Arcbotics hexapod robot frame with Raspberry Pi Zero and Adafruit 16 channel I2C servo driver

• Hexy Documentation
• Hexy Transcript

Quickstart

The easiest way to get this up and running, on your raspberry pi zero is to do the following on the terminal via ssh.

$ ssh YOUR.RPI.IP.ADDR -l pi 
$ cd /home/pi
$ git clone https://github.com/mithi/hexy.git
$ sudo python setup.py install
$ python -m hexy.demo.demo1
$ python -m hexy.demo.demo2
$ python -m hexy.demo.demo3

Class Hierarchy:

HexapodCore > Hexapod > HexapodPro > DancingHexapod

Sample usage when running python interpreter from anywhere in your system...

>>> from hexy.robot.hexapod import Hexapod
>>> hexy = Hexapod()
>>> hexy.boot_up()
>>> hexy.walk(swing = 25, repetitions = 10)
>>> hexy.walk(swing = -25, repetitions = 10)
>>> hexy.rotate(offset = 40, repetitions = 7)
>>> hexy.rotate(offset = -40, repetitions = 7)
>>> hexy.shut_down()

Also try this...

>>> from hexy.robot.pro import HexapodPro
>>> hexy = HexapodPro()
>>> hexy.lie_flat()
>>> hexy.get_up()
>>> hexy.shake_head()
>>> hexy.wave()
>>> hexy.point()
>>> hexy.type_stuff()
>>> hexy.lie_down()
>>> hexy.off()

And this :)

>>> from hexy.robot.dancing import DancingHexapod
>>> hexy = DancingHexapod()
>>> hexy.boot_up()
>>> hexy.night_fever()
>>> hexy.default()
>>> hexy.dance_tilt()
>>> hexy.squat(angle = 60)
>>> hexy.thriller()
>>> hexy.lie_down()
>>> hexy.curl_up(die = True)

Configuration & Calibration

You may have your servo controllers on different addresses, or your servos plugged into different ports. You will also have to calibrate the min and max range of each of your servos, since these settings vary from servo to servo.

These settings are all stored in the hexy.cfg file. To help with this task, there is a GUI program scripts/detect_controllers.py.

To use this program:

1. First, edit the "controllers" line in hexy.cfg to contain the addresses of your controllers. i2cdetect on the command line can help you learn what to put here. See https://learn.adafruit.com/adafruit-16-channel-servo-driver-with-raspberry-pi/configuring-your-pi-for-i2c for tips on how to do this.
2. Next, run "python scripts/detect_controllers.py" from the top level hexy directory. This will pop up a GUI, so you need to have a VNC session open to your raspberry pi for this to work.
3. Within the gui, go one-by-one for each joint and make sure it is assigned to the correct controller and port. You can use "test min," "test center," "test max" both to make sure you are using the correct controller/port, and also to calibrate the minimum and maximum setting for each servo. Make sure you click "save" after you are done with each joint. This will save the settings back to the hexy.cfg file.