Projects:2015s1-28 Wireless Rotation Detector

Supervisors

• Prof Christophe Fumeaux
• Dr Ali Karami Horestani

Honours students

• 2015: Guowei Deng and Shuopeng Wang, see Wireless Rotation Detector

Project objects

Scope

• Design and construct a portable wireless device which can accurately measure the speed of rotating object.

Specific Aims

• Design and produce a metamaterial absorber with resonate frequency of 2.4GHz.

• Design and fabricate a planar dual-antenna which can transmit and receive signals with limited crosstalk.

• Design a software system which can calculate the rotation speed.

Background & Significance

• Rotation speed measurement devices widely used in industries.

• Current popular rotation speed measurement devices, such as laser tachometer, use visible light.

• Can not use if line of sight blocked.

• Intend to change – use Electromagnetic Wave instead

Fig. 1: Background & significance

Key Requirements

• Metamaterial Absorber shall absorb at least 90% (-10db) power at 2.4GHz when it has same polarization with antenna.

• Dual antennas shall work at 2.4GHz and the crosstalk between 2 antennas shall be less than -40dB.

• Portable system shall be operational up to 50cm from the rotating object.

• Portable system shall accurately measure the rotating object in both low and high speed.

Proposed Approaches

• Method exploited - ‘Divide-And-Conquer’.

• The entire project can be decomposed into several aspects.

• Hardware (design required)

1. Metamaterial Absorber
2. Dual-Antennas

• Software

1. Calculation Algorithm for rotating speed
2. GUI

• Other Components (from market or school)

1. VCO
2. Arduino UNO Board
3. Power Detector

Hardware Design

• Understand the requirements and specifications of the hardware
• Design the hardware in software such as HFSS
• Fabricate the designed hardware
• Measure the prototype and compare the measured results with simulation results
• Redesign if the prototype does not meet requirements

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Software Design

• Software design will start after antenna and absorber design has been finished.
• Software – in C language, based on the Fourier Transform
• Combine software, hardware and other components together and measure the rotating speed.
• Redesign if the measured speed and real speed are not identical.

Entire System

• The entire system is the integration of all several aspects.
• Use ‘Waterfall’ model for the system design.

[File:Waterfall.png|200px|thumb|center|alt text]]