Installation of WeDo Python Support

Up

Lego WeDo

Reference

• [Klaig]

Software Dependancies

Some or all of the following are required. Several were install in desperation to solve problems below.

aptitude install python-pip
aptitude install python-dev
aptitude install python-usb
aptitude install python-serial
aptitude install git

Standard install for WeDo Library - Failed

pip install wedo

A possible workaround for the missing CHANGES.rst file.

cd build/wedo/
cat one two three > CHANGES.rst
python setup.py install

Workaround install for WeDo Library that was Used

The CHANGES.rst file is present in this method.

git clone git://github.com/itdaniher/WeDoMore.git
cd WeDoMore/
sudo python setup.py install

Fixing the Missing usb.core

This is the symptom.

sudo python
>>> from wedo import WeDo
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "/usr/local/lib/python2.7/dist-packages/wedo-1.0.0-py2.7.egg/wedo/__init__.py", line 8, in <module>
    import usb.core
ImportError: No module named core

The problem is an old version of pyusb. It should be 1.0 or greater. pyusb fix link I found it at: [1]

unzip pyusb-1.0.0a3.zip
cd pyusb-1.0.0a3/
sudo python setup.py install 
ls /usr/local/lib/python2.7/dist-packages/
    easy-install.pth  pyusb-1.0.0a3.egg-info  usb  wedo-1.0.0-py2.7.egg

Example Run

Python support for the Lego WeDo kit: [Klaig]

sudo python
Python 2.7.3 (default, Jan 13 2013, 11:20:46) 
[GCC 4.6.3] on linux2
Type "help", "copyright", "credits" or "license" for more information.
>>> from wedo import WeDo
>>> wd = WeDo()
>>> wd.motor_a = 100
>>> wd.motor_a = 0
>>> 

From the Klaig site

 To install it:
 pip install wedo

To initialize it if you have a single device:

 >>> from wedo import WeDo
 >>> wd = WeDo()

Activating the first motor full forward:

 >>> wd.motor_a = 100

Activating the second motor half speed/force backward:

 >>> wd.motor_b = -50

Current value of the tilt sensor, you can find the matching constants FLAT, TILT_BACK, TILT_FORWARD, TILT_LEFT, TILT_RIGHT in the wedo package:

 >>> wd.tilt
 3

Current distance value in meters of the distance sensor:

 >>> wd.distance
 0.21