Back in 1991 I was part of a venture funded fabless semiconductor startup company - American NeuraLogix located in Orlando Florida. The company focused on developing semiconductor products e.g. Fuzzy logic controllers, Fuzzy Pattern generator and Neural Networks. The products worked well...but the market needed time to adapt to this new technology.The company eventually exited through acquistion.
Fuzzy logic is alive and well in space exploration in that is lends itself to building reliable control systems that function in the presence of uncertainty or ambiguity. A prime example would be in the unmanned surface exploration of Mars of supporting autonomous maneuvering since radio communication involves lengthy delays. Without exact knowledge of where rocks, boulders, and crevices are, rule-based fuzzy logic controllers consisting of a finite set of control rules which are processed by applying what is referred to as approximate reasoning, i.e. general terms such as large, deep, very deep etc., are the best current solution for collision avoidance next to actually having a human pilot at the controls.
Thanks, pomartel. That Bob Pease article is awesome! Here is a snippet:
When I do get this working really well, I'll send a videotape to Dr. Li and Dr. Ji - just to show them how a beam balancer can work well. They claimed they got their best results because they didn't use any models. Mine runs well because I was able to use simple models: a rolling ball is a double integrator. They claimed their Fuzzy Logic was able to triumph over the nonlinearities of a tilted beam. Well, the approximation that sine of tilt angle = tilt is only nonlinear by a few percent. They still can't servo the ball to any place on the beam as fast as my PID2 controller.
I would have loved to see Mr. Pease and Mr. Li in a room showing off their respective contraptions!
Fuzzy Logic was just a method of using hysteresis combined with overlapping state values to smoothen the transfer of state transitions. The only thing Fuzzy about it was that people thought it was something new.
I remember getting an FL dev kit from Mot for their HC05 back in those days...I'm moving again after a long time in the same house and just threw it away a couple weeks ago. Just had too much stuff piled up and, well, the 8051 may still be around, but days of the HC05 have come and gone.
I have always seen probability as a predictor of future events ("What are the chances that the Cubs will win the World Series?"). Fuzzy logic is a descriptor if current events ("Is that guy really bald, or just partly bald?"). Two different kinds of uncertainty. Two different processes to deal with them.
I remember being interestred in FL early on, but it seems there was a certain amount of hype. Bob Pease did a few columns on FL, among them:
"Fuzzy Logic" the term has a tinge of nostalgia to me also as it reminds me my days as engineer when I was working on control applications for white goods - washing machine, fridge etc. That time the term had caught -up the imagination of marketing guys so much that it had become a key word to be used in commercials to show that Fuzzy logic base appliance were superior.
As the customers found out that there was no great difference in performance or the UI , that wave slowly faded .
NASA's Orion Flight Software Production Systems Manager Darrel G. Raines joins Planet Analog Editor Steve Taranovich and Embedded.com Editor Max Maxfield to talk about embedded flight software used in Orion Spacecraft, part of NASA's Mars mission. Live radio show and live chat. Get your questions ready.
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