What’s EoAT (end of arm tooling) for robots?

End of arm tooling refers to the different tools used by robots or robotic arms to interact with objects, parts, or components. The term is very large, as it can cover anything from sensors to grippers and other tools – whatever can be put at the end of a robotic arm.

EoAT is an essential part of manufacturing processes. It’s what enables robot pickers to grab objects on a conveyor belt, for example, or automated 3D scanning arms to capture quality control data.

XYZprinting HARBEC case study end of arm tooling

Optimizing end of arm tools at HARBEC

HARBEC, a well-established company based in the state of New York, manufactures thousands of parts per month using a range of technologies: CNC machining, injection molding, and 3D printing are all part of their offer.

Like many manufacturers and providers of their stature, HARBEC’s factory floors are equipped with robots to move parts from one station to another. These robotic arms require special end of arm tools like claws or grippers depending on the parts they’re working with.

More specifically, and this is where the 3D printing part comes in, each EoAT needs its own bracket in order to be articulate and hold onto the arm.

With their 20+ years of experience in additive manufacturing, HARBEC decided to use 3D printing to produce these tailored brackets, especially to reduce their weight via topology optimization. The lighter the parts are, the less strain there is on the arms, and the quicker the robots can move.

Stereolithography vs Selective Laser Sintering

HARBEC’s engineers initially used stereolithography (SLA) to produce their bracket. However, after optimizing the bracket’s design to make it more lightweight, the resulting parts weren’t rigid enough.

In order to keep the part as lightweight as possible all while maintaining sufficient strength, the team decided to switch to SLS (Selective Laser Sintering) technology via their XYZprinting MfgPro230 xS.

After several trial-and-error tests, HARBEC realized that they had made the right choice. The brackets produced with SLS technology and PA 12 materials proved to be almost just as stiff as the non-optimized brackets, all while being up to 50% more lightweight and maintaining the required dimensional accuracy.

Here are the different results they obtained:

Result 1

HARBEC 1 SLA Accura 25 100g
  • Technology: SLA
  • Material: Accura 25
  • Weight: 100g
  • Ultimate Tensile Strength: 38 MPa
  • Young’s Modulus: 1590-1660 MPa
  • Results: Heavy, Rigid, High Yield Strength

Result 2

HARBEC SLA Accura 25 60g
  • Technology: SLA
  • Material: Accura 25
  • Weight: 60g
  • Ultimate Tensile Strength: 38 MPa
  • Young’s Modulus: 1590-1660 MPa
  • Results: Heavy, Flexible, Low Yield Strength

Result 3

  • Technology: SLS
  • Material: PA 12 (XYZprinting)
  • Weight: 50g
  • Ultimate Tensile Strength: 38 MPa
  • Young’s Modulus: 1700-1800 MPa
  • Results: Lightweight, Rigid, Moderate Yield Strength

Final tool

This is what the final tool looks like, fitted with the gripper mechanisms:

HARBEC SLS PA12 XYZprinting Final part

A closer look at the XYZprinting MfgPro230 xS

The MfgPro230 xS is one of the most cost-effective plastic SLS solutions currently on the market. It has been gaining popularity this past year, and is put to use for a wide variety of applications.

XYZprinting MfgPro230 xS
The XYZprinting MfgPro 230 xS.

These are a few of its main features:

  • Large build envelope: 230 x 230 x 230 mm
  • Build speed: Up to 20 mm/hour (geometry dependent)
  • Available materials: PA 12 (rigid), TPU (flexible)