The axis of a robot is commonly known as a joint, which is like a human arm. Of course, the more joints, the more flexible they are, and the more positions they can rotate and reach. This seems to need no explanation!
1. Six-axis robot
However, we can't say that the more axes the robot has, the better. Why? Now explain it slowly!
The more the number of robot axes, the more complex the robot control system, the higher its cost, the more points that can be reached in 3D space, and the relative flexibility is beyond doubt. From this point of view, the more the number of robot axes, the more advanced is correct, but not the better. Why?
2. Six-axis welding robot+external axis=7 axis
Case 1: Stacking application. In the application of palletizing, the goods do not need to rotate in a three-dimensional way. The goods themselves only rotate in a horizontal direction, and the placement is only different from the front and the right. Therefore, the four-axis palletizing robot is enough to complete these actions. If the six-axis robot is selected, it will increase the pace of palletizing. The number of palletizing times of the four-axis palletizing robot is generally 1000 times/h, while the fastest of the Kuka six-axis robot is 700 times/h, In addition, the six-axis robot with the same load is much more expensive than the four-axis robot. Can we say that the six-axis robot is good?
Case 2: The scara robot has only three axes, and its working range can only be in the horizontal plane, but the working rhythm is much faster than that of any six-axis robot. Generally, the combined speed of the XY axis of the scara robot can reach 5 m/s, the Z axis (up and down) can reach 1.6 m/s, and the maximum linear speed of the Kuka robot (the best robot recognized in the world) is 2 m/s. Can we say that more axes are better?
Case 3: DELTA robot is a three-degree-of-freedom parallel robot, its working rhythm can reach several times/second, and its repeated positioning accuracy is far higher than that of six-axis robot. Can we say that more axes are better?
To sum up, industrial robots should be suitable for use. Now, robots are classified according to different working conditions:
1. Generally, four-axis stackers are used for stacking, with the advantages of large load and high speed.
2. For general welding, six-axis small-load robots, such as 6kg robots, are generally selected, because the robot only needs to carry the weight of the welding gun and wire feeder, and the 6kg load is sufficient. The difference in model selection is the length of the robot arm, that is, the working range, usually 1200mm, 1400mm, etc.
3. For butt welding, such as the spot welding of automobile shell, the six-axis robot with large load is generally selected, because the robot needs to bear the weight of welding tongs.
4. Generally, six-axis robots are used for spraying, polishing, loading and unloading, and robots with different loads and arm lengths can be selected according to working conditions and working range.
5. Scara robot is generally used for electronic device assembly, which is fast and accurate.
6. For food packaging, sorting, etc., delta robots or scara robots are generally selected, with high speed and accuracy.
Therefore, in the actual industrial application level, it is not the more the number of axles is better, but the actual use. Some look at speed, some look at accuracy, some look at load, some look at arm length, and different brands focus on different directions. For example, the same brand, 165kg robot should be a little more expensive than 50kg robot, but some brands may focus on heavy load, while 50kg robot is rarely produced, Then it is possible that its large load is cheaper than the small load, and the lack of mass production is an important factor. Therefore, it is necessary to compare the selection of robots. Especially this year, the endless emergence of domestic robots also has a certain impact on the entire market. We should have a correct understanding!
