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Subject: 
Re: Brainstorms
Newsgroups: 
lugnet.robotics
Date: 
Sun, 11 Aug 2002 18:32:46 GMT
Viewed: 
680 times
  
OK, I've been watching this thread for a few days (I am LUCNY's "Expert
Lurker" after all !) and refining some ideas that I've had for a while in
hopes that I can contibute to this dicussion in a useful way.  Please keep
in mind that I'm a Mechanical Engineer by education and a Computer Software
Engineer by profession, so low level electronics are not really my area of
expertise.

I've read statements by several people expressing the desire to have
something that has the scalability and (to borrow a term from audio
entusiasts) the "Dynamic Range" of traditional LEGO(R) bricks.  I
whole-heartedly agree with this and want to add my vote to that tally.

I think I2C is the way to go.  It's cheap, simple, and time-tested.

That said, I'd like for BrainStorms to be backward compatible with Technic,
Mindstorms, and Spybotics.  Most people aren't going to embrace new tech
unless the new stuff can "leverage their legacy platforms."  (Yes, I've been
in meetings with IBM consultants all week)

So how do we use I2C and still interoperate with Mindstorms, etc. ?  We need
a IAB (interface adapter brick) that converts the IR communications to I2C
signals.  I've been trying to figure out how to do this on my own for a
while now, but like I mentioned, it's not my forte, so I haven't gotten very
far : (

I envision having several types of IABs (Interface Adapter Bricks) :
1.  An IR to I2C IAB
2.  A VLL to I2C IAB
3.  A motor IAB
3.  A passive Sensor IAB
4.  An active Sensor IAB
5.  A serial EEPROM IAB
6.  A USB to I2C IAB
7.  An RC servo IAB
8.  A pneumatic valve IAB

John B. and others mentioned the need to identify nodes on a distributed
network and I've got an idea about how to do that : We design every I2C
capable module or IAB with a connector that allows one to attach a NIB (Node
ID Brick) to it.  The NIB could have an eeprom in it to store it's NID (Node
ID) or even have a bunch of dip switches on it so one could change it's NID
as needed.  Either way, changing the NID of an I2C node would be as simple
as swapping NIBs.
The guys with the 3-axis CNC did a nice job of engraving text for the name
tags at Brickfest, and I think that'd be a professional way to mark NIBs for
quick visual identification. IE simply engrave the NID on the side of the
NIB.

For interconnections between modules, I'd suggest we stay with the 9V plates
and leads that LEGO(R) makes now for most things.  I know they're not the
cheapest, but they're easy to use and easy to mark using different color
tiles.  People have already found creative ways of making homebrew
conenctors that are compatible with them so price might no be an issue
anyway.  I think we can send I2C signals through them with no problems and
we're already accustomed to using them for either power or data.   Custom
rotary connectors with slip rings would be a godsend, though !   I'm working
on an adapter to convert LEGO(R) wires to RC battery pack connectors.

    The discussion so far has centered on electronics and communications
methods, but I think BrainStorms should extend LEGO(R) in the mechanical
sense as well.  Anyone who a tried to build something large or powerful out
of LEGO(R) parts has either broken things or cursed alot.  LEGO(R) has given
us quite a few simple machine elements to work with, but we more things like
John B's planetary gearsets, drive rings with internal gear teeth,
concentric shafts, etc.

    We also need stronger parts. Technic beams, axles, and turntables are
great, but they're too easy to break : (   I've been making replacement
beams out of 6061-T6 aluminium for some of my chassis parts and I'm working
on getting a bunch CNC machined. I've found that 3/16" ground steel shafting
runs nicely in technic holes, but I haven't found a cheap source for spur
gears in the same metric pitch (module) as LEGO(R).  If we had them, we'd be
able to mix and match freely.  I've been trying to come up with a way to
make inexpensive LEGO(R) compatible pillow blocks for bearings etc.

    Being able to incorporate structural elements from other building
systems would be great.  Purists will wretch, but one can do alot with
K'nex(R) and Sploids(R) let one build them into LEGO(R) creations.  Try
them, you'll like them.  I've designed some adapters that let one use
Construx(R) parts with TECHNIC, but getting them produced in quantity seems
to be an expensive proposition so I've resorted to just drilling holes in my
construx lately.  I've got to look at this again though, because it very
easy to build large/light/strong structures out of Construx(R).

    Secure fasteners are a necessity, too.  Like it or not, technic friction
pins come loose and pop-out  : (  I've been reinforcing pin connections by
running #4-40 machine screws through the center and using washers to clamp
the beams together.  It works well, and even allows one to use Erector set
parts, but purists will no doubt curse me for it.

I guess I'm done rambling for now : )

HTH,
-JSM



Message has 1 Reply:
  Re: Brainstorms
 
(...) So I imagine the need for a brainstorm brick that has a standard Lego wire connection on the top and a little I2C chip inside that would interface with existing motors and sensors. This would certainly be needed because nobody wants to butcher (...) (22 years ago, 11-Aug-02, to lugnet.robotics)

Message is in Reply To:
  Brainstorms
 
Ok. I've seen a similar ebb and flow of ideas for modularization in this newsgroup before. The difference, is that now, most people who are reading this a probably well familiar with the RCX, Mindstorms, etc etc. The subject of this post is intended (...) (22 years ago, 8-Aug-02, to lugnet.robotics)

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