HIC: High-resolution inductive coil-on-chip position sensor for linear motors

• Forschungsstelle: EU FRP
• Projektnummer: 00.0006-1
• Projekttitel Englisch: HIC: High-resolution inductive coil-on-chip position sensor for linear motors

Schlüsselwörter (Englisch)

Coil-on-chip; inductive sensor; POSIC

Alternative Projektnummern (Englisch)

EU project number: IST-1999-20445

Forschungsprogramme (Englisch)

EU-programme: 5. Frame Research Programme - 1.2.4 Essential technologies and infrastructures

Kurzbeschreibung (Englisch)

See abstract

Partner und Internationale Organisationen (Englisch)

Coordinator: Kymata Netherlands BV (NL)

Abstract (Englisch)

HIC is a European Project with the goal to develop a new generation of piezoelectric linear motors with an integrated position sensor system for high resolution feedback.
Nanomotion is a leading developer and manufacturer of piezoelectric linear motors. For a number of applications (e.g. high-resolution scanning), the currently available linear sensors are too expensive (around € 700.00), have an insufficient resolution (5 - 10 µm) or are too big to be integrated in Nanomotion's linear motor system (height and/or width exceeding 15 mm).
POSIC's inductive sensor technology has the potential to combine a good resolution with small dimensions and a moderate product cost. These facts led to the definition of the HIC project, which started early 2001 with 3 main technical-commercial requirements :
- Resolution 1 µm
- Dimensions 15 x 15 x 50 mm3
- Price at 10'000 units € 100.00
During the project, the following items were developed :
- Linear scale optimized for maximum signal to noise ratio. By etching rectangular slits of 1.5 mm at a period of 2.5 mm in a N42 Nickel-Iron target strip on top of an aluminum carrier the maximum SNR was obtained, which was necessary in order to achieve the best resolution.
- A dual-sensor configuration was developed that improves the SNR and at the same time allows the identification of both the left and the right end of the linear scale. This avoids the use of additional sensors, which are typically necessary in other types of linear sensors and add to the system cost.
- A complete interpolation algorithm was developed and tested in MatLab. This algorithm takes the sensor signals (Sine and Cosine), calculates the angle (Arctangent of Sine/Cosine), and calculates the linear position from the calculated angle.
- The algorithm developed and tested in Matlab was translated into VHDL and then implemented in an FPGA.
- The complete system consisting of 2 sensors, analog circuitry, two 14-bit AD converters, FPGA and associated memory was integrated on 3 PCBs that fit (including internal connections) into an aluminum housing that measures 15 x 15 x 50 mm3.
The detailed technical reports on the project clearly show that at the end of the project the resolution of 1 µm was measured and that the dimensions of the sensor were as specified at the project start. The cost analysis report shows that the sensor fabrication cost is below € 100.00 at quantities above 10'000 units.
Conclusion : the technical/commercial objectives of the project have been achieved
The project partners POSIC and Nanomotion have expressed their intention to continue their collaboration in the form of the industrialization of the developed product and the subsequent market introduction.

Datenbankreferenzen (Englisch)

Swiss Database: Euro-DB of the
State Secretariat for Education and Research
Hallwylstrasse 4
CH-3003 Berne, Switzerland
Tel. [phone]
Swiss Project-Number: 00.0006-1