For experienced robotics engineers in the automation industry, choosing the right robot is probably a manageable responsibility. For some planners of automated factories, who need to buy robots for the first time, this can be a bewildering assignment. What to know and how to select the right type of robot based on several parameters?
The key is first to evaluate the variety of applications and the type of processes used by the robots. The Cooperative Robot (Cobots) is usually a suitable option if the application process is applied to the standard semiautomatic as well as mixed man and machine assembly line. Particularly in situations where a change in the work position is required the use of a robot with a torque sensor is useful.
If you happen to look for a high-quality pick and place robot, then SCARA and DELTA are excellent choices. They work on horizontal assembly lines and can rapidly pick and insert small objects.
The most amount of load that the robot can carry is known as the payload. It can vary a lot from few to hundreds of kilos. If the situation demands that the robot is going to move parts from one workbench to another, you would have to take the sum total of the weight of the piece and the gripper that the robot uses as payload.
To achieve movement in the desired manner the robot has to swing around. This would involve three axis – horizontal, vertical and depth of movement – and also rotation. Not only are industrial robots capable of moving on multi-hinge joints but have different arms that are capable of rotating in various ways to provide up to 7 different directions of travel. The more the direction of travel or axis the higher is the cost since the robot is more flexible.
Robot joints have different names depending on their distance from the base of the machine. These are designated as J1, J2, J3 and so on.
Also known as operating range it is an essential criterion. Due to the robot being, in essence, a lever the longer that it reaches, the greater does the stress due to payload become. The robot needs more power to reach 10 kilos across 3 meters than to reach 15 kilos across 1 meter. The range of travel, therefore, influences the power of the robot. This is complicated by the fact that it has to reach across in 3 dimensions and the stress on various joints are multiplied.
The robot has to not only reach across with its payload but also place it correctly. Since robots work many times faster than humans, it is vital that it inserts the payload at absolutely the right position. If there is an error in one station due to wrong placement, it will shut down all subsequent stations.
These are only a few of the items to consider before buying a robot. Since a robot is a substantial investment, it is essential to understand the requirements very carefully before making the purchase decision. A well-informed buying decision can save years of headache and millions of dollars through the life of the assembly line.