On Sat, 2013-03-30 at 17:34 -0400, Gene Heskett wrote: > On Saturday 30 March 2013 17:32:05 cogoman did opine: > > > On 03/26/2013 01:21 AM, Gregg Eshelman wrote: > > >> I am not sure you will see good acceleration. In fact, it is > > >> > > >> >always > > >> >going to be less than 1g. This is because for any faster > > >> >acceleration > > >> >the strings go slack as the weighs don't fall fast enough. > > > > > > No need to go anywhere near that fast because an oxy-acetylene torch > > > or plasma cutter can't cut that fast. This rig is most often used for > > > cutting steel 3/4" thick or thicker. > > > > Since counter weights are often used on Z axes on servo machines, I > > once decided to calculate how much of a limit the acceleration due to > > gravity would be. The metric calculations are left for you folks across > > the pond. > > > > Acceleration due to gravity = 16 feet/second/second > > > > Uhh, when I went to school back in rural IA, in 2 feet of snow, uphill 2 > miles both ways, gravity's acceleration was 32 feet per second per second. > Did I go to the wrong school? > > > After 1 second the velocity can be 16 feet per second > > > > times 60 = 960 feet per minute (I love spreadsheets!) > > > > times 12 = 11520 inches per minute > > > > divide that by two, so half of that force can be applied to your cable = > > 5760 inches per minute > > > > HERE'S WHERE I AM MAKING ASSUMPTIONS THAT MAY BE OFF BY A LITTLE. > > > > If I recall properly 1500 inches per minute is a FAST servo system. > > > > 1500/5760 = .26 ( assuming linear acceleration it should only take .26 > > seconds to reach 1500 IPM) > > > > 1500/60 = 25 inches per second > > > > at 25 inches per second that servo system would travel 6.5 inches at > > full speed while the gravity system would be accelerating to 1500 IPM. > > Of course the servo system wouldn't be able to accelerate > > instantaneously, so the counter weight would only slow a 1500 IPM servo > > system down a little bit. > > > > I thought gravity would be much more of a limit too. > > > > ------------------------------------------------------------------------ > > ------ Own the Future-Intel(R) Level Up Game Demo Contest 2013 > > Rise to greatness in Intel's independent game demo contest. Compete > > for recognition, cash, and the chance to get your game on Steam. > > $5K grand prize plus 10 genre and skill prizes. Submit your demo > > by 6/6/13. http://altfarm.mediaplex.com/ad/ck/12124-176961-30367-2 > > _______________________________________________ > > Emc-users mailing list > > [email protected] > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > Cheers, Gene Gene,
But in physics there are often special cases. ;-) My father would, in good weather, ride his 3 speed bike downhill to work and downhill going home. Now, of course this take a bit of explanation: We lived at 1230 ASL. Work was at 920 ASL and when he finished work he rode the elevator to the top of the dam at 1310 ASL and rode home. That (the road) disappeared with the construction of the 3rd powerhouse at Coulee so this special case no longer exists. :-) Dave ------------------------------------------------------------------------------ Own the Future-Intel(R) Level Up Game Demo Contest 2013 Rise to greatness in Intel's independent game demo contest. Compete for recognition, cash, and the chance to get your game on Steam. $5K grand prize plus 10 genre and skill prizes. Submit your demo by 6/6/13. http://altfarm.mediaplex.com/ad/ck/12124-176961-30367-2 _______________________________________________ Emc-users mailing list [email protected] https://lists.sourceforge.net/lists/listinfo/emc-users
