Many industrial automation tasks can be done by SCARA robots. These four-axis robots can perform pick and place applications, small assembly tasks, screw driving, dispensing and more. They’re ideal for applications that require a high level of precision.
A scara robot is able to achieve high speed and rigidity because it has a beltless structure and direct-drive servos. This gives them an overwhelming advantage over other robot types because it eliminates belts and chain drives that can cause friction, wear and vibration. This also makes them more resistant to shock and impact than cartesian robots.
Another difference between cartesian and scara robots is their work envelope. Unlike cartesian robots, which have a rectangular work envelope, SCARA’s are circular making them more compact and suitable for smaller spaces. Clark says he likes to use the analogy of an office chair when explaining the difference between these two types of robots. When a cartesian robot moves forward and backward, it’s much more like moving the chair’s seat back and forth. However, when a scara robot moves up and down, it’s more similar to moving the arm in and out of the desk.
Since all joints of a scara robot are at the end of the arm, they’re less flexible than cartesian robots. This is because they’re able to read forces in their joints and can adjust accordingly. As a result, they can avoid collisions and maintain a precise motion even under extreme conditions.
As with other robotic systems, the payload and inertia of a SCARA robot’s end-effector must be within its operating specifications to ensure proper performance. Fortunately, manufacturers produce a number of different models to suit specific needs. For example, Epson offers a variety of four-axis SCARA robots with different horizontal arm reach lengths (450mm, 550mm and 800mm). These robots can also be customized to fit different environments or applications by integrating various features. For instance, a hose or tube can be fitted to a robot’s nozzle for pressurized application of chemicals. Other options for customization include ingress protection requirements, operating temperature and ratings for food grade, collaborative or explosion proof.
Once a system is suited to a particular application, it’s important that its control be robust and easy to program. One way to do this is by using a machine controller to solve the robot kinematics internally and drive individual servos. This enables the system to run more efficiently, as well as reduce programming costs.
A SCARA robot can synchronize with conveyors to track and handle parts as they pass by, making them an excellent choice for feeder applications. This can be especially effective when a vision system is used to detect and trigger the robot to handle parts based on their positioning in the hopper. As a result, the feeder can have perfect synchronization with the conveyor, which leads to more efficient handling and feeding. In addition to reducing programming and installation costs, this can help to improve part distribution and overall production efficiency.