Cobot grippers are also known as end effectors and are an essential consideration when determining which cobotwill work best for a particular application. A welding robot end effector is very different from the end effector of a pick and place robot.
Similarly, depending on the application you want to automate, you will require a specific end effector.
Cobot grippers cannot be classified under one giant classification because so many factors determine the end product. There are however three critical criteria under which collaborative robots’ grippers fall.
1. They Gripper’s Type of Motion
The type of motion can either be parallel or angular.
a) Parallel End Effector
As the name suggests, with this kind of gripper, the several fingers making up the gripper will approach the object while remaining parallel to one another.
Parallel end effectors are the most common design available,and they can be used in uncountable applications as long as the object to be gripped has a uniform shape.
b) Angular End Effector
An angular gripper is the opposite of a parallel gripper. That means the severalfingers making up the gripper approach the object to be gripped at different angles. It could be 30 degrees, 40 degrees,and even 80 degrees.
Usually, one can adjust the angles of this kind of gripper to the desired angle. Used for objects with an unusual shape and objects that are rather large and hence require a gripper whose angle isn’t limited.
2. The Gripper’s Number of Fingers
a) 2 Fingers
The simplest and most common kind of gripper in regards to the number of fingers as it is suitable for a wide range of applications.
One should note, that amongst grippers with two fingers one can also find some variations. For instance, you can see a cobot with an end effector that picks up objects by inserting the two fingers in a hole or an end effector with pressure control.
The critical thing to remember is that cobots with two fingers will probably apply to almost any application you wish to automate.
b) 3 Fingers
A 3-finger end effector has three fingers. They are not very common in the market but are quite useful for applications that require delicacy and precision.
A 3-finger end effector is also perfect for picking up many objects at the same time. An excellent example of where a cobot with three fingers is useful is in the handling of long tubes because of the increased alignment they offer.
c) Flexible Fingers
As the name suggests, this end effector has flexible fingers that attempt to mimic human movement. They are relatively new in the marketand are perfect for picking varying objects.
Though these end effectorsare limitedregarding the weight and volume they can handle, they are also perfect for applications such as handling food due to the delicacy and flexibility required.
3. The Gripper’s Actuation
Actuation means to set in motion. Regarding actuation, a gripper can be actuated by electric motors, pneumatic valves or hydraulic valves.
When an electric motor actuates an end effector, it means electric motors set off the movement of the gripper. Therefore, the power required is electricity.
With a pneumatic actuator, the source of power is usually compressed air which is converted into energy.
With a hydraulic end effector, the source of power is a fluid motor that uses hydraulic power to facilitate movement.
A gripper’s actuation determines a number of things but most important is the price and efficiency. Understanding the three types helps you decide which will work best with your budget and will enhance the effectiveness of the application.
There are other various ways to classify cobot grippers,but the above three criteria provide a foundation upon which all other classifications are set.
Understanding the classifications will give you a starting point in your cobot purchase journey.