BME3508_Fall2021_test1-solution

.pdf

School

University of Florida *

*We aren’t endorsed by this school

Course

3508

Subject

Mechanical Engineering

Date

Dec 6, 2023

Type

pdf

Pages

Uploaded by AgentHamster3559

BME3508 Biomedic a l Signals and Systems Fall 2021 September 17 th BME3508: Biosignals and Systems Test #1 Name: ___________________________________ UFID: ________________________ Q1 [30] Q2[30] Q3 [30] Q4 [10] Total [100] Instructions: 1. Write your name ON EVERY PAGE. 2. Number the pages. 3. Write your answers on the front pages only. DO NOT write on the back of any page. 4. Show all your work. 5. Make sure you scan every page. 6. Sign the academic honesty pledge. Academic Honesty: All students admitted to the University of Florida have signed a statement of academic honesty committing themselves to be honest in all academic work and understanding that failure to comply with this commitment will result in disciplinary action. This statement is a reminder to uphold your obligation as a UF student and to be honest in all work submitted and exams taken in this course and all others. I affirm that I have acted in accordance with the UF Academic Honesty Guidelines. Signature ____________________________________________

Biosignals & Systems Name:______________________________ BME3508-Fall 2021 Test #1 Page 2 of 7 Question 1: [30pts] You have joined the Engineering Research & Development team at Medtronic. The team is working on a revision of their patent, “ Programmable waveform pulses for an implantable medical device ”, aiming to change the old square wave-like stimulation waveform. The goal is to replace the sharp rise of the first pulse of the stimulation waveform (“hard - start”) , with a smoothly rising pulse (“soft - start” ), described by x 1 (t). The second pulse of the stimulation waveform is described by x 2 (t). It is essential for the overall stimulation waveform to be charge-balanced, which means that both pulses, first and second must have the same size (strength). Figure Q1.A Left : x 1 (t) depicts the “ soft start” puls e (first pulse) of the stimulation waveform. Right: x 2 (t) depicts the second pulse, of the stimulation waveform. A) [15pts] Choose a proper measure of size (Energy or Power) and calculate the size of each signal. What is the amplitude ratio ( ࠵? ࠵? ) for which ࠵? ࠵? (࠵?) and ࠵? ࠵? (࠵?) would be of equal size. B) [10pts] The team needs to mathematically describe the overall stimulation waveform ࠵?(࠵?) , where ࠵?(࠵?) = ࠵? ࠵? (࠵?) + ࠵? ࠵? (࠵?) . Sketch ࠵?(࠵?) and describe it mathematically using common signals and time domain operations. ࠵?(࠵?) = √࠵? √࠵? Xzlt )={-MB, ⾨ tE8 0,01W ✗ if )={ ☒ hostel ☒ , lets } 0,01W - binalsau aperiodic Ifinite • • Exifexttiidt µ× i÷÷÷ " " ¥ A=s ☐ =/ Bdt =§Atidt+ / Adt = , µ ; | € A # 1.313 =A ¥ /dtÉt| ? =A+2A=IA Ma - - B- rant cult ) - net -113 + Frutti ) - ult -33 ] - cult -5 ) - ult - 8) ]

Biosignals & Systems Name:______________________________ BME3508-Fall 2021 Test #1 Page 3 of 7 Question 1: [30pts] continued C) [2.5pts] The lead engineer assumed arbitrary values for the amplitude A and used MALTAB to plot the overall stimulation waveform, ࠵?(࠵?) , depicted in Figure Q1.C. The lead engineer referrs to x(t) as a zero-mean signal. Do you agree/disagree? Why? [1-2 sentences] Answer: D) [2.5pts] How would you change your ࠵?(࠵?) expression in part B) to match the waveform if part C? ࠵?(࠵?) = Figure Q1. C I disagree . The signal is a non - Zero mean signal as the waveform is centered around ~ 1 and not Zero . It seems that He waveform is shifted up by 1 . ✗ fixed ( t ) = ✗ ( t ) ¥ ⊥ me value by whid the entire waveform was shifted up .

Your preview ends here

Eager to read complete document? Join bartleby learn and gain access to the full version