I managed to pull some motivation together and got some work done on the robot. I started testing a miniature H-bridge drive, but there are some problems with that. I’m not sure whether it is the breadboard or the components so I will have to look into that another time.
I started thinking about using modified servos as drive motors. This involves (in the crudest version of the mod) cutting the shaft off the feedback pot and removing the stop on the output shaft cog so it will spin through 360 degrees. Modified it fine but could not get it to spin at all. Went back a step and found that there was no serial data to the servo controller. Of course I connected ttyS1 instead of ttyS2 (man I love how much IO you can do with the gumstixs!) so after I corrected that the data began to flow. Still no servo action though.
Now I thought lets bring out the big guns. Out came the CRO and I hooked her up to the servo output on the controller to see what signal was present. More pictures after the jump.
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Thought I better get some work happening on my robot. Shown in the picture below is the test setup for the ultrasonic range finder. It has serial and analogue outputs and can detect from about 10mm to 3m with reasonable accuracy (I think; I probably better go and find the data sheet). I decided on using the analogue output; I prefer reading an ADC than some serial data.
I wrote a small program using the i2c-io library to gain access to the robostix’s ADC lines over the i2c bus to the gumstix. It would read the ADC and print the returned value so I could verify the accuracy and the highest frequency that I could poll the ADC.
Edit: I can not spell, sorry!
I had a problem today that the signal strength meter I had borrowed only did terrestrial tv and not satellite signals. Now anyone who has aligned a dish without a satellite finder will tell you it is not the easiest thing to accomplish.
I was then faced with the problem that I did not have a small tv I could take outside and connect the set-top box to and view the signal strength meter menu. Thinking my sister is home with her Mac I might just be set.
So I setup iChat with Bonjour on both, sat her Mac in the lounge room facing the tv and took my Mac on the room and volia it worked like a charm. And even better, I was able to give directions to my brother downstairs through the iChat session! See the pictures after the jump
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Well it finally arrived (for us in Australia anyway). Like all the reviews, the store is far better than before. What is upsetting to me is there are still no new movie trailers. I always liked downloading a few HD trailers and checking out whats in the pipelines as far as movies go, but come on Sony, lets get some new stuff.
And speaking of new stuff, when is Apple going to release tv shows and movies to Australia? I would buy an Apple TV in half a second if they would pull their finger out and release it here. Channel Seven/Prime and Ten/Capital already show most of the latest American shows with minimal or no delay. So Apple, what is the deal then? (Unless you are thinking of releasing that part of the iTunes store when the iPhone releases here; I am not convinced though.)
Got a nice old cheap CRO today from a colleague in Wagga. 20MHz bandwidth and the original instruction manual for only $40. Not bad I say. Should work well with the development work on my robot. See it in all its majesty and splendor below!
I got Rockbox onto my 5G iPod yesterday. Let me say it is nice. Uses the iPod screen real-estate far better than the Apple firmware and has quite a few more features (OGG and FLAC FTW!).
Sure I can understand that Apple need to make the iPods very simple to use but couldn’t they implement a Pro interface. They have “Pro” features on the Mac, why not on the iPods?
I’ve put the link to the old car pc page back on the site under Site Links. Just in case anyone wanted to visit it still.
I know its been awhile since Twitter came out but still, its pretty cool. I’ve started to update more frequently on Twitter. What I really like is not only being able to follow friends and podcasts/blogs but being able to track keywords on the public timeline. Its pretty cool seeing all the people’s views on XKCD comics…
Anyway, I’m hanging out on Twitter under the name matqua (what else!)
Hooray! I have finally got WordPress installed and running correctly. Now lets see if its nice page formatting can keep be blogging.
Matthew
