National Instruments NI myRIO, Essentials Manual

Page: 64 / 163

58 CHAPTER 8. COIN COUNTER
Functional Requirements: The Coin Counter will:
1. Accept an image of an arbitrary number of coins of at least four classes
(denominations) of coins,
2. Accommodate up to 15 coins in the field of view (FOV),
3. Report each coin’s denomination as a text label superimposed over the
coin,
4. Display the number of coins and total value both on the front panel as
well as on an external LCD display,
5. Recalculate the real-world units scaling factors based on a coin of known
diameter selected by a user-defined ROI when calibrate is clicked,
6. Display the analyzed image when show analyzed is pressed, otherwise
display the webcam image,
7. Display the measured diameter of the coin used for calibration, and
8. Display the calibration scale factor.
Figure 8.1 on the previous page shows the front-panel of the Coin Counter
application. Note the use of distinct foreground and background colors for the
overlay text labels, as well as the user-defined ROI around a coin of known
diameter. Figure 8.2 on the facing page shows the image produced by the Vision
Assistant script.
Required Resources:
1. NI LabVIEW and NI Vision Assistant
2. NI myRIO with power supply and USB cable
3. USB webcam and tabletop camera copy stand
4. Black velvet paper background
5. LCD display (Digilent PmodCLS)
6. Coins – ten samples each of at least four coin classes (denominations)
Deliverables:
1. Lab report or notebook formatted according to instructor’s requirements;
include front-panel screen shots to demonstrate that your application
meets functional specifications