End-effectors have many other names, such as end effectors, grippers, jigs, and robotic tools. Simply put, an end-effector is the object that physically connects a robot to the work being performed. End-effectors vary in shape and size depending on the task at hand.
The part of a robot that connects to the end effector is called the panel, and each end effector is mechanically connected to the panel via some kind of hardware. If the hardware becomes loose for any reason, it may damage the equipment and sometimes even injure the worker. Therefore, understanding how the end effector connects to the robot and regularly maintaining the robot to ensure that the connection hardware is secure is essential.
Power supply method for end effector tools
1. Electricity: End-effectors operate in various ways. Some robots use electricity to drive servo motors on the end-effector. These 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-effector, it is called an auxiliary axis.
2. Pneumatic: The six-axis end effector also has a pneumatic device, which can be used to clamp parts using compressed air. Compressed air is commonly used because it is relatively inexpensive to purchase and operate.
3. Hydraulic: Of course, a hydraulic system can also be used depending on the pressure required to clamp the parts.
Whether a six-axis robot uses electricity, pneumatics, or hydraulics, it is important to lay out the wiring in a reasonable manner so that the wires and cables connected to the end effector are not crushed, pulled apart, or damaged when the robot moves. To protect the wires and cables, some robot manufacturers provide installation locations for the wiring, and some robots even have internal openings so that cables can pass through.
Robot end-effector quick-change device
Most end tools are fixed, meaning they are attached to the hardware and will not come off except for maintenance or repair. However, there are also replaceable end tools, meaning that the end tool can be replaced as needed to perform the required work.
For example, you have a piece of wood that needs to be cut and sanded. One tool will hold a chainsaw to cut the wood to the desired length, and the second tool has a sander to sand the surface of the wood. Once the first task is completed, the robot will move to the vicinity of the second end effector. Then, the robot will release the first end effector, move, and connect to the second end effector.
Having multiple end-point tools allows for more precise selection of robots when multiple tasks need to be performed.
Types and application scenarios of end-point tools
Six-axis robots have a variety of end-effectors that can help them perform operations such as picking and placing, palletizing, welding or painting in their respective applications.
1. Grippers/Suction Cups
When picking up and placing objects, robots can use a gripping method or a suction cup device to hold the objects in place. Pick-and-place end effectors resemble a claw that can open and close. Pick-and-place robots are used in various applications, but they always move an object from one place to another. It can also resemble a large foam pad. When vacuum-adhesive is applied, the object temporarily adheres to the end effector until the robot releases it. These foam end effectors are used in palletizing applications. These foam tools offer the flexibility to pick up multiple objects in multiple ways.
2. Spray gun
Another type of robotic end-effector is used to hold a spray gun for painting applications, enabling robots to apply paint to objects. An example of a painting application is a robot painting a vehicle; the robot can use discrete outputs to control the spray gun's on/off state to achieve the desired coating effect. These robots use tubing to draw paint from a reservoir and deliver it to the end-effector.
3. Welding gun
The welding robot has a welding gun mounted on its panel; this end-effector allows the robot to weld metal together. Like the painting robot, the welding gun can be controlled via discrete I/O, allowing for precise control of the weld length.
4. Visual inspection camera
Another end-effector on a six-axis robot is one that can be equipped with a vision inspection camera. This camera is used to inspect parts with critical specifications to ensure quality. The robot moves to a designated location and uses the camera to take pictures to determine if each part meets specifications. The robot can simultaneously use pick-and-place and vision inspection to track the movement of parts on a conveyor belt and be told where to pick up parts from the conveyor belt. The vision system can also be used for quality inspection functions beyond the robot itself.
