The Best & Donovan Acra-Grade System
Operation and Maintenance Manual
Revision 4

Contents

Overview

System Features
Chain of Events in Processing

CVT System

Hardware Setup
Wiring Schematic
Aloka 500 Setup
Software Setup
Setting Zero Line
Checking Pixel Displacement
Operation Procedure
Consistency Test
Data Export and Analysis
Lean Equation and Initialization File
Data Output to Scale
Communication Parameters
Trouble Shooting
Scan Head Assembly Parts List
Screen Interpretation Picture
Checking Pixel Displacement Picture

Overview

The Best & Donovan Acra-Grade System is designed to evaluate the lean percentage of an animal carcass using non-invasive ultrasound technology at speeds up to 1500 carcasses/hour. The intent in using this technology is to reduce the possibilities of cross-contamination of the carcasses, damage to the carcasses, as well as providing a standardized system for grading the animals. The ergonomically designed scan head facilitates consistent and reliable readings while providing easy-to-use operation. Data can be downloaded directly to a central computer system or electronically transmitted to a downstream scale to be added to the carcass weight record. The system consists of three major components:

1. The ultrasound transducer unit (also known as the Aloka unit)

2. The video display that shows the technician the image being sent by the Aloka unit in real time

3. The computer system that takes the image, interprets the data and computes the lean and fat percentage.

The ultrasound transducer is the unit that sends the actual ultrasonic waves through the carcass and receives the reflected waves. The video screen displays a real time analog ultrasonic image of the carcass to allow for proper positioning of the Aloka unit. The computer takes the image via a video grabber board and digitizes it to allow for processing of the data and analysis of the fat to lean ratio of the animal.

System Features:
•Measures fat depth and lean depth
•Multiple readings assure integrity of information
•Calculates percent lean and total lean index
•Accurate and reliable at high line speeds
•Real-time image analysis and statistical computations
•Automatic electronic transfer of data
•Improves yield management
•Facilitates value based producer pricing
•Optimize processing decisions

This manual covers the setup of the initial configuration of the system and goes through the procedures for optimizing the images and the data collection. It also covers simple trouble-shooting of these setup procedures.

Chain of events in the processing of the pig carcass by the Acra-Grade system.

Figure 1

The system is set up and the zero is set correctly for the scan head currently on the device. This setup will be covered later. The system is now set for its first measurement. The first measurement is an average pig. The Aloka unit transmits ultrasonic pulses from the over 600 crystals in the linear transducer through the pig"s skin and into the fat and muscle and to the bone. Ultrasound sees water as transparent for all intents and purposes, while fat and muscle in the pig"s carcass are reflective. Not including bone and connective tissue, the pig is mostly water, so the system sees most of the pig"s areas as black or empty. Once again the bone and connective tissue are reflective, meaning they produce an image, or a line as it were. This is what gives us our image. The Aloka unit shows us (going from the bottom to the top of figure 1):

1.The rib line
2.The connective tissue for the transition of the muscle layer to the fat layer
3.The connective tissue of the skin to the scan head probe.

It is very important that we know where these lines come from in order to understand the troubleshooting phase of this manual.

The Aloka, after creating the image by bouncing ultrasonic waves off the ribs and connective tissue, sends the image to the video grabber board. The scan head is triggered by the technician. This tells the video grabber board to take the image from the Aloka unit. The image is frozen in time then digitized by the video grabber board (frame grabber) in the computer. The image is digitized into a photo that is 512 pixels wide by 480 pixels tall. The pixels then, because of the precision of the image being created by the Aloka, can be calculated to a definite length. This length is 22.3 pixels per centimeter or .0176" per pixel or .44mm per pixel. After all this machine"s sole purpose is to measure a depth in inches, millimeters or centimeters.

Normally the linear transducer face would probably be taken as zero, but we have added other variables to the equation: mainly the superflab. This moves the initial contact surface further away from the face of the transducer and in turn moves the first line further down the output image. But this really does not matter because we set the zero point line anyway. The thing to remember is that the Acra-Grade system measures between points. The location of zero does not matter, only that it is positioned correctly for the operation of the software. IT MUST BE SET CORRECTLY!!! This is accomplished by referring to the setup procedure.

