Category: Door

Phidget motor controller.

After heading down a complex path with Arduino and a motor controller with many more features than are required I think I can simplify the build by switching to a Phidget motor controller (1064 – PhidgetMotorControl HC). Its all in one (rather than Arduino + controller), has Python (and many other) libraries, and has built-in inputs for sensors as required. The only issue with the HC is the height of the terminator block – I’m checking this at  the moment.

Updating a Twitter profile image using Python and cURL

I’ve been trying for ages to update the Twitter profile image from Python and getting lost in multipart boundary rubbish. It seems as though its a fairly ad-hoc part of the Twitter API that hasn’t ever been updated. PyTwitter doesn’t handle it currently which is being used for all the other Twitter updates being done.

Finally here is a working method using PycURL. Thanks to pieceofpy for solving the actual syntax for form file uploads.

def SetProfileImage(self, filename):
import pycurl
url = 'https://twitter.com/account/update_profile_image.xml'
head = ['Expect: ']
data = [('image', (pycurl.FORM_FILE, filename))]
c = pycurl.Curl()
c.setopt(pycurl.URL, url)
c.setopt(pycurl.USERPWD, "%s:%s" % (self.user, self.passwd))
c.setopt(pycurl.HTTPHEADER, head)
c.setopt(pycurl.HTTPPOST, data)
c.perform()
c.close()

This is the equivalent of the curl command

curl -u anxiousdoor:xxxxxxxx --header "Expect: " -F image="@/home/rossetti/door/icon-unlocked.png" https://twitter.com/account/update_profile_image.xml

EeePC arrives.

JB HiFi matched Harvey Norman’s sale price on a new EeePC 701SD. A better price than older and second hand models have been going for on Ebay this month. Hopefully I’ll be able to use the Asus online storage (10GB) in the project too perhaps for database backups.

One of the first jobs will be to install the conceptnet package and see how it performs. Then take the netbook apart and try and thin it down to 27mm.

Arduino + motor controller.

A better way to do this is using an h-bridge IC. But can I buy one in Sydney? Only Altronics and Farnell stock them.

http://itp.nyu.edu/physcomp/Labs/DCMotorControl

http://lab.guilhermemartins.net/?p=66

http://www.toddholoubek.com/classes/pcomp/?page_id=394

There is an official Arduino motor controller shield. 

And the all done solution from Lady Ada – an Arduino shield kitset (with eagle files if you want to DIY) that controls dc motors, steppers and servos for good measure.

Lady Ada – 19.50USD + 9.65/33.50PP
http://www.ladyada.net/

Fun Gizmos (v3) – shield & components 25USD + 13.85/28.85/72.52PP
http://store.fungizmos.com/

Little Bird (v3) – shield only 18AUD +7.80PP (+GST I don’t like it when they neglect to mention that until checkout)
http://www.littlebirdelectronics.com/

NKC (v1) – shield only/shield & components 4.99/10.99USD (incl. shipping comes to 17-25USD)
http://www.nkcelectronics.com/

Schematics for Motor Shield v3
http://forums.fungizmos.com/

Local store w/ Arduino & motor controllers
http://www.oceancontrols.com.au/

Parts from Farnell ~36AUD

Parts list from Fun Gizmo (v3)

  • 1 Official Arduino bare motor shield PCB V3.0
  • 2 100uF electrolytic capacitor 25Vdc
  • 4 100nF capacitor polyester
  • 1 74HC32N DIL14 Quad 2-input OR gate
  • 1 SN754410 (L293D) DIL16 (motor controller)
  • 1 74HC00N DIL14 Quad 2-input NAND gate
  • 2 3mm RED LED
  • 1 3mm GREEN LED
  • 6 100K 1/4W resistor
  • 2 2.2K Resistor 1/4W
  • 2 470 Ohm Resistor 1/4W
  • 1 1×40 .1″ mail header
  • 2 Pushbutton 6×6 

    • Car door lock actuator.

    The actuator from Jaycar is 33mm at its widest point so I suspect I will need to sand off about 6mm total. Plugging in to a 12v < 10A source throws the rod hard out or in depending on polarity.

    Just sitting down to draw a circuit diagram for the relay to control it via Arduino and I notice this article.

    Switching and reversing arduino relay shield which is exactly what is needed. Thanks!

    This looks better. Most relay circuits for Arduino seem to have transitors and diodes. This one is designed for reversing a motor. More to look at obviously.

    Arduino motor controller

    Collins dictionary asks public to rescue outdated words – Telegraph

    http://www.telegraph.co.uk/

    Fusby - short, stout or squat

    Skirr - a whirring or grating sound as made by the wings of birds in flight

    Vilipend - treat or regard with contempt

    Oppugnant - combative, antagonistic or contrary

    Embrangle - confuse or entangle

    Astergent – cleansing or scouring

    Agrestic – rural, rustic, unpolished, uncouth

    Apodeictic – unquestionably true by virtue of demonstration

    Caducity – perishableness, senility

    Calignosity – dimness, darkness

    Compossible – possible in coexistence with something else

    Exuviate – to shed (a skin or similar outer covering)

    Fatidical – prophetic

    Griseous -streaked or mixed with grey

    Malison – a curse

    Manseutude -gentleness or kindness

    Muliebrity – the condition of being a woman

    Niddering – cowardly

    Nitid -bright, glistening

    Olid – foul-smelling

    Periapt – combative, antagonistic or contrary

    Recrement – waste matter, refuse dross

    Roborant – tending to fortify or increase strength

    Vaticinate – to foretell, prophesy