1. ANC-PRO (#22) A CTIVE N OISE C ONTROL IN H IGH S TRESS E NVIRONMENTS Greg White Tyler Mose Logan Jennyc Mike Krawczyk Jon Samuelson Advisor: Norm Bartley

2. T HE P ROBLEM Machinery is used extensively in today's society Long term exposer can lead to hearing problems Many environments contain noise pollution Image obtained from http://www.globaltvedmonton.com/Westjet+plane+ makes+emergency+landing/2396494/story.html Image obtained from http://www.automation-drive.com/cnc- machine-shop Image obtained from http://tracyroberts.ca/?p=344

3. T RADITIONAL SILENCERS Can be expensive to build, maintain and operate Susceptible to high levels of heat, compressed gases and acid Image Provided Courtesy of Noise Solutions Inc. Image provided courtesy of Noise Solutions Inc. Image obtained from http://www.sr20-forum.com/general-sr20/1821-quest-quiet-muffler-13.html

4. T HE SOLUTION Active Noise Control System The idea behind ANC is the application of a 180 o delayed sine wave to an incident wave. The out of phase waves undergo destructive interference, and are effectively cancelled out. Obtained from: Representing a Radio Wave With a Sinusoid by Peter Wittenberg http://radarproblems.com/chapters/ch05.dir/ch05pr.dir/c05p1.dir/c05p1.htm

5. Mike, add your shit

6. H ARDWARE C HALLENGES Fitting an end cap to the propagation tube is deceptively difficult Special microphone required to pick up low frequency tones Most microphones have too small diaphragm Hardware versions of pink noise generator and BPF require amplification

7. H ARDWARE C HALLENGES (2) Microphone input on MacBook does not work with unamplified source USB sound card only supports mono input New assumption that the frequency would be captured using an alternate method e.g. Optical encoder on engine fly wheel

8. S OFTWARE C HALLENGES NONE, because I AM AWESOME !!!

9. S OFTWARE C HALLENGES (2) Just kidding - about the NONE Setting up the FFT algorithm to run as fast as possible Clicking in cancellation signal due to constant phase shift Reducing phase shift jumps as the incident power is reduced

10. S OFTWARE C HALLENGES (3) Large phase discontinuity between maximum and minimum delay points May never find peak cancellation phase if both sides of discontinuity are on the downslope

12. C ONCLUSION Image courtesy of http://ragebot.com/p=5153

13. T ECHNICAL ASPECTS Working Prototype Hit all target specs except one Met all deadlines thus far Maintained high standard of quality

14. C ONCLUSION (2) Academic advisor Demonstrated on Thursday March 31 st Norm Bartley satisfied with prototype Industry advisor Andrew Faszer was too busy to come for a demonstration Andrew satisfied with prototype Group Everyone performed according to their roles

15. N EXT S TEPS Capstone Design Fair Model is ready Requested power supply and extra space Final Report All sections have been assigned Working on initial draft Faulty Marks Team Evaluation

16. F UTURE W ORK This project successfully demonstrates the proof of concept Next step would be to ramp it up to a real world system Design and build control system housing structure Design and build chip for control program Use electronics that are resilient to stresses found in an engine Test noise suppression Vs. actual engine sounds