From: "Randy" rpratt@.............

Date: Wed, 27 Dec 2006 20:25:26 -0600

Hi Again, Thanks for the earlier replies. I spent a few wonderful days in North = Dakota for the holiday so have just gotten back to it. Bob can you = explain the SeisK in your program? Is it a derived spring constant for = the geometric conditions created or a stability factor? I note that = negative is always unstable but a negative length spring does not create = instability. I still have not answered my original question though. I have 3 = examples from Bob's program below. The first is similar to a spring I = have currently set up. The second is a zero length spring with the same = spring K and attachment point on the boom set to the same period. The = third is a softer spring of 0 length. Given 2 springs and the same = period, will one operate noticably better at a given period in practice? = =20 SpringAngle=3D 25, Force=3D 1.3898, Length=3D 0.2247 X and Y -0.0076,0.1079 TorqueUp=3D -0.000339, Down=3D 0.000337 SeisK=3D 0.6622, Period=3D 1.44=20 SpringAngle=3D 12, Force=3D 2.4595, Length=3D 0.1783 X and Y 0.0216,0.0501 TorqueUp=3D -0.000337, Down=3D 0.000337 SeisK=3D 0.6604, Period=3D 1.44 SpringAngle=3D 35, Force=3D 1.0685, Length=3D 0.1797 X and Y 0.0488,0.1161 TorqueUp=3D -0.000329, Down=3D 0.000329 SeisK=3D 0.6454, Period=3D 1.45Hi Again,Thanks for the earlier replies. I = spent a few=20 wonderful days in North Dakota for the holiday so have just gotten back = to=20 it. Bob can you explain the SeisK in your program? Is it a = derived=20 spring constant for the geometric conditions created or a stability=20 factor? I note that negative is always unstable but a negative = length=20 spring does not create instability.I still have not answered my original = question=20 though. I have 3 examples from Bob's program = below. The=20 first is similar to a spring I have currently set up. The second = is a zero=20 length spring with the same spring K and attachment point on the boom = set to the=20 same period. The third is a softer spring of 0 length. Given = 2=20 springs and the same period, will one operate noticably better at a = given=20 period in practice?SpringAngle=3D 25, Force=3D 1.3898, = Length=3D 0.2247

X=20 and Y -0.0076,0.1079

TorqueUp=3D -0.000339, Down=3D = 0.000337

SeisK=3D=20 0.6622, Period=3D 1.44SpringAngle=3D 12, Force=3D 2.4595, = Length=3D 0.1783

X=20 and Y 0.0216,0.0501

TorqueUp=3D -0.000337, Down=3D = 0.000337

SeisK=3D=20 0.6604, Period=3D 1.44SpringAngle=3D 35, Force=3D 1.0685, = Length=3D 0.1797

X=20 and Y 0.0488,0.1161

TorqueUp=3D -0.000329, Down=3D = 0.000329

SeisK=3D=20 0.6454, Period=3D 1.45Randy