Cool thanks for that ,I'll have to see if I can scrounge up a clamp meter somewhere.

HI all

Buy now you're probably sick of me asking all these Question..... So heres another one

Has anyone got any second hand speed controllers around? 60-80a?


thanks

Build Report :

started to build the wepon this week but might have a slight problem
I was reading through the rules it says that hydrolic systems have to be pressure tested,Well all I have is a 12v pump 2 hoses and a ram,how hard would it be to get it tested? or would it need testing?

here is a picture of the system
http://www.robowars.org/forum/album_pic.php?pic_id=1317

and I have also got myself a radio,and I might go and get some drill motors next week.

I think as long as you know what you're doing and can do a full run test in an arena somewhere with protection without fail you should be alright, i'd like to see a hydraulic robot for once.
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Are all of the components designed for hydraulics? They look like it in your picture.
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So even the rain that falls isn't actually going to fill our dams and our river systems

yep sure are

Sounds good. Have you weighed the system?
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So even the rain that falls isn't actually going to fill our dams and our river systems

Na not yeat i was going to do it the sarvo

Oh well I didn't have anything better to do so I weighed it is 8Kg exactly so that means I have 5.6Kg for everything else

Doubt that's possible. Make it in a lightweight!
Although you "may" be able to do it...
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Hydraulics are another area with unexpected dangers to those unfamilair with them.

Have you heard of waterjet cutting ? Apparently a pinhole leak in a hydraulic system running at x thousand PSI can perform pretty much the same function.. especially to nice soft flesh that happens to get in the way of the fluid stream.

Its also quite tricky to make hydraulics work once the bot has been upside down (which is quite likely in robot combat) due to air bubbles getting into the system.

Finally, since most hydraulics are slow, people tend to try and build crushers with them, overlooking the fact that its hard for a 13Kg robot to crush a 13Kg robot.

The frame of the device doing the crushing has to be much stronger than the frame being crushed or you will bend yourself rather than your opponent. To build a frame capable of withstanding these forces generally requires you to significantly compromise in some other weight area (batteries, drive power, armour etc).

If you have no significant experience with hydraulics, as an EO I would ask that you take your system (and probably your completed bot) to someone who works with them as a job and get a written professional opinion that your setup doesnt have any unexpected hazards. Spending some time with such a person learning the dos and donts of hydraulics would probably be a good idea as well.

Most safety rules arent about protecting the robot in the arena, but the people in the pits around it - which is where most accidents happen.
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

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Have you heard of waterjet cutting? Apparently a pinhole leak in a hydraulic system running at x thousand PSI can perform pretty much the same function.. Especially to nice soft flesh that happens to get in the way of the fluid stream.

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Its also quite tricky to make hydraulics work once the bot has been upside down (which is quite likely in robot combat) due to air bubbles getting into the system.

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quote:

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The frame of the device doing the crushing has to be much stronger than the frame being crushed or you will bend yourself rather than your opponent. To build a frame capable of withstanding these forces generally requires you to significantly compromise in some other weight area (batteries, drive power, armour etc).

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quote:

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If you have no significant experience with hydraulics, as an EO I would ask that you take your system (and probably your completed bot) to someone who works with them as a job and get a written professional opinion that your Setup doesn’t have any unexpected hazards. Spending some time with such a person learning the dos and don’ts of hydraulics would probably be a good idea as well.

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Sounds good to me then.

I'm all for people using new technologies, as long as they learn about them and do so in a safe, intelligent manner. its part of what robot combat is all about.
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Great minds discuss ideas. Average minds discuss events. Small minds discuss people

No Worries

I was going to use this system for another project but that fell through .

So instead of it taking up space in my shead I thought I might put it to good use

That unit looks fairly safe at a guese it would probaly only run at around 300-600 psi (mabee even much less it looks likje something for lifting a truck cab or similar ) its a two directional motor ram set up (the oil gets pumped from one side of the ram to the other with a vane or gear type pump they usualy dont have an oil resivior ) so should work ok upside down. You could take it to a hydralic place and get the hoses shortened to suit your needs that would reduce a bit of weight .They could posibly presure test it for you so you have an idea what numberes to work with .
Most of those types of small systems have an over presure cut off or presure bleed by pass to protect the motor from burning out so i cant see it being unsafe in a robot .

Last edited by Totaly_Recycled on Fri Oct 06, 2006 11:46 pm; edited 1 time in total