View Single Post
  #5   Spotlight this post!  
Unread 04-05-2003, 08:32
Lloyd Burns Lloyd Burns is offline
Registered User
FRC #1246 (Agincourt Robotics)
Team Role: Engineer
 
Join Date: Jun 2001
Rookie Year: 1997
Location: Toronto
Posts: 292
Lloyd Burns is an unknown quantity at this point
I've always used 746 W = 1 H.P.

A 400 kW Mercedes engine has 300 H.P. in the U.S.

And since electric motors are really efficient, use Watts Out = > 0.9 times Watts In = Volts x Amps. (The approximation is useful because your input data are approximations too.)

If you have to figure Watts out, you can also use torque times revs :

W - F x d = F x [v x t] = (T / arm) x (rps x arm x 2 x pi)

J = N x m = (N.m/m) x (cirumferences-per-second x length of circumference) = (N) x (length) = F x d = W