Team Saint Robot Builds

[craig_colliass]

Many thanks for the information, I have just ordered one and will see what its like.


IMG_0777.jpg

Above is my first attempt at Pneumatic Muscle. the initial results are quite promising.
Operating pressures seem low about 40-60psi
Contraction is around 15-20 % of effective length, and the force though not measured, is sufficient to over power my or anyone's ability to stop it, so far. the diameter is 15mm and length just over 100mm.

I hope to take it to Maidstone so if you are there we can show anyone who is interested.

Craig

[Max]

I've been planning on trying out a pneumatic muscles in a robot for ages but haven't had an opportunity to get round to it. I look forward to seeing how this develops.

[craig_colliass]

The compressor has arrived

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I have to say for £30 it is very good I might buy one for inflating my tyres!

The performance is so much better than the small diaphragm ones you get at the petrol stations.

The size is a problem as it is about 250mm long and 180mm high. Weight is 2.2Kg But I know the handle and end caps could be removed along with some other plastic stuff that will make the thing smaller and a little lighter.

I estimate final dimensions will be just over 200mm long 110mm heigh and weight about 2Kg.

[craig_colliass]

All stripped away

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As expected the length is now about 200mm and the height is 140mm with the gauge (110mm without) this is going to be removed and replaced with a pressure switch to control maximum pressure to about 3Bar.

[craig_colliass]

Can't believe that was the last show of 2014, such good fun!! thanks to John and all the robots crew for such a good year doing the Robot Wars shows.

I'm looking forward to next year, but before that I'm looking forward to all the repairs and modifications for the 2015 season. some of which will be posted on the forum.

I think most who saw the Pneumatic Muscle prototype in action were surprised on how well it performed at very low pressure. I hope to continue trying to get the performance as good as I can. and then start mock-ups for the leg mechanism.

I think the Robot scene is going from strength to strength at the moment and long may that continue.thanks to all the guys for a great Saturday night I like being a Christmas Elf!

[craig_colliass]

I have been preparing some motor gearbox units NPC74

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One done the other to go.
For some strange reason the motors have the thinnest wires connected to them, evidently this has been a problem with these motors for a while, I have doubled up the cables so there should no longer be any problem they also have an elongated case at the back for encoders and similar as I am not fitting that, the aluminium casting has been cut down and the end plate refitted. when I got these motors I thought they were rated at about 1hp similar to the Boshes but they seem to be about 1.7hp so that was a nice surprise the smaller ones are the 1hp units.

[craig_colliass]

Nearly finished the other motor
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Have been bedding in the brushes the motor draws about 5Amps at 24v with the gearbox attached, that is not too bad running with no load for a motor that is about 1.25Kw
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[daveimi]

Are these the units the marketplace sells as "T74's"?

[craig_colliass]

Yes they are I don't know how good they are going to be as they aren't used much this side of the pond. The specification looks OK.
24v motor no load speed at the drive coupling is nearly 250rpm with a reduction of 20:1 this gives a motor speed of just under 5000rpm! the gearbox innards look like they can take some stress but you don't know till you try to break something I am fitting a 20 tooth sprocket to connect to the 40 tooth sprocket on the hubs, this will give them a reduction of 40:1 (Saint has about 34:1 at the moment)
they are to go into either Saint or Gabriel. the only thing to watch with these motors is they have very thin bolts holding the motors together so I will have to support the end of the motor somehow. If you don't try you won't know.

[daveimi]

I'd been looking at these, like the way you can just bolt them on.