1 Quiz Preparation l Have Quiz sheet ready

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Quiz Preparation l Have Quiz sheet ready. Title = QUIZ 6 Lab Day/Time Section » Name (L, F, MI), Number » Today’s date 9/25/12, Mon. 1: 00 8 Mon. 3: 00 9 » Lab day , time Tue. 2: 00 36 » section number Lab Day/Time Section Number Monday, 1: 00 8 Monday, 3: 00 9 Wed. , 1: 00 10 Wed, 3: 00 11 Friday, 1: 00 Wed. 1: 00 12 10 Wed. 3: 00 11 Thu. 2: 00 35 Fri. 12 1: 00 2

Announcements l First professional development memo (PDM) due in lecture in 2 weeks – Oct. 9. l This week’s lab (Lab 6) has a pre-lab assignment. We will work it in class today. l Q 1 – What date is PDM 1 due? 3

Equipment Checkout This week you will get your TX, RX, and MC l Checked out to Team Leader. Need Banner ID and phone #. l You can leave these in lab if you prefer. l 4

Motors l Everything you ever wanted to know about Lego motors – l http: //www. philohome. com/motors/motorcomp. htm l Some Diff Eq thrown in: http: //nxt-unroller. blogspot. com/2011/01/motor-controllerwith-feed-forward-for. html l 5

Lego Car Project l Wirelessly driven Lego car l Left and right channels/motors for steering l Goal is to navigate and finish course as quickly as possible 6

7 Required Gates Push block across finish line or incur a +30 sec. penalty Optional Gates (+5 sec. penalty if missed) BLOCK START/ FINISH

Lego Car Overview R 1, R 2 PPM Receiver PWM Motor Control Board PWM 8

Pulse Width Modulation Vo Vo l l l Vo determines maximum motor speed. Larger Vo makes car go faster, but there are penalties for Vo above 10 V. Set Vo with a voltage regulator on the motor control board. 9

Motor Control Board l l Voltage regulator outputs a constant voltage Vo as long as Vin > Vo + 1. 5 V. Set Vo by choosing resistors R 1 and R 2. 10

l LM 338 voltage regulator data sheet 11

Voltage Regulator l l l Vref and Iadj are given. Choose R 1 and R 2 to set Vo. In lab, R 1 will be given and you will vary R 2. » In the competition, you can choose both R 1 and R 2 » Only certain values of resistors are available 12

Quiz Pause…. l Q 2 – What determines the voltage regulator output? » (a) Resistor values » (b) Position of an adjustment knob » (c) Transmitter joystick Write the letter of your answer and also the complete answer. 13

Penalties l Penalties are a way to introduce “cost” into the design and cause the team to make tradeoff decisions. » Incurring a penalty should not be considered unethical or “wrong” in any sense. l l l 5 second penalty for missing a gate 30 second penalty if the block is not pushed across the finish line Penalty of 1 second for each 0. 5 V over 10 V in voltage regulator output (Vo) » » Vo ≤ 10. 0 V = no penalty 10. 0 V < Vo ≤ 10. 5 V = 1 second penalty 10. 5 V < Vo ≤ 11. 0 V = 2 second penalty etc. 14

l Q 3 – What is the purpose of penalties in competition scoring for ENGR 1110? » (a) Punish the unethical » (b) Introduce cost and force tradeoffs Write the letter of your answer and also the complete answer. 15

Lego Car Design l Output voltage » Higher output voltage increases speed » Penalties apply above 10 V l Power supply (batteries) » One 9 V battery (light, but less than 10 V) » Two 9 V batteries (≥ 10 V, but heavy) » Watch batteries (very light, but drain quickly) l Wheel size and gears » Torque vs. speed tradeoff l Drive strategy » Front wheel vs. rear wheel drive l Course path » Passing through all gates vs. missing gates » Pushing block vs. not pushing block l Body » Light vs. heavy 16

Tables/ Spreadsheets/Graphs 17

Tables vs. Graphs l Tables are an effective method for organizing and presenting design data. l Tables are good for recording and calculating precise numerical results. l Tables can be created conveniently in MS Word® or Excel®. 18

Tables vs. Graphs l Graphs are effective for showing trends in the data l Graphs are effective for visually interpolating “in between” values 19

Tables vs. Graphs l Q 4 – Trends in data are best shown through » (a) Graphs » (b) Tables l Q 5 – Precise numerical values are best shown in » (a) Graphs » (b) Tables Write the letter of your answer and also the complete answer. 20

Tables vs. Graphs 21

Tables vs. Graphs 22

American Wire Gauge l Resistance per unit length increases with gauge 23

Tables vs. Graphs 24

Tables 25

Table Formatting l Use the fewest lines necessary to guide the eye for a cleaner look. 26

More lines than needed… 27

Cleaner layout 28

Table in MS Word 29

Table in MS Word -- Result 30

MS Word Tables in MS Word are STATIC l Potential problem: l » Values in the table are related by a formula » A value in the formula changes l In MS Word, all the affected values must be recalculated and re-entered manually. 31

Table in MS Excel is a table! 32

Tables in Excel inherently organizes material into tables. l Tables can actually calculate entries automatically. l Numbers can easily be formatted to reflect the proper type of data and precision. l 33

Excel Table Example l Ideal weight for a 5’ 0” male » 110 lbs. l For every inch above 60” (5’ 0”) » Ideal weight increases by 5 lbs. » Ideal weight = 110+(height-60)*5 l Create a table of ideal weights for heights from 60” to 78” 34

Excel Table Example Formulas l Absolute references l Sizing of rows and columns l 35

Another Excel Example l Car payment » Loan Amount » Interest Rate » 3 year (36 month) duration l Compute » Payment » Amortization schedule 36

Pie Chart Example l New-hire engineer assignments 37

Last Slide Q 6 – When and where is your skit due? Ans: Tues. Oct. 16 by noon to Canvas 38