> tree -d-C
.
├── Core
│   ├── Inc
│   ├── Src
│   └── Startup
├── Drivers
│   ├── CMSIS
│   │   ├── Device
│   │   │   └── ST
│   │   │       └── STM32F4xx
│   │   │           └── Include
│   │   └── Include
│   └── STM32F4xx_HAL_Driver
│       ├── Inc
│       │   └── Legacy
│       └── Src
├── icon
├── image
├── lib
│   ├── include
│   │   ├── ak
│   │   └── openssl
│   └── lib
│       ├── engines-1.1
│       └── pkgconfig
├── software
│   ├── mqtt-control
│   ├── sofware-client
│   └── sofware-client-old
└── video

30 directories

Simply, this thesis consists of two topic to produce the control way and feedback way. Raspberry Pi is a client of GUI Controller. Client will subscribe to AGV/<AGV_ID>/control and publish messages to AGV/<AGV_ID>/feedback to send present status. In another way, GUI will publish message to AGV/<AGV_ID>/control to send command and simulate the path tracking.

• GUI message frame: Message has 2 keys which are Method and Payload.
• Method key includes 3 type:

• PROCESS_LIST:

{
    "method": "PROCESS_LIST",
    "payload":{
        "path":"6,6,7,6,6,4,0|0,2",
        "velocity":"high", //high, normal, low
    }
}

• COMMAND:

{
    "method": "COMMAND",
    "payload":"reset_pi" // reset_pi|reset_stm32|excute command...
}

• GUI message frame: Message has 2 keys which are Method and Payload.
• Method key includes 3 type:

• STATUS:

{
    "method": "STATUS",
    "payload":"1,2,2" //"direction (1 for go ahead, 0 for go back),row,column"
}

Besides 1 main thread (MainWindow UI), this GUI application also has 3 sub-threads responsible for MQTT communication and capturing notification.

• UI init with capture task. This task is responsible for capturing messages from all tasks, including MQTT messages from the subscribe task, and pub/sub task statuses. Capture serves as the bridge between the main application and the two lower tasks. The main application sends a signal/command to the capture task, which then forwards the message to the lower tasks.
• Publish task has three cases:
  • PUBLISH_SIG: publishing a message to the broker.
  • SET_TOPIC_SIG: setting the topic to publish.
  • STOP_TASK: killing this task when the disconnect button is clicked.
• Subscribe task has two cases:
  • SUBSCRIBE_SIG: starting to subscribe to the topic and beginning to loop.
  • STOP_TASK: unsubscribing from the topic, then disconnecting from the broker and stopping the loop thread forcefully.

Frames from Camera	Image processing with Optical Flow algorithm