A PIC-Based Scripted Robot System

Posted in making and hacking, robotics on January 7th, 2013 by Samuel Kenyon

The last time I used the aforementioned scripting framework was in the robot system described here. It was intended for a spherical robot, however, I also used an old RC truck chassis for testing. It was fairly generic—there wasn’t anything specific to spherical robots in the board design or programming, with the exception of the size and shape of the board which was made to fit in the sphere shell.

The Board

My embedded robot control board.

My embedded robot control board.

This robot used an 8-bit microcontroller (uC) based board that I hacked together. All of the robot code, including comms, the script engine, sensor interaction, and motor control ran on the uC. There was no in circuit debugging / programming; I used a separate device programmer (specifically, the EPIC Plus Pocket PIC Programmer with the 40/28 pin ZIF adapter). The uC I used was a Microchip PIC18LF458.

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Languages, Assemble!

Posted in making and hacking, programming, robotics on October 9th, 2012 by Samuel Kenyon

Look what I found in my closet:

Motorola 68HC11 on an eval board made by Axiom Manufacturing

This is my old Motorola 68HC11 microcontroller board. Here’s a close up photo of the microcontroller itself:

Motorola 68HC11 Microcontroller IC

For those who aren’t familiar with these terms, a microcontroller is basically a computer on a chip. They are often very tiny and low powered, and are ubiquitous whether you realize it or not.

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Should We Worry About the Anti-Makers?

Posted in culture, making and hacking on February 7th, 2011 by Samuel Kenyon

As a riff off of Matthew T. Dearing’s “We Are All Makers” post, I wanted to rant about the anti-makers.

I do like the fact that there are so many makers and hackers; I’m not sure if their numbers are increasing as there’s always been craftsmen and hobbyists, but I hope so.  Certainly it’s going on a lot even physically near me (in Cambridge MA), and I am sometimes a maker—I’m into building robots and costumes (and steampunk costumes).  Some are moving into new realms, such as the DIY bio-engineering activities.

It’s really unfortunate though how many pinheads are downright frightened of the output of makers and hackers.  For instance, in Boston people waste the time of bomb squads to investigate benign glowing objects such as the Ignignokt LED signs placed by VJ Zebbler (who is quite a nice guy; I run into him sometimes in Boston) for a marketing campaign in 2007

Boston Police display the ATHF advertisment

and the LED board on a shirt worn in an airport (also 2007) by MIT undergrad Star Simpson.

Boston Police display Star Simpson's LED shirt

It’s not limited to Boston, of course—when I went with an MIT team to San Diego several times with our autonomous underwater vehicle, there were those observers who claimed we had some sort of bomb.  But they were half-kidding and didn’t call the police on us.

It’s really scary that even in a college town full of hackers and makers and researchers (and trust me the stuff in labs looks much scarier than a simple LED board), and we have idiots who think glowing lights will explode and that exposed circuit boards (or even breadboards) == terrorism.

Perhaps I’ve created a straw man—is there anyone really so extreme that they can’t stand anything DIY?  Or is it just that each person prefers their DIY hobby, but is easily intimidated by others’ hobbies that they don’t understand?

Or is it that some people don’t want to understand weird and pointless making and hacking—as Dale Dougherty said in the TED video referenced by Mr. Dearing, a lot of making is done for reasons the makers make not even know.

Are people afraid of glowing boards and exposed wires simply because that always accompanies a bomb in movies?  The sad truth is that improvised explosive devices (IEDs) do exist in real life; warfighters in the Middle East encounter them (sometimes tragically) every day.  But the grotesque paranoia about complex and/or electronic DIY projects that seems to have gripped some people in the US is dangerous.

The reason the fear is dangerous is that makers shouldn’t have to worry about being arrested and/or shot because some dimwits are afraid of the “magic” which is normally covered up behind shells of molded plastic.


Image credits:
1-3. Unknown.
4. Bunnie

Cross-posted with Science 2.0.

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TRONtastic New Year’s Eve and Human Factors of Crotch Access

Posted in interaction design, making and hacking on January 1st, 2011 by Samuel Kenyon

I improved my TRON:Legacy-esque illuminated vest and added some illuminated leg cladding. Here is a photo of me from last night (New Year’s Eve):

Me at GALACTICA: A TOGETHER NEW YEAR'S EVE @ Think Tank, Cambridge MA

What Worked

This time the vest front and back worked without fail for several hours.  The overall design worked—everybody either understood the TRON reference or thought it was cool even if they had not heard of TRON (yes, there are many people who have no clue what TRON is despite all the advertising).

The leg cladding looked really cool, but it only worked for a few minutes.

leg cladding

What Failed

One point in the EL wire on my left leg right before the knee failed before I even got to the destination.  After a while the EL wire next to that one also broke.  Since the leg cladding was one long wire, this caused my entire trousers to be conspicuously not shining.

partially illuminated left upper leg plate

partially illuminated upper leg plate

So I had to walk around and dance with a bunch of cardboard strapped to my legs for no reason.

the broken connections

Human factors of crotch access: Another problem with the cyber trousers ensemble is due to rushing at the last minute I used just one long wire for both legs instead of two.  This resulted in an illuminated wire going straight across my fly, a clear violation of human factors.  After all, I would be drinking and that will inevitably result in needing to urinate, and hence needing to open my fly. Also if I wanted to illuminate my crotch I could come up with a much more attractive scheme than a wire going straight across.  So my quick fix was to cover it with a black wire shroud and push it against my belt, but that in turn probably made the strain on the EL wire much worse.

The arm band: I figured the tiny connector and wires on my arm band would probably fail, and sure enough they did.  I had added some tape as strain relief but it wasn’t enough:

broken wires (pulled out from the heat shrink)

Lessons Learned

Having dealt with lots of wires and connectors in the past on robotics and wearable computers, I knew that the connectors and wires should be robustified, however I ran out of time before the event.  Also, EL wire really does not handle flexing and pulling very well, so I will pay special attention to that.  Also, a more robust solution than having one long EL wire for both legs would be to have separate EL wires so that if one fails the other will stay illuminated (it’s somewhat annoying though to solder EL wire because you have to scrape the phosphorous off the center lead).

Also, making the cardboard attachments for my legs forced me to figure out how to make crude patterns.  Interesting, but certainly not something I’d want to do all the time!

So, next time we will see what else I can come up with to improve this getup before I get completely bored with it.

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