Why CNC Machining is Critical to the Robotics Industry

Why CNC Machining is Critical to the Robotics Industry

Time to read: 5min

Robotic arms

Today, robots seem to be everywhere – working in movies, airports, food production, and even in factories that build other robots. One of the main reasons that robots are so promising is because they can be designed for different purposes and thus have completely different functions. Proleanhub has many years of experience in the machining and manufacturing of robots. This blog will interpretate the meaning and applications of CNC machining to the robotics industry. If you have any manufacturing needs, please feel free to contact our engineers for a free quote.

CNC machining is tailor-made for robots

CNC machining can produce parts with extremely fast lead times. Once you have prepared the 3D model, the manufacturer can start the marking process for CNC manufacturing and purchase the raw materials in parallel. With the help of CNC machining, robot components can be manufactured for rapid deployment, which allows for rapid iteration of prototypes and quick delivery of custom robot parts for specific applications.

Another advantage of CNC machining is its ability to manufacture parts exactly to specification. This manufacturing precision is particularly important for robotics, where dimensional accuracy is key to building high-performance robots. Precision CNC machining can maintain tight tolerances of +/- 0.015mm.

Surface finish is another reason to use CNC machining to produce robotic components. Interacting parts need to have low friction, and precision CNC machining can produce parts with surface roughness as low as Ra 0.8 μm, and even lower with post-treatment operations such as polishing. In contrast, die-casting (prior to any finishing process) typically produces surface roughness closer to 5 μm. Metal 3D printing produces a much rougher surface finish.

Finally, the type of material used in the robot is ideal for CNC machining. Robots need to be able to move and lift objects steadily, which requires strong, hard materials. These necessary properties are best achieved by machining certain metals and plastics, as described in the Materials section below. In addition, robots are often used for custom purposes or small production runs, which makes CNC machining a natural choice for robot components.

Types of Robot Parts Manufactured by CNC machining

With so many possible functions, many different types of robots have evolved. There are a few main types of robots that are commonly used.

Articulated robots have a single arm with multiple joints, which is something many people have seen before.

There are also SCARA (Selective Compliance Articulated Robot Arm) robots, which can move things between two parallel planes. SCARA has a high vertical stiffness because they move horizontally.

Delta robots have joints located at the bottom, which keeps the arm light and able to move quickly.

Gantry or Cartesian robots have linear actuators that move at 90 degrees to each other.

Each of these robots has a different construction and a different application, but there are usually four main components that make up the robot.

1)a robotic arm
2)end-effector
3)motors
4)custom clamps and fixtures

1 Robotic Arm

Robotic arms vary greatly in form and function, so many different components can be used. However, one thing they have in common is their ability to move objects or perform operations on them, and the different parts of the robotic arm are even named after ourselves: the shoulder, elbow and wrist joints rotate and control the movement of the parts in between.

Robotic Arm

The structural components of robot arms need to be hard and strong so that they can lift objects or apply forces. Because of the materials used to meet these requirements (steel, aluminum and some plastics), CNC machining is the right choice. Smaller components, such as gears or bearings in joints, or parts of the housing around the arm, can also be CNC machined.

2 End-effector

An end-effector is an attachment that attaches to the end of the robot arm. End-effectors allow you to customize the functionality of your robot for different operations without having to build an entirely new robot. They can be grippers, graspers, vacuums or suction cups. These end-effectors typically have CNC machined components made of metal (usually aluminum) (more on material selection later). One of these components is permanently attached to the end of the robot arm. The actual gripper, suction cup or other end-effector (or array of end-effectors) fits into this component so it can be controlled by the robot arm. This setup with two different components makes it easier to swap out different end-effectors, so the robot can be adapted to different applications. You can see this in the diagram below, where the functionality of the robot can be easily switched by swapping out the end-effectors.

End-effector: Carton gripper

End-effector: 5-jaw manipulator

3 Motors

Every robot needs motors to drive the motion of its arms and joints. The motors themselves have many moving parts, many of which can be CNC machined. Typically, the machined housing of the motor, the machined bracket used to attach it to the robot arm, and even the bearings and shafts are often CNC machined. Shafts can be machined on a lathe to reduce the diameter or on a milling machine to add features such as keys or slots. Finally, gears that transfer motor motion to robot joints or other parts can be CNC machined by milling, EDM or hobbing machines.

Servo motors for powering robot motion

4 Custom Jigs and Fixtures

Although not part of the robot itself, most robot operations require custom jigs and fixtures. You may need a fixture to hold the part in place while the robot works on the part. You can also use fixtures to precisely position the part one at a time, which is often necessary for the robot to pick up or put down the part. Because they are often one-off custom parts, CNC machining is ideal for fixturing. Lead times are short, and CNC machining is often easily accomplished on a piece of stock material, usually aluminum.

In Summary

CNC machining has been significant to the rapid growth of the robotics industry. It is a great advantage in terms of fast production, high quality, and high surface finish during the production of robot parts. In the robot manufacturing process, CNC machining is often used for four parts: robot arms, end-effectors, motors, and custom fixtures and fixtures. This blog describes the importance of CNC machining to the robotics industry and the application scenarios. If you have CNC machining needs, you can visit our CNC service page or upload your CAD files directly to get the latest quotation.