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Basic Stamp Educational Board Cannot Run without USB cable — Parallax Forums

Basic Stamp Educational Board Cannot Run without USB cable

AtomizeAtomize Posts: 2
edited 2010-07-14 18:03 in BASIC Stamp
Hi All,

I am an undergraduate from a university in Singapore.

My project team is currently working on th pole balancing robot. We are using the Education Development Board (USB).

It can't seem to run without the USB cable. Anyone knows what's the issue with this? Software or hardware?

Also does anyone know what the rubber wheels used in toy kits are generally made of? What is the poison ratio, youngs modulus and density?

Thanks.

Regards,
Murtaza.

Comments

  • allanlane5allanlane5 Posts: 3,815
    edited 2010-07-08 13:52
    I think you mean "poisson ratio", because they're not allowed to have poison in them.

    Not being able to run without the USB cable plugged in is either a power problem, or a grounding problem -- grounding usually.
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2010-07-08 18:39
    Agreed...it sounds like a low battery. What can happen is the board will leech power from the USB. Try replacing the battery and see if that helps the issue.

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    Chris Savage

    Parallax Engineering
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  • Spiral_72Spiral_72 Posts: 791
    edited 2010-07-08 20:19
    allanlane5 said...
    I think you mean "poisson ratio", because they're not allowed to have poison in them.


    Phooey, you beat me to it.... lol.gif

    The wheels could really be anything. ABS will be relatively hard, it could be acetal, Polypropylene of HDPE/UHMW if they are somewhat gummy feeling, HDPE/UHMW if gummy feeling, but rigid. Phenolic, Nylon......

    My guess would be HDPE for the wheels if they're plastic.... If it's rubber like you say, I dunno much about that. Neoprene? if it's soft.

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    "puff"...... Smile, there went another one.

    Post Edited (Spiral_72) : 7/8/2010 8:28:35 PM GMT
  • Chris SavageChris Savage Parallax Engineering Posts: 14,406
    edited 2010-07-08 21:09
    Spiral,

    Did you reply in the wrong thread?

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    Chris Savage

    Parallax Engineering
    ·
  • AtomizeAtomize Posts: 2
    edited 2010-07-09 03:09
    Hi Guys,

    Thanks for all the replies.

    I solved the issue of not being to operate without the USB cable. The cable making the common ground between the board and motor driver board was lost. When I reconnected the grounding, then it was all good.

    The tyres that I am using are hard and not sticky. How would I know if they are plastic or rubber? I think it is rubber. I am not so sure.

    Regards,
    Murtaza.
  • FrohmanFrohman Posts: 10
    edited 2010-07-12 23:53
    and yet poison seems to make it into toys anyway...

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    MAGGOTS!
  • Spiral_72Spiral_72 Posts: 791
    edited 2010-07-14 17:54
    Chris Savage (Parallax) said...
    Spiral,

    Did you reply in the wrong thread?

    No sir smile.gif

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "puff"...... Smile, there went another one.
  • Spiral_72Spiral_72 Posts: 791
    edited 2010-07-14 18:03
    Atomize said...
    Hi Guys,

    Thanks for all the replies.

    I solved the issue of not being to operate without the USB cable. The cable making the common ground between the board and motor driver board was lost. When I reconnected the grounding, then it was all good.

    The tyres that I am using are hard and not sticky. How would I know if they are plastic or rubber? I think it is rubber. I am not so sure.

    Regards,
    Murtaza.

    Without any disrespect intended.... what does it matter? You might be able to arrive at some friction coefficient but testing, but it still doesn't seem to matter much. I guess I don't know what you're doing with the wheels either.

    If the wheels are injection molded (is thin wall with a cavity inside and probably webs for structure) I'd say most surely plastic of some type. If they are solid with a hole bored through or somehow sandwiched by a hub, I'd have to vote a hard rubber

    I'd say try em' and if you need more traction, add rubber bands around it or swap the wheels out for something else. The grocery stores sometimes use ~3/4" blue rubber bands on brocolli and the like that would probably go around wheels up to about..... ummmmmm.... 2.5" dia or maybe 3"??

    ▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔▔
    "puff"...... Smile, there went another one.
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