zurück
back
1. The Job

2. Description of System

     2.1 Control Flow

     2.2 Product Changeover

     2.3 Communication- and Control Components

          2.3.1 EVENTLINK Stream Socket Communicator

          2.3.2 Conveyor Control

          2.3.3 Receipt of PCB-Barcode-Information

2.3.4 Component Validation Option (CatRace Plus)

2.3.5 Feeder Low Display (CatRace Plus)

2.3.6 Traceability on PCB Level (CatRace Plus)
 
     2.4 Hardware Components

3. System Prerequisites

3.1 Software Components

1. The Job

The idea is to prevent PCBs entering the machine, which do not fit to the activated
product program on the machine.
Production reports are generated and sent to the factory MES.

The external controller 'Changeover assistant tRace' (CatRace) takes over this job.

Each single PCB (Printed Circuit Board) is equipped with a barcode label.
CatRace reads the label in order to find if the PCB is appropriate for the production program activated on the assembly machine. Incorrect PCBs will be held back, good ones are released to enter machine for population.

A defined part of the barcode label is qualified to identify the product explicitly.
This information is used by CatRace to determine the production program name by reading a reference table (typically a text file) and to retain/release PCB on the machine entrance conveyor.

Production data with user defined format are send to factory MES

The option Component Validation enhances CatRace to CatRace Plus.
The barcode on the component reel is read before mounting into station by a hand
scanner.
The component barcode is compared to the required component used on this station for
the active product program. CatRace Plus rejects wrong components and disables
production until the correct component was scanned.

2. Description of System

2.1 Control Flow

The controller CatRace runs on a Windows-PC, which is integrated in the production network.
CatRace is directly connected to the Stream Socket Communicator EVENTLINK on the machine through network utilizing TCP/IP.

CatRace receives the PCB barcodes and integrates

- EVENTLINK, communicator module installed on machine,

- the signal controller for switching Conveyor/Maschine SMEMA Signal through a digital
 I/O device,

- the sensor interface for checking PCBs entering the machine.

Each PCB carries a barcode label consisting of the product code and a serial number.

STEPS:

a) CatRace waits for PCB arriving on entrance conveyor

b) A PCB arrives on the entrance conveyor

c) The barcode scanner mounted onto the conveyor reads the barcode label and sends
    and sends it to CatRace through a serial link.

d) The SMEMA signal is switched off by CatRace, the PCB stays on conveyor

e) CatRace compares the currently active product program with the product
  identification of the PCB (product-ID of barcode)

f) Dicision is made: does the PCB fit to the loaded program?
   NO  → CatRace holds conveyor and shows message to manually remove PCB;
             wait for removal, goto a)
   YES → CatRace releases PCB into machine by switching the SMEMA signal on

g) CatRace waits for sensor in machine to see board transferred in

h) CatRace turns Conveyor off

I) Loop back to a)
2.2 Product Changeover

During changeover, executed by the operator, the machine is in STOP-mode.
The SMEMA signal to the input conveyor is switched off for that period of time by the
machine, no PCB can enter.
After changeover is finished and machine has been restarted by the operator,
CatRace requests the new product name and is ready to continue operation.

2.3 Communication- and Control Components

2.3.1 EVENTLINK Stream Socket Communicator

The stream socket communicator EVENTLINK is installed onto the machine.
It informs CatRace about machine events, generates consumption data on
a PCB completed and answers on CatRace's requests.
This communicator replaces a GEM Hostinterface on the machine and a GEM Host
Controller on the control PC. This avoids license costs for GEM.
The benefit of using EVENTLINK in comparison to GEM is the high reactivity
and low protocol overhead data amount. This means a low network load as well.

2.3.2 Conveyor Control

The Universal assembly machine controls the activity of a entrance conveyor by
using the SMEMA protocol.
SMEMA uses two signal ways, each signal way is realized as a two wire electrical potential difference (four wires, two for each signal). .

In order to prevent an uncontrolled PCB transfer, CatRace steps into the
signal handling by internal logic and a digital I/O card plugged into the control PC.

By default the control PC switches on the SMEMA signal handling between machine
through a Normal-Close-Relais of the I/O card, if CatRace is shut off.
Only on active CatRace the signal is permanently interrupted until a good PCB can
enter the machine.
This is to allow production on a system failure.

For signal operation, an adaptor cable is looped into the signal ways, which is
connected to the control PC.

2.3.3 Receipt of PCB-Barcode-Information

The barcode scanner to scan PCB barcodes is mounted on the entrance conveyor.
It sends it information to CatRace through a RS232 serial link.
Typically communication parameters like these are used:
- 8 data bits
- no parity
- 1 stop bit
- 9600 bits/s

The format of the barcode label information is:

The barcode data can also be transferred to CatRace by a socket stream.
This needs to be agreed between the parties.

