The immediate replies to Tims post were all from google, and they all elided the "[shameless]" portion. Just one more of the failings of the google interface. Have they no shame?
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It hasn't made "Read the Can't Miss List!" or special offers in their BestBetBooks in Electronic & Electrical Engineering flyers, so I'll wait until December when they dump it at 40% off. They are currently trying to push Modeling and Verification Using UML Statecharts A Working Guide to Reactive System Design, Runtime Monitoring and Execution-based Model Checking- by Drusinsky
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I wonder if that delivers any value; I'm suspicious of these flash-and-dazzle things that spend all of one page per major topic- just overview crap.
That's probably because its so hard to make any nonlinear results apply to anything that isn't the specific system that generated the results. General nonlinear results are hard to understand, hard to compute, and hard to determine whether they apply. So much of the thrust of control theory is about linear systems, and you're expected to make your nonlinear systems fit.
I like your solution for three reasons: One, it's pragmatic -- I bet the PID controller inside is pretty standard. Two, you didn't have to use many nonlinear elements to make it work right. Three, (and this is my own personal quirk), the need for a nonlinear controller arises not because the _system_ is nonlinear, but because the cost function is not x^2 -- it's an important side of nonlinear control that's not always pointed out well.
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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Posting from Google? See http://cfaj.freeshell.org/google/
Hey, today it's ranked at 32000 in books. Yesterday it was 540000. At this time tomorrow it'll be better than 200000 books that haven't even been written yet :-).
Apparently you're as much of a tightwad as me. I did discuss the pricing with my editor -- she was pretty adamant that it was the right price. Besides, you get a CD with code that not only illustrates cool functionality, but it compiles, it runs, and it's been tested & debugged. That's gotta be worth several hundred pages right there, eh?
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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Posting from Google? See http://cfaj.freeshell.org/google/
The encoder substitutes different methods of coding ascii. For example, the letter "A" can be expressed as decimal 65 or hex 41. The encoding is particularly effective if the "mailto:" prefix is included.
A browser automatically restores the string and loads the email client, but email harvesters apparently don't have the capability to do any decoding. Maybe it takes too long, or they figure there are too many different methods and they don't have time to see if the decoded address is valid.
I used to get large amounts of spam from my web site when the email address was in plain ascii, but haven't got a single spam message since I changed to this encoding method several years ago. One problem is when someone saves your address in their client, and they subscribe to some chat page that requires they download software. The software then goes through their address book and sends all the addresses to a spam site. You can tell what happened when you start getting spam messages saying so-and-so is waiting for you to join her chat site. In this case I used several different email adresses with spammotel so it was easy to see who had the problem.
When your email address gets on a spam list, it is useless. The only solution seems to be to delete it and put a new one on your web site. As long as you tell everyone to use the contact page instead of saving your address in their client, they will be able to contact you with no problem. But anyone as popular as you should plan on changing email addresses regularly.
SpamMotel is a bit of a pain when you want to reply to a message, so you need an ISP that allows you to manage your own addresses. I recently switched from sympatico to concito.net. This is the very best ISP I have ever seen. They charge $8.95/mo for 56k dialup, have local numbers all across the US and Canada, offer 20 email addresses you can manage yourself, and have a three year expiration on newsgroup postings, including binaries. So you can continue posting your pdf schematics to abse, and I can still get them years later!
They are having a small problem with logging on newsgroups right now, but they say it's their upstream provider. They have been very responsive in the past, so I'll let them play for a while before starting to make load noises.
I think my hit was a "manual" job. I received an E-mail asking me to confirm my "subscription" to a blog site.
I then received _one_ direct spam, but no more so far.
I use the E-mail forwarding capability of my website, with currently
181 different addresses for the various accounts I have.
Most of my E-mail addresses never require a reply. For those that do I simply put a "persona" in place in Eudora.
My website costs me $19.95/month plus the Cox HSI is $39.95
...Jim Thompson
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| James E.Thompson, P.E. | mens |
| Analog Innovations, Inc. | et |
| Analog/Mixed-Signal ASIC\'s and Discrete Systems | manus |
| Phoenix, Arizona Voice:(480)460-2350 | |
| E-mail Address at Website Fax:(480)460-2142 | Brass Rat |
| http://www.analog-innovations.com | 1962 |
I love to cook with wine. Sometimes I even put it in the food.
Or something -- I used SciLab to do the design exercises in the book. SciLab is a free MatLab replacement. In many ways it's better than MatLab, although it does fall down when you start trying to edit it's block diagrams (I really need to convince the SciLab team to do something about that).
There's three classes of stuff on the CD: A SciLab install, SciLab code that generates many of the figures in the book, and incidentally provides examples of using SciLab, and a bunch of C code from chapters 9 and 10. The C code from chapter 9 is sample code for implementing swept-sine frequency response measurements from within the controller. The C code from chapter 10 is a set of code for implementing fractional arithmetic, plus a set of useful control system blocks implemented for integer arithmetic, fractional arithmetic, and floating point arithmetic. One could take my sample code and use it as library code for the core of a controller.
Jerry mentioned looking at other things I've written -- if you look at my website you'll see many articles which directly contributed to the book. "Z Transforms for the Embedded System Engineer" became the seed from which the z transforms chapter and the design chapter grew. "Measuring Frequency Response" produced the chapter on measuring frequency response. "Using Block Diagrams in Control System Design" grew into the block diagrams chapter. "Controlling Motors in the Presence of Friction and Backlash" is in the "Nonlinear Control" chapter, along with a bunch of other stuff.
There isn't a word in there that's lifted from "PID Without a PhD", but I did make darn sure that the design chapter covered PID design.
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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Posting from Google? See http://cfaj.freeshell.org/google/
Perversity? It certainly is a PITA. If you check out my web site there are a number of articles that _aren't_ linked to embedded.com, and which put the figures in the text so you can have a chance at seeing them in the right place.
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Tim Wescott
Wescott Design Services
http://www.wescottdesign.com
Posting from Google? See http://cfaj.freeshell.org/google/
You guys really are tight wads. If you take even one idea from a book, it is a bargain. I just got back from CA where Tim's book was released. I usually buy at least one book every time I travel to Silicon Valley or San Franscisco. One year I spent $900 on 9 books.
I am happy to report that I have helped Tim move up the best sellers list. I have an autographed first edition and printing of Tim's book. Someday, when Tim is even more famous, I will sell it for a huge profit.
For the moment, we can all be content that we are helping Tim with his Porsche payments. I'm sure we will all see him on late night TV soon.
My suggestion to everyone is, buy Tim's book. You'll be able to tell everyone, you know a famous author! If you also buy Rick Lyon's book, you will know at least two famous authors. This will probably make you very popular and some of you will now be able to date beautiful women that you couldn't even talk to before.
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Al Clark
Danville Signal Processing, Inc.
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If you really feel that way, I think you ought to ask for your money back, Chris.
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