Project: High Accuracy Length and Angle Measuring System with Absolute Position Output

For any controlled process where the relative position in length or angle between moveable parts has to be controlled, there is a need for position feedback devices. _x000D__x000D_Generally, such a positioning system as part of an automatic equipment consists of a mechanical part with a guiding element for the moveable parts, a controller, an actuator (electrical motor; hydraulic or pneumatic) and a position feed back device. Besides the position information, the measuring system can deliver in an electrical servo driven axes the commutation angle for the motor coils._x000D__x000D_The measuring systems (further “encoder”) can work in the following two modes:_x000D__x000D_ - incremental mode – the encoder supplies for each relative displacement a proportional number of increments which are counted in the controller to determine the actual position considering an “offset” to a “homing”, reference point. _x000D__x000D_- Absolute mode – the encoder supplies for each moment of time and displacement a unique position value. _x000D__x000D_The advantages of the absolute mode are obviously:_x000D__x000D_- increased equipment and operator safety: encoder pulse malfunction doesn’t lead automatically in a position “loose” which can result worst case in an axes crash or injury of the operator. _x000D__x000D_- higher productivity: no more homing procedure necessary _x000D__x000D_- transfer of position data to the controller via serial interfaces with higher noise immunity and less number of wires. _x000D__x000D_- decentralisation of the drive systems by enhancing the encoder functionality, data transfer via state-of-the-art bus systems _x000D__x000D_- commutation inside the encoder, no additional Hall sensor or supplementary commutation procedure necessary anymore_x000D__x000D_The increased performance of today's digital data bus transfer results in strong demands of the market for a general purpose absolute encoder system, e.g. many users of position measuring and control systems are looking for "ideal" absolute encoders for a long time. However, even today there is no general solution available on the market. There are only some limited market segments where absolute encoders are used, for instance resolver, rotary encapsulated encoders or high-end equipment for special applications (restricted equipments (e.g. optical devices)._x000D__x000D_On the other side, the state of the art in sensor and semiconductor manufacturing technologies allows now in combination with AMO's inductive AMOSIN® principle the development of such an absolute angle and position measuring system with high accuracy and dynamics. This is the CO objective of the proposed project. The system will be suitable for a large range of applications including the use in harsh environments._x000D__x000D__x000D_The goal of the actual project is the development of an absolut measuring system for legth and angle with high accuracy and dynamics, for a large field of applications, suited for harsh environment, based on the inductive AMOSIN technology._x000D_

Acronym ABSYS (Reference Number: 4699)
Duration 02/03/2009 - 28/02/2013
Project Topic A fully original displacement system used as feed back for absolute positioning in automated processes has to be researched and developed based on the patented inductive operation principle of the company AMO GmbH for incremental measuring systems for length and angle in submicron range.
Project Results
(after finalisation)
The CO objective of the project was the development of a completly new family of High Accuracy Measuring Systems for Length and Angle with absolute operation funtionality. The company AMO GmbH owns the pure inductive measuring principal of operation AMOSIN (several granted patents and brand) which was applied till now only in Incremental length and angle measuring systems, as CO field of activity._x000D_ Based on this principal of operation has been developed in the frame of this project an extended scanning procedure for the sensing and signal evaluation of an absolute coded grating. This Procedure and device concept Development has been applied in the realisation of the CO components of the measuring system:_x000D__x000D_ 1) Scale : Development of a mathematical model for a parametric generation of random code strings. These strings have been implemented over a photolithographic technologie on the scale carrier. The engraved grating pattern defines for each position an unic code that can be scanned from the measuring head and transformed in lenght or angle information with high resolution of till to 0,1µm._x000D__x000D_2) Inductive absolute sensor: has been developed a planar coil structure combining the incremental and absolute functionality. This novel configuration has been filed as PCT Patent and already granted in several countries. _x000D__x000D_3) Evaluating electronics: The complex evaluating electronic circuit containing two different ASIC's (A6 and POSI6) governed by a FPGA. The development of the ASIC's and the implementation of their analog part has been realised in cooperation with the project P, the company GEMAC._x000D__x000D_Based on this developments there were already designed and applied on the market Linear and Rotary Measuring Systems (see AMO product brochures LMIA and WMIA under The feedback of our customers is extremly positiv and we have high expectations for the future marketing of the devices._x000D__x000D_
Network Eurostars
Call Eurostars Cut-Off 2

Project partner

Number Name Role Country
2 GEMAC - Gesellschaft für Mikroelektronikanwendung Chemnitz mbH Partner Germany
2 Automatisierung Messtechnik Optik GmbH Coordinator Austria