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Unread 15-01-2013, 23:29
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Re: 3rd level climb even possible?

Run out of battery power? No way.
Let's do some math:
150 lbs ~= 70 kg
Assume you want to raise your robot 2 meters (78 inches)
PE = m*g*h = 70 kg * 9.8 m/s^2 * 2 = 1400 Joules
The battery has an 18 Amp-hour capacity (although you don't this much out of it in practice).
18 Ah * 12 V = 18 * 12 * 3600 Volts*Amps*seconds = 78 kJ
So climbing would use just under 2% of your battery power.

Or, looked at another way, let's assume your robot has a maximum speed of 4 meters per second (13 feet/second). To accelerate to top speed requires
KE = 1/2 * m * v^2 = 1/2 * 70 kg * (4 m/s) ^ 2 = 560 Joules
So, if we pretend that all our mechanisms are frictionless and 100% efficient, sprinting from one side of the field to the other three times is very roughly equivalent to climbing the tower.


Quote:
Originally Posted by F22Rapture View Post
I could definitely see using pneumatics to actuate claws, but aren't they mostly useful for pushing and not pulling, as the majority of the movement in the climb would be?
No. In fact, I've heard it argued that you should always use pneumatics to pull, rather than push, because that way you don't put the rod into compression and risk bending it.
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