Remote Controlled Pi

With this library you can video stream from your Raspberry Pi with a Pi Camera. The added feature is a on-screen joystick that works on touch-enabled devices and on regular computers. The measured movement of the joystick is then relayed back to your Raspberry Pi, where you can then do anything with it - for instance, driving a robot.

Here's an example project done with a GoPiGo3 robot.

How to use it

In order to process the joystick's movement, you have to take a look at robot_commands function that resides in flask_server.py script. In this function, you get new updates of the joystick every 250 ms. In this function, there are a couple of variables that were already assigned queried values. Here's what it means for each of it:

• state: It's set to move when the joystick is moved away from the center and stop, when the joystick is released (and destroyed).
• angle_degrees: The orientation of the joystick's small circle relative to the big circle. It's anti-clockwise and it starts at 0 degrees at the right (where the joystick is pulled to the right). It's measured in degrees and the values go from 0 up to 360.
• angle_dir: It tells the general orientation of the joystick. It can be up/down/left/right.
• joystick_pull_force: It tells how much the user is pulling the joystick from its center. The values start at 0 and don't have an upper limit. The upper limit is determined by the screen size.
• determined_speed: Is computed from joystick_pull_force. The advantage is that this speed is relative to a given range (a max and a min constant).

Since I've added a GIF showcasing the GoPiGo3 I also added code for the GoPiGo3 inside the server, so if you want to test it on your robot, just uncomment anything related to the GoPiGo3 (imports, function calls, exceptions and such) and add yours instead.

Setting Up

Install the Pi Camera dependencies and Flask by running the install.sh script:

sudo pip3 install -r requirements.txt

If you want to run the script just as it is, you also need to install the gopigo3 library from GoPiGo3 Repo. Otherwise replace everything on the GoPiGo3 in the script with the function calls needed for your own robot.

If you have followed the above instructions, then by now, you should now have everything set up.

Running it

Start the server by typing the following command:

python3 remote_robot.py

It's going to take a couple of seconds for the server to fire up. A port and address will be shown in there. By default, the port is set to 5000. Take your Raspberry Pi interface's IP address and port and use it on a mobile device or laptop in order to reach the web page. The webpage's address will have the following pattern:

http://[raspberrypi-ip-address]:[port]

Also, make sure you have your mobile device / laptop on the same network as your Raspberry Pi. Otherwise, you won't be able to access it.

Example Project

This is a project done with this library and with a GoPiGo3. Check it out on YouTube.