Final Design Report Platform Motion Measurement System ELEC 492 A Senior Design Project, 2005 Between University of San Diego And Trex Enterprises Submitted to: Dr. Lord at USD Prepared by: YAZ Zlatko Filipovic Yoshitaka Yano August 12, 2005 University of San Diego Final Design Report USD August 12, 2005 Platform Motion Measurement System Table of Contents I. Acknowledgments…………...…………………………………………………………4 II. Executive Summary……..…………………………………………………………….5 III. Introduction and Background…...………………………...………………………….6 IV. Project Requirements…………….................................................................................8 V. Methodology of Design Plan……….…..……………..…….………….…..…….…..11 VI. Testing….……………………………………..…..…………………….……...........21 VII. Deliverables and Project Results………...…………...…………..…….…………...24 VIII. Budget………………………………………...……..……………………………..25 IX. Personnel…………………..………………………………………....….……….......28 X. Design Schedule………….…...……………………………….……...…………........29 XI. Reference and Bibliography…………..…………..…………………...…………….31 XII. Summary…………………………………………………………………………....32 Appendices Appendix 1. Simulink Simulations…..………………………….…….33 Appendix 2. VisSim Simulations..........……………………………….34 Appendix 3. Frequency Response and VisSim results……………......36 Appendix 4. Vibration Measurements…………..………………….….38 Appendix 5. PCB Layout and Schematic……………………………..39 Appendix 6. User’s Manual…………………………………………..41 Appendix 7. PSpice Simulations of Hfilter…………………………….46 1 Final Design Report USD August 12, 2005 Platform Motion Measurement System List of Figures and Tables Figure 1. A Moving Platform………………………………………………………….…..6 Figure 2. Micro-Electro-Mechanical-System (MEMS) sensor..…..…….……………….7 Figure 3. Magneto-Hydro-Dynamic (MHD) gyro.………………...………………….…7 Figure 4. Range of frequencies covered by the final product……………………………7 Figure 5. The working principles behind MHD sensor……………………..…………...8 Figure 6. The working principles behind MEMES sensor………………………………8 Figure 7. Vibration Generator System block diagram…………………….……………11 Figure 8. Transfer function of MHD and MEMS...……………………………….……12 Figure 9. Synthesis Method (MathCad)…………..……………………………….……13 Figure 9a. Blended frequency response, MHD filter response, and MEMS frequency response (MathCad)………………………….…...………13 Figure 10. Blending system…………………………….....……………………………14 Figure 11. Low-pass section realization for the first order filter…………………….…15 Figure 12. Hfilter for the X-axis …………….…..……..…………...……………………16 Figure 13. Gfilter and the blending circuitry …………..……..…………...…………..…17 Figure 14. 5V and -2.5V references and zero MEMS offset …………..……..…………17 Figure 15. Experimental vibration measurements…………………………………….....19 Figure 16. Complete system simulation at 10 Hz……………………………………......20 Table 1. Low and high frequency vibration measurements……………………………18 Table 2. Test Plan……………………………………………………………………...21 Table 3. Sponsor Requirements and Accomplishments……………………………….24 Table 4. Budget…………………………………………….…………………………..25 2 Final Design Report USD August 12, 2005 Platform Motion Measurement System Table 5. Member’s task list …..………………………………………………………..28 Table 6. Gantt chart……...…………...………………...………………………………..29 List of Figures for Appendices Appendix1 Fig1. Vibration Generator System-Simulink...…………………………….33 Appendix1 Fig2. Output of Control system…………………………………………….33 Appendix1 Fig3. Code to generate the plot ……………………………………………33 Appendix2 Fig1. Vibration Generator System-VisSim……..………………………….34 Appendix2 Fig2. MEMS output………………………………………………………..34 Appendix2 Fig3. Step input………………………….…………………………………35 Appendix3 Fig1. Y-axis: Simulated blended frequency response …………...……..…....36 Appendix3 Fig2. Z-axis: Simulated blended frequency response.…….………...…..…...36 Appendix3 Fig3. Block diagram for the blended system.…….………...…………….…...37 Appendix4 Fig1. Z-axis vibration measurements…………………………….………….38 Appendix4 Fig2. Y-axis vibration measurements …………………………………...….38 Appendix5 Fig1. PCB Layout of the complete system……………………….………….39 Appendix5 Fig2. XYZ Hfilters…………………………………………………………….39 Appendix5 Fig3. Gfilers and the blending circuitry……………………………………….40 Appendix5 Fig4. MEMS offset and the voltage reference……………………...……….40 Appendix6 Fig1. PCB layout…………………………………………………………….42 Appendix6 Fig2. -2.5V offset with jumpers.…………………………………………….44 Appendix6 Fig3. MEMS directional rotation...………………………………………….45 Appendix7 Fig1. X-axis Frequency response in PSpice……...………………………….46 Appendix7 Fig2. H X-axis filter design……....