11_04

Notes_11_04
1 of 20
Three-Dimensional Constraints
General
  0
   0
    q    0
q
t
 q   
   t 
q
   0
    q   q  q   2 q      0
q
q
 q  
q
qt
q
tt
   q q q q  2 q t q    t t 
  0
 q  
  3 q q q q  q q q q q q  3 q t q 3 q t q q q  3 q t t q   t t t 
q
 0
 q 
q
  4 q qq q   3 q qq q  6 q q q q q q    q q q q q q  q 
 
 
 4 q    
 





 4  q t q  12  q t q q q  4   q t q q q  q   6  q t t q  6  q t t
qttt
tttt
q
q
q q q 

Notes_11_04
Scleronomic constraints
independent of time such as mechanical joints
   q q q q 
    q qq q 
      q qq q 
Spherical
SPH  rj P  ri P  03x1
 
 
 
 I 3 
 
 
 
 I 3 
r i SPH
 ' i SPH
p i SPH
r j SPH
 ' j SPH
p j SPH
 A i ~si  'P
 2 A ~s  'P G
i
i
i

  
    
  A j ~sj 'P
 2 A j ~sj 'P G j
SPH  03x1
SPH  Ai ~ i ' ~ i ' si 'P A j ~ j ' ~ j ' s j 'P
using
~ ]'[
~ ]'[
~ ]'[
~ ]'[
~ ]'[
~ ]'[
~ ]'
[H i ]  2[
i
i
i
i
i
i
i
{}SPH  [Ai ][Hi ]{si }'P [A j ][H j ]{s j}'P
Double spherical
2 of 20
Notes_11_04
SPH _ SPH  d ij d ij L2  0
L  cons tan t length
T
for
d   r   r 
P
ij
P
j
 
 
 
 2d ij 
 
 
 
 2d ij 
d   r   r 
P
and
i
3 of 20
ij
P
j
i
T
r i SPH _ SPH
 ' i SPH _ SPH
p i SPH _ SPH
T
 2d ij  A i ~si 'P
T
 4d ij  A i ~si 'P G i 
T
r j SPH _ SPH
 ' j SPH _ SPH
  
 4d  A ~s ' G 
T
 2d ij  A j ~sj 'P
T
p j SPH _ SPH
P
ij
j
j
j
 SPH _ SPH  0
  d  2d  
 SPH _ SPH  2 d ij
T
T
ij
ij
SPH
  d  2d  {}
SPH _ SPH  6 d ij
T
T
ij
ij
SPH
Dot-1
 DOT _1  a i  a j   0
T
for
a i   ri Q  ri P
 
 
 
 01x 3 
 
 
 
 01x 3 
r i DOT _ 1
 ' i DOT _ 1
p i DOT _ 1
r j DOT _ 1
 ' j DOT _ 1
p j DOT _ 1
a  r   r 
Q
and
j
P
j
j
  A ~a  '  a  A ~a  '
 2a ' A  A ~
a  ' G   2a  A ~
a  ' G 
 a j 'T A j
T
i
j
i
i
T
T
j
T
i
j
T
i
i
i
j
i
i
i
  
  
 2a ' A  A ~
a ' G   2a  A ~a ' G 
T
T
 a i 'T A i  A j ~
a j '  a i  A j ~
aj '
 DOT _ 1  0
T
T
i
i
T
j
j
j
i
j
j
j
Notes_11_04
4 of 20
  A ~ '~ '2~ ' A  A ~ '~ '~ 'A  A  a '
 DOT _ 1  a j 'T A j
T
T
T
i
i
i
j
T
j
i
i
j
j
j
i
DOT _ 1  {a j}'T [A j ]T [A i ][ H i ]{a i }'{a i }'T [A i ]T [A j ][ H j ]{a j}'
~ ]'[
~ ]'[
~ ]' )[A ]T [A ][
~ ]'{a }'
 3{a }'T ( [
j
j
j
j
j
i
i
i
~ ]'[
~ ]'[
~ ]' )[A ]T [A ][
~ ]'{a }'
 3{a i }'T ( [
i
i
i
i
j
j
j
Dot-2
 DOT _ 2  a i  d ij  0
T
for
d  r   r 
P
ij
P
j
d  r   r 
P
and
i
ij
 
 
 
 a i 'T A i   a i 
 
 
 
 a i ' T A i   a i 
T
r i DOT _ 2
 ' i DOT _ 2
p i DOT _ 2
P
j
a i   ri Q  ri P
and
i
T
T
 a i 'T ~si 'P d ij A i ~
ai  '


