Earthwormjim's Stuff

[BeligerAnt]

Be interesting to find out just how far off the nominal kV value you are with a typical antweight spinner as a load...

[Remote-Controlled Dave]

Great robots as always Jim. The Barbarian is like the antweight Code BLACK and looks gorgeous.

[earthwormjim]

Thanks Champion Dave. Just looked up Code Black,very nice.
Very similar in principal.

[Andrew_Hibberd]

Looking good as always Jim. I have had a quick look at ducted fans, they are really really really thirsty. How much downward force do you get from it and how hot are the batteries ?

[earthwormjim]

Thanks Andy.Yep,they are really really really really thirsty! I have a 20A esc,with 750mah lipos.It gets a little toasty,but the only thing that gets very hot is the battery connector.
I will do a thrust test tomorrow,when I have an empty house,as it sounds like Concorde taking off!

[earthwormjim]

Right,did some testing with FANTOM This morning.
It weighs 145g,and at full pelt,on 2s,the fan produces 160g of downward thrust,which settles to 130g after 5 seconds,but will stay at 130 for a good few minutes.
I cant fit any more than 2s in there realistically,while retaining any duration.
But the fan also produces suction.There is a 1cm gap around the bottom of the robot,on 3 sides,that supplies air to the fan.When the robot is placed on my 4" cube,and the the cube filled with weight.It can lift over 500g.
All in all,it seems to work very well, big spinners are the main worry,it will be really interesting to see how it works in the arena!
I now have the 30:1 super HP Botbitz motors,coupled with the Botbitz 10A esc's,so it really flies now.It does self right,but it is a bit of a random event,quite entertaining though!!
Cheers Jim

[PJ-27]

Is self righting it just blowing itself back over?

[earthwormjim]

Is self righting it just blowing itself back over?

Yep! sometimes it travels about 3 feet through the air while doing it! But I think the "stabilising fins" should reduce the area needed,by keeping it from being completely inverted at any time.
Thats the plan,anyway!

[PJ-27]

That's awesome! Video?

[earthwormjim]

Okay,video here...http://www.youtube.com/watch?v=hohbcZ6o ... ture=g-upl
Might take off the fins,as looking at the video,the robot has to flip itself over the front scoop this way,which is the most difficult way to go.I will have to think of some way to point it in the opposite direction when inverted.