The Basics of Servo Drives & Their Applications
In the world of science and technology, there are few things more important than machinery. Without precision, equipment breaks down, experiments fail, and wrong conclusions are drawn. Because of this, machinery needs to be able to work as precisely as possible.
That’s where servo drives come in. Understanding the basics of servo drives and their applications is the key to ensuring your technology achieves the highest degree of accuracy possible.
What Is a Servo System?
A servo system is an automated closed-loop system designed to facilitate precise movements. The system has several parts, including:
- An interface panel where a worker inputs a command
- A controller where that input is received and converted into data that can be used by the system
- A drive or amplifier that takes the command and amplifies it into high-voltage messages for torque, power, and speed
- A high-power motor that provides exact movements
- An encoder that is attached to the back of the motor and provides feedback to the rest of the system based on position
- A mechanism that is powered and moved by the motor
The encoder is behind the precision of servo systems. In open-loop systems that do not include encoders, the system continues working regardless of the outcome. Think of it as a heater that continues to heat water indefinitely until the user turns it off manually.
In a closed-loop system, an encoder monitors the output and feedback to the system so that the whole system can adjust its actions accordingly. This would be like a heater that heats water up to a predetermined temperature, then automatically shuts down once it reaches said temperature.
What Is a Servo Drive?
But the encoder is not working by itself. This is where servo drives come in. When the encoder takes feedback in, it sends these messages back to the drive. The amplifier then takes this information, processes it, and sends messages back to the encoder to control the motor’s speed and position.
In some instances, a servo drive may be combined with a servo controller in order to reduce the space taken up by the servo system.
Applications of Servo Motors
This technology, though simple in a sense, has a wide variety of uses and can be found in both highly specialized technology and machines you may encounter in your everyday life.
Being able to cut raw materials and metal into precise shapes is essential in the manufacturing industry. Otherwise, parts of machines will not fit together correctly, leading to machinery that is faulty at best and dysfunctional at worst. Servo systems are applicable for any equipment used in the process of creating these parts, including:
- Milling machines
Servo systems are also highly involved in computer numerical control (CNC) machining, which is one of the most crucial processes in manufacturing today.
In the material handling industry, more and more warehouses are turning to automation to help improve workflow and efficiency. Some automation systems include a goods-to-people (GTP) picking systems in which autonomous robots help move products from shelves to workers.
Since most customers prefer not to have their products crushed, precision is of the utmost importance when it comes to how these machines pick up and carry items. That’s why having a servo system in place is key.
Antenna Positioning Systems
It’s easy to associate satellites with highly specialized scientific functions or bad television reception. But satellites are a key part of a myriad of our everyday tasks, such as:
- Weather monitoring
- GPS and other navigation systems
- In-flight communications with airplanes
- ATM transactions
None of these systems can function without antenna positioning systems that accurately angle satellite dishes skyward, and these systems must be autonomous. Servo drives are able to help position the satellite dishes while shifting according to feedback from the system.
We often take for granted how easy it is to get a camera to focus when taking a picture. These days, cameras come equipped with autofocus, which adjusts the distance between the lenses of a camera until you have a perfectly focused image.
For a function like this to work properly, you need a system that can make the smallest movements and adjust them on the fly depending on the feedback you are getting from the image. Servo drives meet that need and can be found in most cameras with autofocus.
Print technology has come a long way from the printing press. Digital print technology has allowed for greater speed and accuracy for even the most complicated jobs. 3D printing has allowed us to print everything from phone holders to prosthetic limbs.
Both processes (but 3D printing especially) require continual feedback between the computer and the printer itself in order to accurately render the image or object. This is another opportunity for servo drives to shine, and they can often be found on the extruder of 3D printers.
An explosion is an incredibly powerful force, and because of this, it can grow out of control very quickly with deadly consequences. Even so, a surprisingly wide variety of industries utilize explosives regularly, such as:
- Fire fighting
- Avalanche control
- The military
Harnessing the power of explosions without allowing them to grow out of control is a delicate science that often requires robots with refined bomb detonation technology. Many of these robots use servo drives in order to ensure the machines are using the most precise movements possible.
Despite the great number of people who have a fear of elevators, there hasn’t been a reported elevator free fall since 1945, and for good reason. Elevators are built with a plethora of safety functions, including cables that can each hold the weight of a car and specially designed safety brakes.
Servo motors also act as an additional safety feature for elevators by helping ensure accurate movements throughout the ride. Servo systems also help monitor the speed of the elevator as it travels.
Science and technology are always marching forward, and understanding the basics of servo drives and their applications is only the beginning. Here at Industrial Automatons, we have quality CNC servo drives that work in a variety of systems.