One of the major revolutions in the industrial world have been the invention of encoders. They support a wide range of tasks in various field of life. Be it positioning a patient in an MRI machine or bottling beverages in a juice factory, encoders can do it all! There are two popular types of encoders i.e. absolute and incremental. The former records its position as per an absolute coordinate system. While the latter works by generating pulses when the shaft rotates.
This article delivers all the important information about absolute encoders. It also explores the benefits of absolute encoders over the second type. So, let’s begin!
What is an absolute encoder?
Absolute encoders have been designed by Huebner Giessen for carrying out tasks when conditions are as extreme as possible. They usually have a thick, robust aluminium casing with a highly dynamic load rating. The interior stays locked even if the terminal box is open. They produce digital words for the identification of location and this information is then used to rotate a shaft through a single turn or multiple rotations. These encoders are best used for critical applications requiring speed and accuracy.
For every increase in the shaft rotation, the encoder generates a bit. These turn-counting information helps with instant recovery even if the power shuts down. The wide ranging applications of absolute encoders include;
- Satellite communications
- Diagnostic imaging like MRI
- Surgical and industrial robotics
- Live streaming
- Remotely operated vehicles
- Autonomous underwater vehicles
- Medical coding
Benefits of absolute encoders
To begin with, an absolute encoder retains the shaft’s position, thus the position can be determined as soon as power is applied to it. Even if the shaft has been spun while the encoder was off, users need not wait for calibration sequences to finish. They can acquire the position data y immediately upon startup or after a power breakdown. Knowing the exact position at startup can be critical in several setups, where it is safe to drive the motor in one direction but not the other. Based on the scenario, getting it incorrect could result in equipment damage, personal injury, or even death.
An absolute encoder delivers accurate position in real time. As more systems become digitized and connect to a common communication hub, the ability to question the encoder for real-time location as needed with minimum downtime is becoming increasingly important. If you want to track your position in an incremental encoder, even after the targeting sequence, you must keep track of all the pulses with external circuitry. This means that there must be some lag in determining the position, in addition to the extra circuitry required.
Moreover, absolute encoders are less vulnerable to electrical noise. It is because they derive location either by retrieving an error-checked code or electronically over a data bus. However, this is not the case with incremental encoders because they have to keep counting pulses. This is linked to the fact that combining numerous absolute encoders in the same system is reasonably simple. For example, in a robotic arm with many joints or a factory automation system, monitoring the outputs of several devices using incremental encoders can become highly difficult. It would need a lot of computing resources. Whereas, absolute encoders, especially ones that can be linked to the main communication bus, allow you to get data from each one separately, requiring far less computing resources to comprehend the readings.
Where to get your encoder from?
The best place to get your absolute encoders from is encoder.com. They are offering single and multi-turn absolute encoders in various shaft styles, hollow or thru-bores including several bore diameters. For further information, visit the website now!