I will now assume that that procedure has been carried out completely and correctly. The image that is brought into the computer is then processed for signal strength. Almost all faulty readings obtained by the Acra-Grade system have to do with signal quality and gain settings. This results from the computer seeing several lines above the intensity threshold. It then cannot determine correctly which lines are the fat/muscle transition and rib lines. This is not a problem if the technician pays careful attention during the setup procedure.

First the image is scanned from the bottom to the top by the computer. The rib line is detected. This is fairly easy for the computer to interpret.

The most difficult line for the computer to interpret correctly is the fat to muscle transition line. This is the line that makes all of your measurements. If it gets this wrong everything will be wrong. Careful attention has to be paid to this line and its positioning. Gain settings are the key to this line.

The zero line as we have already said is not detected, but is manually assigned a value.

After the image is processed and the lines have been assigned the program calculates the percent lean from all the depths. At this time you get your screen representation. The calculations are performed like this:

•The rib line to the muscle/fat transition line is muscle area;
•The muscle/fat transition line to the manually set zero line is the fat area.

Why you may ask is the zero line set manually instead of automatically. This is simple, pigs have actually three layers of fat and as they get fatter they show themselves one at a time. Most of the pigs you see only have one layer of fat showing and this is fine. But because there are other layers of fat that could possibly be detected and the wrong calculation done the zero line must be a hard coded type of number. So you end up with two lines auto detected and the zero line which you set and never changes. Except in the case of the superflab or other scan head physical parameters.

The importance of setting the zero correctly can not be too greatly emphasized. It is imperative to the correct operation of the system.

Now that you know where the numbers and the lines come from you should be able to trouble-shoot the system.

CVT System Model 501 Hardware Setup

Refer to the following diagram (Wiring Schematic, next page) during setup:

1. Make sure the power is off.

2. Connect the video output (the lower BNC connector) from the Aloka

500V Unit to the video input (the BNC connector labeled IN) of the image grabber board on the computer.

3. Connect the video output (the middle BNC connector labeled OUT) from

the computer to the monitor (the 4" LCD) on the scanning head.

4. Optionally, connect the same video output from the computer to an

external monitor or VCR using a T-shaped connector.

5. Connect the trigger (the BNC connector labeled TRIG) from the computer

to the trigger switch on the scanning head.

6. If the CVT data are sent to an electronic weighing scale, connect from

the CVT computer COM4 the Red wire to the scale Receive Positive (R+), the Black wire to the scale Receive Negative (R-), and the Green and White wires to the Limit Switch.

7. Hang up the scan head using a counterbalance. Correct counterbalance

attachment to maintain "floating" scan head.

8. Keep all electronic units away from water.

9. Power up using a surge protected 4-6 multiple outlets.

10. Ultrasonic settings:

	Setting	Min	Max
Total Gain	75	30	90
Near Gain	-15	-45	00
Far Gain	3.0	0.0	5.0

The settings will be displayed at the bottom of the ultrasonic screen as follows:
3.5MG75N-15F3.0
Where 3.5M = 3.5MHz (Aloka 5049 transducer), G75 = Total Gain 75, N-15 = Near Gain -15, and F3.0 = Far Gain 3.0.

11.The hardware system is ready.