………………………………………….46 3 Final Design Report USD August 12, 2005 Platform Motion Measurement System I Acknowledgments We would like to thank the people who helped make this project possible. For encouragement, for understanding, and for the use of their equipment and time, our heartfelt thanks go to Trex Enterprises. Mr. Mike Borrello, of Trex Enterprises, made many suggestions on our design which improved the outcome of many tests preformed on the system. With his constant help, the project deadlines were accomplished. The University of San Diego provided the use of lab and the funds for the equipment. We would also like to thank Dr. Kanneman and Dr. Lumori for their help in the design of the vibration generator system, without them the final control system would not have been as accurate as it is. Dr. Pateros introduced us to this project and to the wonderful people at Trex Enterprises and helped us with the PCB (Printed Circuit Board) layout, and we thank him for that. We would like to express particular appreciation to Dr. Susan Lord for reviewing the documents. She made many suggestions and contributed special insights and details to the CDR (Critical Design Review), the FPDR (Final Project Design Report) and the final project binder. We would also like to express our gratitude to the people at Visual Solutions who provided us with the free VisSim software which was used as a primary real-time simulation tool. Sponsor This project was made possible by Trex Enterprises. Trex Enterprises is the leader in optical design and test equipment that support adaptive optics, tracking and laser programs. The design capabilities include Computer Aided Design systems for multi- purpose analyses. “There are extensive facilities to support laser research employing various IR and visible solid-state lasers. Our electronic facilities support research on signal processing, millimeter wave systems, custom digital interfaces and high voltage analog electronics for a variety of applications. Trex Enterprises' engineering facilities include materials research and engineering test labs, electronics design space, as well as mechanical design, electro-optic and electro-acoustic labs” (www.trexenterprises.com). Special thank you to: Ms. Anne Pol, CEO of Trex Enterprises Mr. Eric Woodbridge, Laser Communication Manager Mr. Mike Borello, Senior System Engineer at Trex Enterprises Mr.Peter Darnell, President of Visual Solutions Mr.Rich DiManno, Visual Solutions 4 Final Design Report USD August 12, 2005 Platform Motion Measurement System II Executive Summary The vibrations experienced by the disturbances on any moving platform cause mounted systems to be unstable and unreliable. The vibrations can vary from very low to very high frequencies. It is important to measure the amplitude and frequency of vibrations and to use these data to design more efficient and accurate mounted systems. Using high frequency sensors, such as Magneto-Hydro-Dynamic (MHD) sensors, integrated with low frequency sensors, such as Micro-Electro-Mechanical-System (MEMS) sensors, a large range of vibrations can be measured. The goal of this two semester senior design project at USD was to design and implement a filter that allow these two sensors, MEMS and MHD, to act as one single sensor that can detect both low and high frequency vibrations from about 0.01 Hz to 1000 Hz. Combining these two sensors produces an efficient and accurate measuring tool that allows users to model vibrations over a large range of conditions. To measure the accuracy of the tool, it was necessary to add an additional design task and deliverable. Specifically the design of the vibration generator system (VGS) that generates low frequency vibrations (up to 20 Hz) that was used as a testing tool for the sensors. Using the MEMS’s and MHD’s transfer functions (TF) and the synthesis method (TFMHDxGfilter + TFMEMSxHfilter = TFBLEND) the blended output was obtained. The synthesis method produced a 11th order Hfilter and a unity gain Gfilter. The Hfilter was simplified to a 3rd order filter by canceling the poles that were too close and poles that rd were out of the frequency range. The 3 order Hfilter and a unity gain Gfilter were implemented and built. Implementing these two filters, along with the blending circuitry for MEMS and MHD, on a PCB board a new sensor capable of measuring both low and high frequency vibrations, from about 0.01 Hz to 1000 Hz, was created. Although the sensor was designed to measure frequencies up to 1000 Hz, the actual measurements were only preformed up to 20 Hz due to the vibration generator’s mechanical limits. The new blended sensor preformed with average 90% accuracy. The final product was delivered to Trex Enterprises on August 12, 2005. The deliverables were a simulation and a PCB board. The simulation was hardware in the loop simulation demonstrating blending of the MEMS and MHD sensors and the wide range for vibration detection. The demonstration was executed on a single axis gimbal and the potentiometer rate was used as a true measurement