Spinnerness...

[josh]

i think the idea is to create a flow through the cup so it is constantly sucking but not creating a solid seal so the robot can still drive around whilst sucking to the ground so by using tiny holes in the cup air can be sucked in and back out of the cup by the pump.

[Panzerbot]

I think now i have understand.
A vakuum pump for mor grip.
So one hase the ant in my movi

[bitternboy]

If I didn't label it properly, the yellow stuff is foam which I've got lying around. Josh, you hit the nail on the head, that was my reasoning. There's a fancy graph to show suction vs. air flow but I can't copy it because I don't have a computer at present and am doing this on the wii.

[andrea.taras]

Hello again people! I'm getting back into the subject the convo started with to ask you a question. I'm getting both this ESC: http://www.giantcod.co.uk/hobbywing-10a ... 03317.html
and this brushless: http://robotbirds.com/catalog/product_i ... 5c1377258c .
Will I need particular connectors for them? If so, can you link me some? Thanks!

[Jonny]

i just soldered the wires from esc to brushless together and soldered on a battery connector.

[joey_picus]

In my experience if the motor or the speedo comes with connectors attached, they come with a matching set to solder to the wires of the component that lacks them.

[bitternboy]

Quick question: When it comes to spinning up a blade, which matters more; Thrust or KV. I've got an eye on a few motors for a spinner and the smaller motors tend to have a higher KV but low thrust (as low as 135g at 2.8A in some cases). Is this too little to spin a disc up and would a low thrust affect the impact when your disc is up and spinning?

Sorry to dig up an old thread.

[BeligerAnt]

KV is the motor speed in RPM per volt, so a KV value of 3000 running on 7.4V would give a (theoretical) speed of 22000rpm.

Not too sure about the thrust rating. It must depend on the propellor you use! However, it must also be some sort of measure of the torque available, so more may be better.

Since the disc/weapon on most ants rarely exceeds about 50g I suspect the torque/thrust rating is not that important. The weapons generally work by storing kinetic energy in the rotating mass, in which case speed, mass and the way it is distributed are the most important things. Low torque will mean it takes longer to spin up, and may limit the top speed. In the overall scheme of things, I doubt you would notice the difference.

[bitternboy]

I might end up buying an 8.8g brushless with 3750KV with a theoretical top speed of 27750rpm. Sounds too good to be true really!

[peterwaller]

I would just say that I found a really fast inrunner motor I tried was not as good as the slower outrunners which seem to have more torque. To get the balance good enough to really run at full speed is almost impossible.