This repo contains all the relevent software to control the Underwater ROV as well as use the camera. It also has instructions to initilize both the a new Raspberry Pi (RPi) and the controling host computer, which should be a Windows 10 machine.
If the initialization process has not been performed for both the host machine and the RPi, please look at the Initilization secion.
Once the host computer and the RPi have been initialized, the next step to running the control software is to run the python script.
Ensure that python has been properly installed on the host computer by running pip list and checking that the gpiozero, pigpio, pygame modules have been installed.
Main file is main_host.py which should be run on the host computer. This script is dependant on two modules and one ini configuration file:
- ROV_Control_Host.py
- camera_server.py
- config.ini
One script file needs to be on the RPi for the camera to work
- camera_client.py
Refer to camera.md for further instructions setting up the camera.
The rest are test scripts for the various components or deprecated scripts kept for testing.
Instructions to prepare the RPi and the host computer are detailed below.
Open the windows power shell by right clicking the start menu. The CMD terminal can also work but the power shell is more powerful and easier to use.
Navigate to the main_host.py script directory using cd. So for example if you downloaded the script file into the documents folder of Windows, navigating to the directory would be: cd c:\users\username\documents
Note: Don't add the script file i.e ROV_Control-host.py to the directory. That tells Windows Power Shell to navigate to that file not the directory
Windows Power Shell should show where you are in the directory.
Run the script using: py main_host.py
Stop the script by either exiting the pygames window or pressing Ctrl+C on the terminal. Please allow the program to run its termination function when shut down has started.
Use the config.ini file to change any necessary settings for the control software such as the RPi host name and the GPIO pins for thrusters.
Values should be self explantory.
- Added camera control
- Added debug option and corresponding config setting.
- Added wrapper script to run both the camera and thruster control programs
- Added multithreaded arming function
- Added user configuration file
Corrected ASCEND and DESCEND control issues: thursters will correctly fire at full when triggers are fully depressed- Reverted: controller corrects deadzone once a random button has been pressed. Right trigger still does not function correctly. Adjust the minmax bounds.
- Corrected thruster control logic
- Remote GPIO connection scheme to its own function
- Implemented new controller API: pygames. Allows Windows host computer to interpret controller input as well as drawing a diagnostic UI.
- Implemented GPIOZero for remote GPIO. Allows the host computer to control the RPis GPIO remotely.
- Improved thruster software logic should iron out dead zone issues.
- Added analog trigger control over thrusters. RT should fire both dorsal thrusters forward to have the ROV accend. LT should cause the craft to decend.
- Fix UI.
- Fix triggers.
- Fix abilty to control the UI color scheme with config.ini values.
- Integrate camera and update readme for camera.
This is to initialize the control system on both the Windows 10 host machine and the RPi. To initilize the camera, refer to the camera.md file.
Need to install pigpio, gpiozero and pygames modules. Also ensure that python is installed on the host computer.
Its also easier to use the Windows CMD to use pip.
To do this when installing python on the windows machine, ensure that set PATH environment variable is checked.
If python is already installed:
- Locate the python.exe on the host machine. Copy the path.
- Go to Control Panel and edit the system environment variables: System -> Advanced Tab -> Environmental Variables.
- In the System Variables or Account Variables, find the PATH Variable. If there is no PATH variable add one.
- When editing the PATH variable add the python.exe directory and another one with \Scripts appended to the directory path.
- Check if pip works in the command line by typing in
pip listorpythonto start the python interpreter.
Install it on the host computer by using the command:
pip install pigpio pygame gpiozero modules
Check all the installed python modules on the machine by using:
pip list
Enable I2C, Remote GPIO in the settings.
Software uses pigpio libary for more accurate pulse width modulation (PWM) to control the ESC and brushless motors. Ensure the pigpio library is installed:
sudo apt-get install pigpio python-pigpio python3-pigpio
Check the version with:
pigpiod -v
The pigpio daemon is a piece of software that needs to be running in the back ground for it to work
To manually start the pigpio daemon use:
sudo pigpiod
or adding this line in the code in the python script:
os.system ("sudo pigpiod")The command to check when the pigpio daemon starts running is:
ps -ef | grep gpio
To have the pigpio daemon start everytime the RPi boots use:
sudo systemctl enable pigpiod
and
sudo systemctl start pigpiod
This has already been enabled on one of the test RPis.
Refer to http://abyz.me.uk/rpi/pigpio/index.html for further instructions.
ESCs are manufactured in china and have spotty documentation. To calibrate the ESCs for forward and reverse, the instructions that came with the ESC say to
- Connect everything to the ESC
- Pulse for the highest frequency
- Power on the thrusters and wait for 2 seconds. The thrusters should beep twice.
- Pulse at the neutral frequency. The thrusters will beep twice.
The arm() function in the python code should take care of all the ESC calibrations for all four thrusters.
Refer to the manufacture's website for specifications: http://www.ztwshop.com/product/shark-brushless-esc-for-rc-boat/ztw-shark-40A-bec-for-rc-boat.html
Functions or drivers that are no longer used but kept for completeness or troubleshooting.
No longer used. The driver is only for interfacing a USB controller with a linux machine. All the controller interpretation is done on the host machine which is most likely a windows machine this no longer works.
To initilize first ensure the xbox controller driver is installed:
sudo apt-get install xboxdrv
To test the driver use:
sudo xboxdrv --detach-kernel-driver
Refer to https://github.com/FRC4564/Xbox for more info on the xbox driver
Static IP addresses seem to give remote and ssh connection errors as well as prevents the RPi from sharing internet when directly connected to the host computer. Its better to just use dynamic IP addressing and connect through normal means.
First establish a static IPv4 address on the host computer via the network configuration on the Control Panel.
Make the IP address something memorable but the default is 192.168.1.1.
Install the DHCP server software:
http://www.dhcpserver.de/cms/download/
DHCP will automatically assign IP addressesses to your PI: default is 192.168.1.2-4
Do not have the IP adresses range collide with the currently set static IP address.
Configure the DHCP server software by giving it the range of IP adresses. Ensure the range should be small considering only one pi is connected at a time.
DHCP will automatically assign IP addressesses to your PI: default is 192.168.1.2-4
Do not have the IP adress range collide with the currently set static IP address
Configure the DHCP server software by giving it the range of IP adresses. Ensure the range of small considering only one pi is connected at a time.
Now use PuTTY SSH or Remote Desktop to connect to the pi directly. Its easier to connect using the default host name: raspberrypi, rather than the IP address. If for whatever reason the raspberry PI's hostname is unknown, then connect to it directly and use the following to get the host name.
sudo hostname