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Extend QT Gui on TXT controller

DRAFT - DO NOT IMPLEMENT

⚠ This specification is due to change.

Abstract

Extend QT Gui on TXT controller to toggle mode (demo / normal) and enter mhu number. Potential by-pass implementation for reading mhu number from QR-codes (camera).

This features includes the following items:

  • implement a toggle push bar (or: toggle-slider) to switch from normal operation to db-demo mode
  • implement a number block with display to enter an mhunumber (int)
  • implement a START, LOAD and STOP button.
  • implement a HALT button (optional).

Rationale

The following discus the background of the two requirements:

  • The 'mhu' (material handling unit) is used to identify a work piece (these funny white, red and blue colored wooden cylinders that represent a transport carrier with a material on top). When an sfcu (shop floor control unit) should be executed the storage will issue a material from stock and load it on a transport carrier. To let a station know what to do with this object (or: whether it is expected to be there at all) this object's 'mhu' has to be connected to the sfcu (see feature #75) As long as the camera integration is new and perhaps subject to changes a simple method to communicate the mhu to the station is desirable and would allow the station to lookup the paired sfcu for it. This could be achieved by enabling users to manually input the mhunumber to the station TXT display.

  • The station can be run in two main modes: normal or demo. In demo-mode, a fresh standard database is recreated whenever the runstn.py module is restarted. In nomal-mode the configured database will be re-used in state is was left after last exit of runstn.py

  • In "emergency" cases the station's operation can be halted immediately by issuing a haltevent. This could implmented as a gui button or as a hardware switch, using the TXT's interrupt capabilities (to be defines)

Specification

These requirements are related to app.txt.station_type.pkg.startup.py

Wireframe specification

This specification holds for both use case described below. Items are marked by embraced number, e.g. (5).

grafik

Use Case: Start a Station's Operation

  • Description: a user wants to start an operation with a work piece.

  • Base Sequence:

    1. The user starts the machine controller on TXT display (1).
    2. The TXT offers the following controls:
      1. A toggle Demo-button (2) to switch between 'normal' and 'demo' (default) mode.
      2. A Start button (3).
      3. A Stop button (7)
    3. The user presses the Start button.
    4. The TXT initializes the station to status ready and displays a number block (4) to enter am mhunumber.
    5. The user enters the 'mhu' number printed on a work piece press the Load (5) button and puts the work piece to the station's loading gate ("inlet").
    6. The TXT looks up the database and retrieves the sfcu for this work piece and starts operation.

  • Branch Sequences:

    • 3A [Station should run in normalmode]
      • 3A.1 The user toggles the Demo-button to normal or off
      • 3A.2 Use case proceeds with 3.
    • 4A [Emergency]
      • 4A.1 The user presses the HALTbutton or device.
      • 4A.2 The TXT controller issues a 'halt' event to the state machine and stops all operations (immediately).
      • 4A.3 The use ends.

Use Case: Stop a Station

  • Description: a user wants stop a station gracefully.
  • Pre-Condition: the station is in state STANDBY, HALTED or STOPPED
  • Base Sequence:
    1. The user presses the STOP button.
    2. The TXT issues a stop event and the station will transition to STOPPEDstate.
    3. The display will be refreshed to Sequence step 2 of use case Start a Station's Operation
  • Note: the TXT program is still running but the station will not react on any work pieces put at the loading gate (inlet).
Edited by Ralf Banning