After buying a cobot, you realize that you have to decide which end of arm tool (EAOT) to purchase. An EAOT depends largely on the type of material. Weight and shape of the parts the cobot handles. Grippers or end of arm tool consists of vacuum cups or magnetic grippers, pliers or finger assemblies. To ensure the cobot works effectively, you have to ensure you choose the right end of arm tool. You should consider several factors before choosing an EAOT:
The Cobot’s Task
The industrial robotic arm greatly depends on the cobot’s work. The end of arm tool or gripper varies fromthe task that the cobot should perform determines the type of gripper. A high-speed loading or unloading task requires the cobot to have vacuum cups, whereas a slower and more precise process requires fingers or pliers to enhance accuracy.
The cycle period refers to the speed the cobot’s arm needs to clamp down or open and close. The cycle period determines the acceleration and the ensuing force from the end of tool arm. A massive gripper puts more stress on the cobot and this causes its parts to wear out. Grippers are now leaning heavily on the use of parts made from hollow aluminum. This is because the more the gripper weighs, the less weight exerted from the end of tool arm.
The level of precision need depends on the type of work. Processes that include some sorting require a griper that ensures the parts are sorted. This is especially if the parts differ in sizes or are placed away from each other in different positions.
Not all grippers are made for the same process. They vary from industry to industry. For example, in the pharmaceutical and food industries, hydraulic grippers are not allowed due to oil spills and contamination risks. In cleanrooms, pneumatic and vacuum grippers are forbidden, as chances of them creating particle flow in the air are high. The grippers found in areas like welding and foundries have high exposure to dirt. Care must be taken to protect them from particles and dirt. Chemical and nuclear environments must take care to prevent corrosion of the gripper to preserve its safety and stability.
Proper knowledge of the manipulatable parts is pivotal in the determination of the gripper you should use for your cobot.
The main factors to consider are:
All grippers, except vacuum cups, should grip angular or parallel closing parts. The larger the parts, the more reach the gripper’s fingers need. In every case, the gripper needs to have sufficient reach to handle the parts. The reach, however, must not be too much. Longer fingers create more revolutions on the gripper and cobot.
The object shape also tells a lot about which grasp types possible. A magnet or vacuum gripper can handle a flat surface. Jaws, multiple fingers or magnet grippers can handle various types of surfaces
A gripper needs to have sufficient force to counter the parts’ weight to ensure the grip holds. Simultaneously, it times how much acceleration it can take during the entire process. You cannot use extreme force to clamp down because the parts or gripper might get damaged.
When estimating the gripper grasp, it is important to consider the surface the gripper works on. The clamping force is calculated by accounting for the weight of the part, highest acceleration while the process is in action, the stress the gripper and the part can take, and the surface’s friction.
The end of tool arm is an essential part of the cobot. You have to make careful consideration while choosing one. The gripper should be adaptable and flexible. This way, you can better adjust the angle, the torque, the position of the clamp and gripping methods. These adjustment cobots will work well to protect your cobot and reduce your retooling expenses in the future.