What is an End-of-Arm Tool (EOAT) in a Robot?

What is EOAT’s meaning? In this article, we will explain the uses of an end-of-arm tool mounted on a 6-axis robot. We will also explain the applications of a 6-axis robot.

In the next article, What is 6-Axis Simulation Software?, we will explain what 6-axis robots simulation software is.

Those who are not yet acquainted with 6-axis robots might not know what an end-of-arm tool is. An end-of-arm tool has many other names such as end effector, claw, gripper, robot tool, and others.

Simply put, the object which connects the robot physically to the work being done is an end-of-arm tool.

End-of-arm tools come in many shapes and sizes, depending on what work needs to be performed.

The part of the robot that the end-of-arm tool connects to is called the faceplate. Each end-of-arm tool is mechanically connected to the faceplate with some sort of hardware.

It’s a good idea to understand how the end-of-arm tool is connected to the robot and regularly perform service on the robot to verify that the connection hardware is tight.

If for some reason the hardware comes loose, it could cause damage to equipment or even sometimes injure workers.

How the end-of-arm tool is powered?

We will now explain how the end-of-arm tool is powered. End-of-arm tools are powered in a few ways.

1) Some use electricity to move servos that are a part of the end-of-arm tool. Servo motors can be used to grip parts and move them from one place to another. When a servo motor is located on the end-of-arm tool, it is called an auxiliary axis.

2) There are also pneumatic devices on a 6-axis end-of-arm tool, which can grip a part using compressed air. Compressed air is commonly used because it’s relatively inexpensive to purchase and operate.

3) Hydraulics can be used depending on how much pressure is needed to close the part.

Whether a 6-axis robot uses electricity, pneumatics, or hydraulics, it is important to route the cables in such a way that when the robot moves it doesn’t smash, pull, or break the wires and lines that go to the end-of-arm tool.

To safeguard the wires and lines some robots have mounting places placed by the manufacturer to route cables.

Some even have hollow spots inside the robot to allow for cables to be run through it.

Swapping the end-of-arm tool

Most end-of-arm tools are fixed, meaning they are attached with hardware and don’t come off except for maintenance or service.

However, there are also changeable end-of-arm tools, which means that depending on the work that needs to be done the end-of-arm tools can be swapped.

For example, you have a piece of wood that needs to be cut and sanded. One tool would hold a saw to cut the wood to the desired length.

When the task is complete the robot would move near where the second end-of-arm tool would be. Then the robot would release some sort of unlocking mechanism to release the first end-of-arm tool, move and connect the second end-of-arm tool.

The second tool has a sander that would sand the surface of the wood.

Having multiple end-of-arm tools can make it more economical to buy a robot when there are multiple tasks to perform.

However, depending on how fast the process needs to go, it might be better to have a second robot perform the task of the second end-of-arm tool instead of swapping the end-of-arm tool.

Different types of end-of-arm tools

We will now explain the different types of end-of-arm tools. We will explain each one of these tools with their associated applications.

1) Pick and place

Robots, that pick up and place, use a way to grab onto the object or some sort of vacuum device to hold on to the object.

1-1) Pick and place – claw

Pick and place end-of-arm tools can look like a claw that opens and closes. Pick and place robots are used for a variety of applications but they are always moving an object from one place to another.

1-2) Pick and place – foam pad

Pick and place end-of-arm tools can also look like a big foam pad.

When the vacuum is engaged, the object is temporarily stuck on the end-of-arm tool until the robot releases the object. These foam end-of-arm tools are used in palletizing applications.

These foam tools offer the flexibility to pick up many objects in many ways. For example, you need to place one large-length box with three small-length boxes. The vacuum foam end-of-arm tools will be able to pick up the different length boxes and neatly place them on the pallet.

Because the foam is flat, the foam on the vacuum tool can use programming to offset the picking and placing of the boxes without any mechanical side effects.

2) Spray gun

There are also robot end-of-arm tools that are used to hold a paint gun for spray applications. These tools allow the robot to coat objects in paint. An example of a spray application is a vehicle that is being sprayed by a robot.

The robot can use discrete outputs to turn on and off the gun for the desired finish. These robots use tubes to get the paint from a reservoir and run it to the end-of-arm tool.

3) Welding gun

Robots, that weld, have welding guns mounted on the robot’s faceplate. This end-of-arm tool allows the robot to weld metal together. The welding gun, like paint robots, can be controlled by discrete I/O so that the weld length can be precisely controlled.

4) Vision inspection camera

Another end-of-arm tool on a 6-axis robot is one that can hold a vision inspection camera. This camera is used for quality assurance for parts with critical specifications.

The robot would move into position and take pictures using the camera that would determine if various parts are in spec or not.

Robots can use pick and place and camera inspections together to track the movement of a part on a conveyor and then tell the robot where to go to pick an object off of the conveyor.

Vision camera systems can also be used for quality assurance functions off of robots.

Summary

6-axis robots have many different tools which help in their respective applications. Whether it be pick and place, palletizing, welding, and spraying.

6-axis robots will help accomplish repetitive tasks.

In the next article, we will explain what 6-axis robots simulation software is.

If you have any questions about the end-of-arm tools, or about robots in general, add them in the comments below and we will get back to you in less than 24 hours.

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