USB Robot Arm Python Controller for Windows 10

This repo is a modified version of python_usb_robot_arm by orionrobots, tailored towards Windows 10.

Requirements

• OS: Windows
• libusb-win32 package
• Python 3.9
  • pyusb library (for USB robot control)
  • flask library (optional, for remote control)

Installation Guide

1. Download the libusb-win32 package.
2. Run the installation wizard. Installing the package in the default folder is acceptable.
3. Plug the robot into your computer via USB.
4. Download and run the most recent version of Zadig.
5. Select the robot device. It may be listed as "Unknown Device #1". Ensure that it is the robot by checking that the USB ID displays 1267 and 0000 (as the Vendor ID and Product ID respectively).
   
6. Choose "libusb-win32" as the driver to be installed.
7. Click "Install Driver". The installation may take a couple of minutes.
8. Install the pyusb library. Installing through pip is suffice: pip install pyusb
9. Run test_connection.py to check that the connection works. The light on the robot should flash five times.

Demos

Click here for demos.

Usage

As a library:

>>> import usb_arm

To initialise the USB connection and the arm itself:

>>> arm = usb_arm.Arm()

The initialization will throw an exception if it fails to find the arm and connect to it. If no errors occur, then all the dependencies are working as expected.

LED

Now lets test it by turning on the LED.

>>> arm.blink()

This will blink the LED five times.

The above three lines have been put together in test_connection.py for you to test.

import usb_arm
arm = usb_arm.Arm()
arm.blink()

The two LED commands are as follows:

• arm.led_on()
• arm.led_off()

The commands take in one optional argument: the duration time in seconds. By default, the duration is one second.

Movement

The following list consists of all single movement commands:

• arm.grippers_open()
• arm.grippers_close()
• arm.wrist_up()
• arm.wrist_down()
• arm.elbow_up()
• arm.elbow_down()
• arm.shoulder_up()
• arm.shoulder_down()
• arm.base_cw()
• arm.base_ccw()

The commands all take in one optional argument: the duration time in seconds. By default, the duration is one second.

Stopping

If you are not using the Flask controller, then you can easily abort the current running movement command(s) by inputting Ctrl+C in the console. Additionally, there is a stop command for the arm if needed:

• arm.stop()

Combining Commands

A callable combination can be created by performing a bit-wise OR operator on two or more commands.

>>> custom_combo = arm.shoulder_up | arm.wrist_down
>>> custom_combo(3)  # perform combined command for 3 seconds

This can also be executed in one line:

>>> (arm.shoulder_up | arm.wrist_down)(3)

Unfortunately, due to the limited amount of current in the system, the arm may not be able to perform two or more movement commands at the same time.

The Flask Controller

The controller can be run on its own by executing the following commands:

>>> from controller import ControllerApp
>>> app = ControllerApp()
>>> app.run(host="0.0.0.0", port=5000)

This will however run the app without connecting to the arm. You can simply connect the arm to the controller by passing the arm as an argument into the ControllerApp initialization. The following script runs the arm with the controller connected.

import usb_arm
from controller import ControllerApp

arm = usb_arm.Arm()
app = ControllerApp(arm)
app.run(host="0.0.0.0", port=5000)

Related Work

• The original reverse engineering of the USB protocol was done by Vadim Zaliva.
• The original code that this repo is based off of.
• PCB scans.