Rapha Race Controller

Written by  on June 24, 2008

Rapha Sportswear has a stationary race controller prototype that they need replicated for an event next week. The first step int this process was to break out the original design into 3 boards one for input processing one for the stepper drivers and one for the processor itself. Since the customer wanted to be able to modify the code themselves in the future and expand the system an Arduino or Wiring compatible board will be used.

(The completed project)

Motor Boards

The motor boards consisted of 4 darlington transistors on the best performing heat sinks I could find.

The I/O – Processor Board.

The I/O Processor board consisted of to schmidt triggers to clean up the input and a usb to serial connection for programming and future use. The board also has 3 free ports for future use.

The Inverse Map

Written by  on June 18, 2008

In the course of my duties as a biological modeler (whatever that may mean to you, my dear reader; were you to exist, of course) I am sporadically called upon to wax explanatory on the relation between generators (abbreviated and unitized as “gene” in some domains) and phenomena. The path from generators to phenomena is called the “forward map” and, perhaps obviously, the path from the phenomena back to its causes, the generators, is called the “inverse map”. It is largely the subject of plectics ¹ (a.k.a. complexity theory) to discover, use, and make repeatable, methods for accurately following these two paths. A primary premise of the computationalist approach to plectics is that the forward map is not so straightforward. I.e. beyond a certain degree of simplicity, it is not clear what phenomena will emerge from the generators. And this premise is emphasized because it is so often forgotten. It is the reason Chaos theory, fractals, and games like chess are so maddeningly interesting.

Similarly, the cyberneticists have an emphatic premise: that complexity comes about through feedback loops. Again, beyond a certain degree of simplicity, it is not clear which part of a system is the cause and which is the effect. Phenomena are exacerbated with positive feedback and dampened with negative feedback.

Both emphases are appropriate and the fact that we even have a distinction between computationalists and cyberneticists is an example of specialization gone mad. ² Both require the notion of loopiness and the somewhat occult nature of both the forward and inverse maps. But the loopiness is often a more difficult concept to grasp.

This article challenges the notion that a complex forward map is sufficient to realize or explain a complex system, especially one so full of occult paths and loopiness (including trans-hierarchy) as multi-cellular life. And I am very happy that such an article has made it into the mainstream news.

1. Murray Gell-Mann tried to install “plectics” in the vernacular, but failed. I buy Murray’s argument and try to use “plectics” whenever I can.

2. Not that I would advocate for huge box stores like Wal*Mart where you can buy diapers, car batteries, and bread all in the same trip or anything. In fact, such lack of specialty disgusts me. But there is something to say for, e.g., the general practitioner or renaissance man (sorry, I just can’t replace “man” with “person” in that phrase) who can think holistically … synergistically … about a subject without her (that should make up for the gender bias) prejudices kicking in to keep her from escaping her current thought rut.

Happy Birthday to Me!

Written by  on June 12, 2008

I am old. I won’t say how old exactly but I am half way through a few experiments. Life, work.

It makes me very happy that three of these experiments will be funded as Tempus Dictum Projects.

  1. The Dorkboard.

  2. The Benito Serial Programmer

  3. The Arduino Cult Induction Series.
    (Next Induction Sunday June 22)

I would like to thank Tempus Dictum for the opportunity to work on these items.

I am a very lucky man.

Write Locally Post Globally

Written by  on June 3, 2008

I like wordpress.

It allows me to do much of what I post on the web without having to look at the underlying html and still letting me at the html. In fact I use WordPress to to post on Dorkbots Drupal pages. It is easier than hand rolling html and the new wordpress saves your drafts. This is no small issue: As I was reminded at 2:30 monday morning as Drupal timed out the session that I was writing on and ate my post. Between that and the Eagle files I was working with I lost most of sunday nights sleep. The other issue is portability.  So last night I ran up mysql, unpacked the latest wordpress into my home directory and reconfigured the apache daemon that comes with leopard.

I plan to get more done and loose less sleep.

The Really Really Bare Bones Arduino

Written by  on June 3, 2008

This has been reposted on dorkbotpdx.org

A few weeks ago I bought the last of the Really Bare Bones Arduino rev A boards from Brian at Wulfden (http://wulfden.org/freeduino/freeduino.shtml) I now have enough boards for one more workshop and then we have to reevaluate the boards which are avaliable. Pictured below is a finished board from the first “Arduino Cult Induction Workshop”

In addition to letting me clean out his new old stock Brian threw in one of the “Rev B” boards so I could check it out. Unfortunately I don’t like it.

The new board is almost 3/4″ of an inch longer than the original. Most of the new space is dedicated to room for a power jack and a regulator. Things that I never use. The design is supposed to allow you to cut the power jack off as well as the regulator. Notice in the finished board above that their is space for a big old reset switch. When the original Arduino came out you had to reset the board to get it into the bootloader. However in the past year or so all the new boards have been using the dtr signal run through a capacitor to pull the reset line so the switch is wasted space. The original board made up for this space by adding ample ground and supply connections. The new board adds another 1/8″ and gets rid of these.

As I was grumbling about this Mark Gross suggested that I just roll my own.

So we are back to the drawing board. Above is my pen markup of the changes that I wanted to see done to the original Really Bare Bones Arduino and below is the draft of the rework to scale with the RBBB rev B.

Now comes the fun part The cost of goods sold and a business case.