2.3.4 Component Validation Option (CatRace Plus)

The Component Validation option is to assure the correct components being on the
correct component station.

All component reels must have a barcode label, which holds the component identification.
The component-ID is either directly the name of the component as used inside the
product program or an alias.
If aliases are used, the system needs a component-alias-table (ASCII-File) where
the barcode is referenced to all possible aliases.

The operator scans the station-ID barcode first followed by the component-ID scan.
Now the components are to be mounted at the station.
Another station-ID scan finishes the validation process. On the display of the PC and of the
barcode scanner, the operator is informed about (in-) correctness of component.
If the component is incorrect, the production process is interrupted until the correct
component was seen at the station.

The station-ID barcode starts with the character 'X', the component-ID barcode starts with
the character 'P'.
In addition, the Component reel barcode should also hold barcode information for the initial quantity
of the reel and the lot id.
The initial quantity barcode typically starts with the character 'Q', the lot id with the character 'L'.

The quantity information is used for the Feeder Low calculation, Validation results and Lot information
are merged to the Traceability output.

2.3.5 Feeder Low Display (CatRace Plus)

CatRace Plus calculates the remaing quantities of components per component station in use for the running product program and displays it on the TFT screens.

The quantities are sorted by least values and displayed in a table in different colors.
When a new reel is seen at the station, the value is set to the initial quantity value read.

2.3.6 Traceability on PCB Level (CatRace Plus)

All consumption information, PCB id and Component Validation results for each produced PCB are stored in text files, one for each PCB. A time stamp is stored for each information block.

2.4 Hardware Components

The control hardware for CatRace (Plus) are to be purchased and supplied
directly by the customer.
Please see the following list of components:

- 1 control PC (minimal configuration):
- 4096 MB RAM
- Dual or Quad Core CPU
- 500 GB Hard Disk
- Standard-Graphics Card
- Network Card, 1 Gbit/s
- Keyboard and Mouse
- 2 PCI Slots for PCI-P16R16 and Serial Card
- 2 pieces TFT- Flat Screen
- 1 Signal-Splitter to distribute signal of the Graphics Card to 2 TFT-Monitors
- Operating System MS Windows 7 Home Premium 32 Bit (x86) or XP Professional
- Anti Virus Program

- 1 Parallel IO-Board  PCI-P16R16 (-CR) manufacturer ICP DAS or Spectra (1)
  (alternatively: PCI-P8R8, PEX-P8R8i/PEX-P8R8i (PCI Express slot required))
1 RS232 Serial Card PCI (min. 2 Ports) with drivers for Windows 7 / Windows XP

- 1 Adaptor Cable for Signal Separation SMEMA made under our instruction

- 2 Photo electrical Sensors Type Keyence PZ-42LP with Mounting Bracket
  or
  2 Photo electrical Sensors Type Omron E3S-LS3PW with Mounting Bracket

-  1 stabilized Wall Power Supply 12/24 Volt DC to feed Sensors

- 60 m Data Cable shielded twisted pair min. 2 pairs

- 1 Barcode Reader for PCB Barcode, Communication link RS232 (serial)
     with cable and mounting brackets

For CatRace Plus (incl. Component Validation):

- Handhelt Radio Barcode Scanner Datalogic PowerScan PM8300-DKAR433RK20
(1)

     Kit:

    PowerScan PM8300, 433 MHz, Kit, RS-232 or USB, Laser Scanner, Auto Range,
    Display/16-Key Keypad, Removable Battery
    (Kit inc. Laser Scanner, Base Station, Cable CAB-433, Power Supply,
     Power cord with European plug)

alternatively:

- Symbol LS2208 Serial Laser Scanner Kit

- additional Battery (Accumulator)

- Charging Device for Battery

- Barcode Labels with Component-ID starting with 'P', Code 39; for all
 component reels
 Sample: Component-ID 'RESISTOR' = barcode 'PRESISTOR'

- Barcode Labels with Station-ID starting with 'X', Code 39; for all
 Component Stations. Numbered from 001 to XXX max.-station-number.
 Sample: 1-20 stations = barcode 'X001' - 'X020'

3. System Prerequisites

The following system prerequisites have to be provided by the customer:

- Reference File Produktcode / production program

For analysis of the PCB barcode a reference file is needed.
The file must be reachable through the production network or must reside directly on
the control PC.

   The Reference File(ASCII-Format) has lines of this format:
 
  Produkt-ID is part of the PCB barcode

- Component-Alias-Table for Component Validation

This table is an ASCII-File (Text) which must reside on the Control PC.
It contents of the Component-ID followed by the aliases separated by a SPACE-character.
Each Component-ID assignment is a text line, all line are separated by each other by
CARIAGE-RETURN-characters (RETURN).

3.1 Software Components

If required:

- Barcode read and transfer through socket connection (Stream Socket)
back
zurück
back
zurück