Maraschino Machine

This is the Maraschino Machine, a four-bar driving a five-bar linkage system that garnishes your Shirley Temple. Once you set your cup down, the machine spears a cherry and swings down to your glass before gently depositing it.

Motion Gen

  • Modeled our design in Motion Gen to design the path our end effector would follow.

  • Original design included a mirrored four-bar that would slide the cherry off the end effector when they overlap.

Kinematic Analysis

  • Performed kinematic analysis in Python by creating a simulation of the system.

  • Used this to find the velocity and mechanical advantage of the end effector at each point along its path, as displayed in the graphs to the right.

  • This validated that our machine would approach the cherry at a controlled speed and spear it with enough force to pierce the surface.

CAD - Onshape

Front View

Rear View

  • CADing the system was very important to make sure none of the links would intersect and that the machine would follow the path we expected.

  • Wanted as few layers of links as possible to keep the system compact and reduce lateral play.

  • At this point we decided to remove the lower four-bar to reduce the strain on the motor and layers of links.

  • We incorporated slots along all of the mounting points to allow for easy assembly and repair.

  • The purple slide mounted to the frame is designed to hold up to seven cherries for repeated use.

Electronics

  • 12V wall plug for power supply, incorporates a button to act as an E-Stop.

  • Pressure plate with button underneath to activate the machine when you set your cup down.

  • An Arduino and DC motor driver are used to control the system.

Final Assembly

Front View - Pickup Position

Front View - Deposit Position

Top View

End Effector Close-Up

  • Built with 1/4” plywood acrylic, and 3D printed parts.

  • Shaft collars and spacers to keep each layer in place.

  • Used press-fit bearings and steel shafts at each joint to reduce friction and ensure a secure fit.

  • Needed something thin, rigid, and sharp to spear the cherry, so we chose a tooth pick as our end effector.

  • Created a small shelf that would allow the toothpick to continue its path while forcing the cherry to fall into the cup.

If you’d like to learn more about our project in detail, here’s a link to our final report