19.07.2013 Views

Kinematic and Dynamic Analysis of Spatial Six Degree of Freedom ...

Kinematic and Dynamic Analysis of Spatial Six Degree of Freedom ...

Kinematic and Dynamic Analysis of Spatial Six Degree of Freedom ...

SHOW MORE
SHOW LESS

You also want an ePaper? Increase the reach of your titles

YUMPU automatically turns print PDFs into web optimized ePapers that Google loves.

When we differentiate the equation <strong>of</strong> kinematic energy (5.8) wrt. the angular <strong>and</strong><br />

linear velocity <strong>of</strong> input links <strong>and</strong> impose simple mathematical transformation, we obtain:<br />

∂T<br />

∂w<br />

o<br />

∂T<br />

∂V<br />

i<br />

i+<br />

3<br />

=<br />

=<br />

3<br />

∑<br />

k=<br />

1<br />

3<br />

∑<br />

k=<br />

1<br />

( I w + 0.<br />

5I<br />

V )<br />

k,<br />

i<br />

⎛<br />

⎜<br />

⎜0.<br />

5<br />

⎝<br />

k<br />

o<br />

I k,<br />

i+<br />

3<br />

w<br />

k<br />

k,<br />

i+<br />

3<br />

+<br />

i+<br />

3<br />

o<br />

I k+<br />

3,<br />

i+<br />

3<br />

V<br />

k+<br />

3<br />

⎞<br />

⎟<br />

⎠<br />

(5.10)<br />

Differentiating (5.10) wrt. time <strong>and</strong> substituting those differentiations into Lagrange-<br />

Euler’s equation (5.4) along with equation(5.9) we obtain:<br />

M<br />

r,<br />

i<br />

=<br />

1<br />

3<br />

3<br />

3<br />

3<br />

k , i<br />

k+<br />

3,<br />

i+<br />

3<br />

ε I k , i+<br />

3ai<br />

+ 3 + ∑ wk<br />

wi<br />

− ∑ Vk<br />

+ 3Vi<br />

+ 3<br />

k= 1 2 k=<br />

1 2 k = 1 ∂ϕi<br />

2 k= 1 ∂ϕi<br />

∑Ik, i k + ∑<br />

1<br />

o<br />

o<br />

3<br />

3<br />

1 o<br />

o<br />

3<br />

3<br />

1 ∂ I k + 3,<br />

i+<br />

3 1 ∂ I k,<br />

i<br />

Fr , i+<br />

3 = ∑Ik, i+<br />

3 ε k + ∑Ik+<br />

3,<br />

i+<br />

3 ak<br />

+ 3 + ∑ k+<br />

3Vi+<br />

3 − ∑<br />

2 k= 1<br />

k=<br />

1<br />

2 k= 1 ∂si+<br />

3 2 k = 1 ∂si+<br />

3<br />

∂I<br />

1<br />

∂I<br />

V w w (5.11)<br />

for i = 1,2,3<br />

Equations (5.11) are the equations <strong>of</strong> motion for the 6-DOF manipulator with parallel<br />

structure having variable inertia factors, depending on the input angular <strong>and</strong> linear<br />

displacements <strong>of</strong> six input links.<br />

k<br />

i<br />

60

Hooray! Your file is uploaded and ready to be published.

Saved successfully!

Ooh no, something went wrong!