Analysis of Cartesian Stiffness And Compliance With ... - helix

Model:
Asymmetric Stiffness: Parallel Torsional Springs
B’ 1
s i
F’ P’
B’ i B’ n
W
^
P’
cylindrical
joint
torsional
spring
A 1 l i , k i ,
A i
A n
F
θ i
Hook’s joint
O
• Stiffness matrix is determined in closed form.
• Skew-symmetric part is not a simple function of the applied wrench.
• Symmetry theorem does not apply.
• If all springs are unextended then
^
^ ^
K = Σ k i S i S i
T
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