To understand the makeup of an Absolute Shaft Encoder, we first need to understand what an encoder is and how it relates to being an Absolute Shaft type. Firstly, encoding is the process of converting information data from an initial format to a new data format, mostly for security purposes or information transfer format needs. The information transfer format needs to apply to data that can only be transferrable in a specific format type. Thus, an encoder is the device that facilitates such information conversion processes. The article takes an in-depth look at the Absolute Shaft Encoder and its contribution to the robotic industry. We first need to understand how the terms Shaft and Absolute fit with an Encoder.

Defining a Shaft?

In Motion engineering terms, a machine-produced power can only be transmitted to a power-absorbing machine if a shaft facilitates such a transmission. Thus this rotating machine element, Shaft, of a circular cross-section area is the bridge between the Power-produced and the Power absorbed. Such type of Shaft is called a Transmission Shaft. If the Shaft only functions as an integral robotic part, then it is a Machine Shaft. A Shaft Encoder is Synonymous with a Rotary Encoder.

What is Absolute?

When an encoder loses Power, the shaft position information is under the maintenance of an Absolute Encoder. The regain of Power immediately unveils the Encoder’s Shaft position. The system’s position accuracy maintenance does not need to recall an initial calibration point. Thus at assembly, a set relationship between a controlled robot’s physical position and encoder value exists. Therefore, the free-willed position representation of the Shaft Encoder within some revolution is what defines the absolute part of the Absolute Shaft Encoder.

Absolute + Shaft + Encoders

Different mounting styles exist for different encoders. Positional feedback is the output of the motor-mounted encoders. When speed and positional accuracy is a requirement, the Absolute Shaft Encoders step up. Thus applications that demand high resolution and little fail tolerance are ideal for the Absolute Rotary Shaft Encoder. Such applications include homeland security, aerospace, military, oil & gas, and medical field sectors. High reliability, low weight, low profile, and high-resolution & precision combinations are the ideal functional conditions of an Absolute Rotary Shaft Encoder.

Since rotating shaft positional information over a single or multiple turns/rotations is the responsibility of the Absolute Encoders, a unique digital code represents each Shaft rotation increment. The unique code is more of a digital signature that distinctively identifies the position of the encoders at any given moment. The turns-counting information storage is by the multi-turn Absolute Encoders and is useful during the retrieval of the same information even during a power loss incident. The multi-turn and single-turn Absolute Shaft Encoders are both recognized under the industrial EPC (Engineering Procurement and Construction) contractual arrangement. Their representation is of different resolution, signal types, shaft diameters, and housing sizes. Let us consider some of the encoder models within the global industry.

Model A36SB Absolute Shaft Encoder

It is characteristic of a serial communications package under a 36 mm unit defined multi-turn shaft solution.

The model grants your absolute feedback needs in terms of a high-performance solution. Its multi-turn technology is innovatively gear-free and battery-free. It thus makes it very assistive in its provision of maintenance-free feedback. The encoder suits applications that critically need position information after system power loss. Harsh industrial environments make the Model A36SB a suited candidate due to its high IP rating and rugged magnetic technology. The Model A36SB is easy to integrate with other industrial applications due to its servo mount and 6 mm Shaft.

The Model A36SB industrial applications include X-Y Positioning, Ball Screw Positioning, Printing, Packaging, Mobile Equipment, Material Handling, and Aerospace.

Model A25SB Absolute Shaft Encoder

It is characteristic of serial communication and the IP67 sealing package under a 2.5” industrial multi-turn Absolute Encoder.

The Model A25SB is descriptive of what the Model A36SB offers in addition to its availability in IP67 ratings and having a double-bearing proven design. Moreover, its availability integrates several mounting styles and shaft sizes. The Model A25SB can quickly mock the aftermarket and OEM application designs.

The Model A25SB offers the same industrial applications as the Model A36SB with the exclusion of Printing and inclusion of Metal Foaming & Fabrication.

Model A58SE Absolute Shaft Encoder

It is characteristic of an ethernet capability under a 58 mm Absolute Shaft Encoder.

The multi-turn Model A58SE Absolute Encoder design suits it for a harsh plant and factory environment due to it being EtherCAT or PROFINET-ready. Its application suite requires ethernet-based connectivity and the encoder’s positional information retention property during power loss.

The flexibility of its design makes it easily adaptable to many applications. The Model A58SE rapidly deploys on your network through a direct plug as a minimal provision. Thus the multiple networked devices benefit from the facilitated data exchange platform. The model retains the absolute position information upon power loss and does not need system re-homing to speed up the system’s start-up recovery.

The model is ready for the IIoT (Industrial Internet of Things) and Industry 4.0. The control loop is not affected by how the Model A58SE exchanges data with other applications. The non-reactive property of the model makes it possible for it to work on its objectives from the master or PLC independently. This property makes it possible for related automation sites and networks to receive transferred data through the network gateways, which end up on the cloud for further analysis.

Its industrial applications are Conveying, Filling, Cut-to-Length, Motor Feedback, Printing, Metal Foaming & Fabrication, Converting, Packaging, Mobile Equipment, Material Handling, and Aerospace.

Model 925 Absolute Shaft Encoder

It is characteristic of IP67 sealing and parallel outputs under a 12-to-25 bits robust size.

If the encoder capability requirements demand an absolute positioning output, then this Single Turn

Absolute Encoder is the ideal candidate for such industrial applications. All the industrial applications, with a particular preference to the ones on a high noise presence environment, prefer the Model 925 due to its Opto-ASIC technological innovation and its fully digitalized output. Its design flexibility easily fits it to other applications due to its varied cabling and connector options, and availability of square flange or round servo mounting. The Model 925 adapts to rough environments due to its characteristic optional IP67 seal, heavy-duty bearing, and industrial-grade supported shaft sizes.The Model 925 popular industrial application is X-Y Positioning.

The technology that tags along with the Absolute Shaft Encoder uniquely applies it to the global robotics industry. The 3600 rotation range in regards to its Absolute Position Output, low profile, inertia, & weight, and generous mounting tolerance brings out its superior and flexible qualities in various technological industries. Moreover, the holistic rotor area characterizes the technology with durability. The Absolute Shaft Encoder is, therefore, a pride in the global tech industry due to its fundamental robustness in structure and a high customizability criterion.