T
 2 a i 'T ~si 'P d ij A i ~
ai ' G i 
T
r j DOT _ 2
 ' j DOT _ 2
T
  
  
 2a ' A  A ~s ' G   2a  A ~s ' G 
T
T
 a i ' T A i  A j ~s j ' P  a i  A j ~s j ' P
T
T
p j DOT _ 2
i
i
T
P
j
j
j
i
P
j
j
j
 DOT _ 2  0
  A ~ 'a 'd  A ~ '~ 'a 'a ' A  
 DOT _ 2  2 d ij
T
T
i
i
i
ij
T
T
i
i
i

i
i
i

~ ]'{a }'3{d }T [A ] [
~ ]'[
~ ]'[
~ ]' {a }'
DOT _ 2  3{dij}T [A i ][
i
i
ij
i
i
i
i
i
 {d ij}T [A i ][ Hi ]{a i }'{a i }'T [A i ]T {}SPH
Euler parameters
EUL  pi  pi 1  0
T
SPH
i
Notes_11_04
 
 
r i EUL
 01x 3 
p i EUL
 2pi 
5 of 20
T
 EUL  0
T
 EUL  2p i  p i 
EUL  6pi  p i 
T
Fixed revolute rotation driver (angle about fixed axis [u v w ]T)
u 
 
angle  about fixed axis û   v 
w 
 

e 0   C 2 
e    
uS
p   1    2 
e 2   vS 2 
e 3  wS  
 2
 e1 
e  e 2 
e 
 3
FRRD    f t   0

1
may use dot products or 2 cos e 0 or 2 sin 1 e12  e 22  e 32
 
 
 
r i FRRD

 01x 3 
 ' i FRRD
 u v w 
p i FRRD
  2 1  e02





2e0 u 2e0 v 2e0 w   2 sin
2e0 u 2e0 v 2e0 w 
2


 FRRD  f t
 FRRD  f tt
 3
FRRD    f ttt
4
alternative
 FRRD    f t   0
 e2  e2  e2
1
2
3

e0

or 2 tan 1 
for
  2 cos 1 e 0
problem for  5    5




Notes_11_04
 
 
 
6 of 20
 01x 3 
r i FRRD
 ' i FRRD
 u v w 
p i FRRD
  2(1  e02 ) 1/ 2 0 0 0


 FRRD  f t
 FRRD  2e 0 e 02 (1  e 02 ) 3 / 2  f tt


3
2
3
FRRD  2 e 0  6 e0 e 0 e0 (1  e02 )3 / 2  6 e0 e 0 (1  e02 )5 / 2  f ttt
alternative
 FRRD    f t   0
for
 
 
 
e3  e 2 
r i FRRD
only for û  1
  2 sin 1 e1
 e 0  e 0
p i FRRD
 0 2e 0
1
T

1
0 0

problem for   175 and   175
 FRRD  f t
 FRRD  2e1 e 12 e 03  f tt
3D relative distance driver (see double spherical)
 3DRDD  d ij d ij f t   0
T
 
 
0
 01x 3 
 ' i FRRD
for
0
d   r   r 
P
ij
q i 3DRDD
q j 3DRDD
f (t)  0
2
j
P
i
and
 
  
 q i
SPH _ SPH
q j SPH _ SPH
3DRDD  2 f f t
 3DRDD   SPH _ SPH  2 f t  2 f f tt
2
d   r   r 
P
ij
j
P
i
Notes_11_04
7 of 20
3DRDD  SP H _ SP H  6 f t f tt  2 f f ttt
Dot-2 distance driver (see dot-2)
 D 2 DD  a i  d ij/ L  f t   0
L  ai  cons tan t length
T
for
d   r   r 
P
ij
j

 

q j D 2 DD
and
d   r   r 
P
ij
j
P
i
a i   ri Q  ri P
and
 
 
q i D 2 DD
P
i
q i DOT _ 2
L
 
q j DOT _ 2
L
 D 2 DD  f t
 DOT _ 2
 D 2 DD 
 f tt
L
DOT _ 2
D 2 DD 
 f ttt
L
General revolute rotation driver
 GRRD    f t   0
Screw distance-angle (see dot-2 and revolute rotation driver)
SDA  a i  d ij/ L     0
L  ai  cons tan t length ,   screw pitch ,   screw angle
T
for
d   r   r 
P
ij
 

 

 

r i SDA
 ' i SDA
p i SDA
j
P
and
i
d   r   r 
P
ij
j
P
i
a i   ri Q  ri P
and
 
r i DOT _ 2
L
 
 ' i DOT _ 2
L
 
p i DOT _ 2
L
 u v w 

   2 1  e 02
2e 0 u 2e0 v 2e0 w

Notes_11_04
Local Joint Definition Frames
local joint definition frame at P
s i ' A  s i ' P C i P s i ' ' A
F ' '  C   A  F 
P T
on i
i
T
i
T ' '  C   T '
P T
on i
i
on i
on i
8 of 20
Notes_11_04
9 of 20
Notes_11_04
10 of 20
Notes_11_04
11 of 20
Notes_11_04
Three-Dimensional Joint Constraints
Revolute
Prismatic
Helical (Screw)
Cylindrical
Universal (Hooke)
Globe (Spherical)
Flat (Planar)
R
P
H(S)
C
U(H)
G(S)
F(P)
Restricts
5
5
5
4
4
3
3
Allows
1
1
1
2
2
3
3
3D mobility
M = 6(nL-1) - 5 nJ1 - 4 nJ2 - 3 nJ3
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Notes_11_04
Spherical S (Globe G)
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Notes_11_04
Double Spherical SS
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Notes_11_04
Universal U (Hooke H)
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Notes_11_04
Revolute R
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Notes_11_04
Cylindrical C
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Notes_11_04
18 of 20
Prismatic P (Translational T)
Notes_11_04
Screw S (Helical H)
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Notes_11_04
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