Skip to main content

random things during the week

had one more Arduino Pro Mini ordered,

soldered the pieces in once I received it. 

also did work on one sizable project that looked something like:




somewhat a long story,

but the result was - back to square one, will have to attempt again. 

Comments

Popular posts from this blog

setting up pwm

There's always an obstacle.. I implemented the pwm module as described in the link in the previous post, but oddly enough, it didn't work. The error I received: AttributeError: 'module' object has no attribute 'PWM' After some time scratching my head, I came to the realization that somehow my python was running an older version of the RPi.GPIO library, as PWM control was a pretty recent addition to the library.  And indeed it was.  Not really sure what's happening in detail, but it seems that there are two different... entities? that manage libraries for Python. One is through the usual "apt-get" command and the other is "pip." It appears that Python looks at "pip" first, and it currently linked RPi.GPIO to a really old version of the library.  Uninstalling that older version ("pip uninstall RPi.GPIO") and using the version I obtained through apt-get ("apt-get install python-rpi.gpio...

playing with servos

some servos that I had ordered were delivered. the instructions suggested another brand/model of servos, but these were a much more economical (cheap).  I tried adding them to the hand: I'll have to print the "pulley" pieces that will be attached to the servos. meanwhile, I did somewhat (hackily) got the wrist to work, for now: you keep hearing the "usb plugged out" sound in the background, and that's because the servo was being powered by the arduino. the servo's power draw appears to be causing a shutdown of the device. will need a better power source for the servos. it feels like these pieces that are supposed to be plugged into the servo will have size issues. 

pwm..

I just realized that the RPi.GPIO library (for programming the Raspberry Pi's input/output) already has PWM control, giving me a much more efficient control of duty cycles... At least the previous exercise ("duty cycle testing") refreshed me on it. PWM control on RPi.GPIO: http://code.google.com/p/raspberry-gpio-python/wiki/PWM