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The purpose of this paper is to highlight the increasing use of rotary or angle encoders and examine two distinct types of non‐contact encoders that employ novel technologies to meet the demands of very different applications.

Firstly, examines the design characteristics of optical angle encoders which are used for precision applications such as rotary format computer‐to‐plate pre‐press machines, machine tool A, B and C axes, and surface mount machines. Then considers magnetic encoder design, including the latest OnAxis™ technology for lower cost applications which require less precision, but are often more physically demanding.

Different rotary motion applications demand different combinations of performance and features to optimise their function – some require accuracy, others repeatability, high‐resolution or low‐cyclic error for velocity loop control, plus cost can also be a key consideration.

There is an increasing need to control rotary motion. An appreciation of the design principles of optical angle and rotary magnetic encoders is necessary to ensure that the correct choice of encoder is made for each application. For an angle encoder system, trade‐offs should be made to determine a realistic specification, and whilst many factors can limit achievable accuracy, techniques are available for reducing any shortfall. For applications where cost constraints and lower accuracy specifications demand a magnetic encoder, robust OnAxis™ sensor technology is gaining acceptance amongst designers, and whilst many of the basic design principles of optical encoders still apply, other specific technical aspects, such as much lower resolution and accuracy must be understood before using these devices. Hidden design costs should also be understood such as installation timings and the environmental suitability of magnets.

Will aid designers of rotary motion systems to make a well‐informed selection of encoder type, based on the detailed needs of their applications, including accuracy and cost budgets.

Intelligent pneumatic actuator (IPA) is a new generation of actuator developed for Research and Development (R&D) purposes in the academic and industrial fields. The purpose of this paper is to show the application of optical encoder and pressure sensor in IPA, to develop a real-time model similar to the existing devices, and to assess the position control performance using a proportional-integrative (PI) controller and a bang-bang controller in real-time.

A micro optical encoder chip is used to detect cylinder rod position by reading constructed laser stripes on a guide rod, whereas a pressure sensor is used to detect the chamber pressure reading. To control the cylinder movements by manipulating pulse-width modulation (PWM) cycles, two unit valves of two ports and two positions were used. A PI controller and a bang-bang controller are used with suitable gain value to drive the valve using PWM to achieve the target actuator position.

The results show the experimental results of the closed-loop position tracking performance of the system using a data acquisition (DAQ) card over MATLAB software.

This paper presents a real-time model used to replace the microcontroller-based system from previous IPA design. The paper proposes two control strategies, PI and bang-bang, to control position using encoder and pressure reading.

To describe new technological approaches and improvements to existing methods of measuring position in automation, sports and general applications.

Starts with interesting applications of established sensor technology in motorsports and aircraft manufacture. Then examines some new position sensors based on novel technology.

Optical techniques including lasers and linear encoding enable high precision position sensing over long distances. Laser scanning systems have some advantages over vision systems for pick and place applications. Differential global positioning system (GPS) and carrier‐wave techniques are giving millimeter accuracy to GPSs.

Highlights the more exciting aspects of position sensing.

Review of the advancements in non-contact laser sensors for much more accurate real time speed as well as length measurements. The paper aims to discuss these issues.

In-depth review of a number of applications of laser sensors.

A wide range of manufacturers in the converting industries have solved measurement problems and realized major improvements in product quality, cost of production and productivity by applying laser measurement as well as reduction in scrap.

Others with the need to make very accurate measurements of speed and length in real time may find that laser sensors may provide the answer.

An expert insight into how to solve real time speed and length measurement problems.