Wiring Schematic

Aloka 500 and Micrus Setup

After hardware setup, turn on the power and check the following:

1. B mode (9) - button lit

2. Magnification (8) - full screen

3. Image direction (9) - button not lit -- ® arrow at top right of monitor (illustration A,1)

4. Focus selection 1 - see upper right screen (illustration A,2) FOCUS:

1 2 3 4 B

To change - press Focus (8) - button lit
Press Menu Selection Switches (3) F1 F2 F3 F4 (illustration A)
Then press Focus (8) - button not lit -- SET

5. Data display of gain settings will show on bottom of monitor.

If off - press Menu (8) - button lit.
use following Menu Selection Switches (3) -

Menu 1
FRM-CO PUNC CONT AGC NEXT ¯ Illustration B

Menu 2
IMG-PO DATE DT-DSP ¯IMG-DIR NEXT Illustration C

Data Display EXIT OFF ON

Then press Menu (8) - button not lit -- SET
Data display of gain settings will show on the lower left of monitor:
3.5MG75N-15F3.0 (illustration D)

6. The following buttons are not used for CVT and should not be activated:

Print	OB CAL
ID	Fetal Weight
Comment	Body Mark Group
New Patient	Joy Pad or Track Ball Function

(If "New Patient" is activated, you must repeat the above steps to reset.)

7. DC power supply for 3" monitor in the scan head should be set on 7.5V and the polarity switch in the up position ( - o+).

See Aloka manual for additional details.

Software Setup

The CVT software will start automatically when you turn the CVT computer on. Its computer screen is similar to the following (your screen may differ a little).

•Pressing the F1 key will momentarily display the status of the menu boxes

(Depths, Areas, Units, Calibration, etc…) on the Aloka image screen at the bottom of the computer monitor.

•Pressing the F2 key will display a list of possible probe

selections. To get out of this screen press the Esc key. This function should not be used once the Acra-Grade System is set up. Changing this option will cause incorrect measurements.

•Pressing the F3 key selects various file-saving options for the images.

This option is not used during normal operation of the system.

•Pressing the F4 key selects different units in which to display the data on the image.

(px for pixels, mm for millimeters, cm for centimeters and in for inches)

•Pressing the F5 key selects the triggering options.

The choices are AutoD On1/On2/Off. AutoD On1 means automatic depth measurements with 1 trigger. AutoD On2 for automatic depth measurements with 2 triggers. AutoD Off will turn the automatic depth measurements off. The computer will beep if AutoD has not been purchased or if the computer does not have enough memory.

•Pressing the F6 key allows you to select the transducer standoff guide row location.

This function should not be used once the machine has been set up. Changing this option will cause incorrect measurements.

•Pressing the F7 key toggles the AutoIDOn/AutoIDOff function. This function is not used.

•Pressing the F8 key toggles the AutoWtOn/AutoWtOff function. This function is not used.

•Pressing the F9 key toggles the QualityOn/QualityOff function. This function is not used.

•Holding the Ctrl key and pressing the F10 key at the

same time toggles between memory allocation and de-allocation for the original image. It beeps if there is not enough memory available.

•To exit from the program to the command prompt, press Esc twice

or Ctrl C. You may see the following message displayed on your computer screen after you exit:

+---------------------------------- -----Welcome to CVT System---------------------------------------+

Carcass Value Technology System, Animal Ultrasound Services Inc., Ithaca, NY   

----------------------------------------------- --------------------------------------------------- --------------

 To start the CVT software, type in the following at the command prompt and      

 then press Enter(CVT runs itself when power is on. Press Esc twice to exit):        

 

       CVT ¦

 

 If C:\AUSK\EXE\CVT.BAT exists and you do not want to change or reset any of

 the following settings, CVT is the only name you need to remember and use.

 

    Batch file name to create (No file path or extension) [CVT]

 Data file name (e.g. mypen1 Date Time DateHour; N= NoSave) []

 Unit of measurement (e.g. in cm mm px)

 Standoff row (0=Reset Other= new value)

 Number of triggers (1=automatic release 2= manual release)

 Data export to (0=No 1=COM1 2=COM2 3=COM3 4=COM4 5= Printer) [4]

 Digital images (0= No Load/Save 1= Load 2= Save)

 

 

 To create or change settings in CVT, type in the following at the prompt

 and then press Enter. Follow the instruction on the computer screen.

 

 AUSKCVT

+-----------------Technical Support Phone/Fax: 607-257-7649-------------------+

c:\ausk\txt\cvt>