rotation servo	Cutting action	1
Threaded rod	Raise/lower cutter	1
5 mm metal rod	Support cutter	1
M3 bolts	Attaching motors	20
Razorblade	Cutting tool	1+
4 mm grill stick	Hold sausage	1+
3-5 mm plywood	Support pieces	< 100 cm&sup2
PLA	3D printed parts	60 cm&sup3 / 75 g

Initial sketches

The original vision was basically an egg plotter but longer and pen replaced by knife:

First prototype

We started with a 3D printed base and built on top of that.

Testing

We made some initial testing with the first prototype. It seemed to work to some extent, but more work would still be needed.

For example, the machine needed to be more rigid.

Controlling the motion

We used Mods Community Edition to control the motors that spin the sausage and move the cutter in vertical direction.

We improved the design to make it more robust and lightweight. The latest version is shown here:

Second design iteration

For the second iteration, all parts of the design received atleast some changes or were replaced completely.

Problems faced & solved

1. The blade would not be sharp enough to simply be pressed in the sausage unless the machine was exessively rigid.
   • Solution: Keep the sausage spinning so the blade slides along the surface.

2. Our lab only had very short or very long M3 bolts.

   • Solution: Improvise, cut bolts to desired lenght.