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 Robotics / 21763
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) What if we assume that each output drives a motor, through a differential which drives a pneumatic switch and a compressor. The compressor does not care which rotational direction it is driven, but the switch does. When we are mostly up to (...) (21 years ago, 2-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) Bad assumption but it would work, the RCX is too limited on I/O to be doing that sort of stuff except in the case of simple rollers/walker. Since legs have symmetry it's silly not to take advantage of it here, you've got to use it to keep the (...) (21 years ago, 2-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) I guess we're talking different things here. You were telling me to use all three motor/sensors. I claim I only need two for my Quad242. I have to see WWW to know what you are talking about I guess, or else you lost me. Static balance requires (...) (21 years ago, 2-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) Well I was restricting the discussion to modifying my Quad242. I think you are talking about something else. I think you were proposing using all three inputs and outputs to run the motors and control switches. I was proposing using less of (...) (21 years ago, 2-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) I agree. (...) Sorry, I made -no- statement about your Qaud242. Build it however you like. You expanded the scope of my comment from general legged walker design to something specific, where it wasn't intended to go. I was talking strictly (...) (21 years ago, 2-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) Symmetry is when something 'balances', it's a kind of equilibrium. Let's look at a six legged walker for a moment and see what sort of symmetry it has. First off we have six legs and many of them (at least three in the right location) must (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) True. (...) I was just picking on you since you've spent your day publicly humiliating people (dripping with sarcasm :^) I have plenty of silly and/or stupid ideas..... Some of them lead to really great ideas. (...) No doubt. Flaws are a (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: an idea, can someone tell me if this is possible/been done before/etc?
 
(...) There's no fault involved from my perspective. The idea is to have fun. You can't do that without some sort of risk (at least I've never experienced 'fun' without some risk). The problem comes when people mix emotion/ego with curiosity. Very (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Bump switches and "aggression"
 
I mentioned a 'reference platform' for the H18 group I've been working on in a previous post, and I'm curious if anyone will share their views on how they view bump switches and 'behavior'. I'm not interested in a debate but rather a 'collection'. (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) How exactly, do you want to trigger this 'fight or flight'? It seems to me that a rabbit (for example) would use both of the methods above. If it's running along, and it's nose smacks into a tree (I mean bumps into a tree) the behavior is very (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
----- Original Message ----- From: "Jim Choate" <ravage@einstein.ssz.com> To: <lego-robotics@crynwr.com> ... (...) think (...) ### I think this is an interesting question, relating to complexity and emergent and evolutionary behavior which has been (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) You should watch my three dogs hunt. If all you've ever seen is a single dog hunt then you know nothing of how dogs actually hunt. They're pack animals, a single dog can't survive in the wild more than a few weeks. Yet three sub-200lb dogs can (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) Easy the bump switch jumps into a RNG, and it's important to understand that the output of a RNG does -not- need to be equi-probable, and it decides. Watch animals when they're startled, they don't stop and think, they jump around for a second (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
----- Original Message ----- From: "Jim Choate" <ravage@einstein.ssz.com> (...) was (...) ## The original request was to catalog opinions on bump sensors, a "state of the art". Remember the original question was: ** ... and I'm curious if anyone (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) <snip> (...) <snip> I'm very new to this particular thread, but I like Gordon's approach--directional sensors are needed. If I'm travelling forward and something bumps me from behind, I need to know that--If my conditional response is to do (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) go (...) 'bumper'. (...) my (...) me, (...) alternative. (...) There is one solution for staying 100% Lego and putting 4 sensors on the same RCX input. Therefor you should be able to sense which direction you were getting bumped. Lego made (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) Oh I wish I had some of those touch sensors! One person from rtlToronto has a set and there is much envy from me to him. Right now I'm using lamp bricks, which isn't that great, really, but does work :) Thanks for the heads-up! Dave K (...) (21 years ago, 3-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) That's nonsense! You are working on the very naive assumption that nothing in the environment is moving except your robot. If your strategy is to reverse direction when the robot bumps into something in *any* direction - then things will go (...) (21 years ago, 4-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
"Gordon Elliott" <lego-robotics@crynwr.com> wrote in message news:0f7901c3b9c8$84...gateway... (...) i can see jim's doing good job !!! he's humiliating almost everyone here keep doing jim!!! maybe you will achieve that your posts will go to null (...) (21 years ago, 4-Dec-03, to lugnet.robotics)
 
  RE: Bump switches and "aggression"
 
Just set the threshold on your pretentiometer to 50% and you won't hear that traffic anymore! Seriously, Pixel, you have been a cheerful contributor to this list for a couple of years now. You've had creative ideas that you've been most willing to (...) (21 years ago, 5-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
"Russell C. Brown [RR-1]" <lego-robotics@crynwr.com> wrote in message news:001601c3baeb$9a...apophis... (...) ok :) you are right i was too touchy sorry the threshold's set no problem some of you guys said many great words to me that is precious! (...) (21 years ago, 5-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
(...) Actually you don't, you want a different level of sensors to evaluate the environment (eg ir object sensors). You're just complicating your design by putting too many functions on each layer of sensors. For example, something bumps you from (...) (21 years ago, 13-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
Finally, I think I see the point to the 360-degree-all-purpo...-sensor... I was preparing a comment about putting a bot with only one bump sensor into an empty, small (two-foot) diameter arena and wait for it to get stuck... Then I realized that it (...) (21 years ago, 15-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
"Rob Limbaugh" <lego-robotics@crynwr.com> wrote in message news:004201c3c2be$0a...markera... (...) can (...) How can I attach lets say 4 switches so the make a binary code, (4switches should need only two ports). I want to have one switch on each (...) (21 years ago, 15-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
There was discussion of one company that made switches with analog values that could be mixed, but they were apparently either expensive or hard to find (at least there was some difficulty). But simple resistor network, say a load resistor to ground (...) (21 years ago, 16-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
For a pure Lego solution, you could try rigging up something with a rotation sensor that would have the sensor point in the direction of the collision. Suppose the rotation sensor was mounted with it's input shaft pointing up vertically - with a (...) (21 years ago, 16-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
By the way, there are 5 states, all switches off, and each of the 4 switches. (That does not count the combinations if more than one switch were triggered at the same time). Thus a binary solution would take three inputs, just one less than the (...) (21 years ago, 16-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
You could attach 2 touch sensors to each port and take a look at the raw values when different combinations of the sensors are pressed. ----- Original Message ----- From: "Øyvind Steinnes" <phoenix@online.no> To: <lego-robotics@crynwr.com> Sent: (...) (21 years ago, 16-Dec-03, to lugnet.robotics)
 
  Re: Bump switches and "aggression"
 
there's probably a way to use a light sensor to sense four different colored bricks. one for each direction. = sensor red ylw blue wht / ---\ /---- different heights of 'wedges' would lift a column, as a bumper is either slid in, or the bumper (...) (21 years ago, 16-Dec-03, to lugnet.robotics)

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