Simulation Analysis of Stewart Platform Safety Mechanism

Hua Chen School of Mechanical Engineering

University of Science and Technology Beijing Beijing, China

chenhua202@126.com

Bailin Fan School of Mechanical Engineering

University of Science and Technology Beijing Beijing, China

fanbailin@sohu.com

Abstract—Safety mechanism, which can move at will when the length of links ranges in its whole extension region, is designed and simulated based on extreme poses. The simulation results indicate that the rotation angle of joints and the distance between two close links satisfy all restrictions when the length of links ranges in its whole extension region. It can be found that the design method about safety mechanism based on links space is a kind of valuable method in mechanism optimization, which transforms the problems about singularity, constraint of the rotation angle limit of joints and links’ interference, into the length constraint of links. And moreover, there is no singular point in the safety mechanism’s whole workspace.

Keywords- Stewart Platform; Safety Mechanism; Simulation

I.

[1~4]

3/6Stewart

Strum[5]

Stewart

II.

A.

[6~8]

1

[9]

Stewart 1

R O

Z

Y

X

r o

zy

x

65

3 2

1

6

42 1

2

p

ppp

p p

b

bb

b

b b

1

3

5

4

1 Stewart

2597978-1-61284-459-6/11/$26.00 ©2011 IEEE

R 1mr 0.75m 1α 100 2α

25 lmin 1m200N 2 3 5 6

1 4

2 3

2

3

2

3

B. 16

[10]

Stewart

[11]

(1)

(2)

1

45 0.1m 16

0.502m0.381m

1

r 0.8m

R 1m

1α 30

2α 100

lmin 1m

III. 1

ADAMSlmax=1.38m 150kg 100kg

ADAMS4

2598

()

()

(m)

(N)

()

()

(m)

(N)

4 ADAMS

°+°− 15~15:xθ , °+°− 15~15:yθ , °+°− 24~24:zθ , x: -0.34m ~ +0.34m, y: -0.33m ~ +0.33m, z: -0.21m ~ +0.21m Z

Stewart

xθ X5 6

(s)

a)

(s)

b)

(s)

c)

(s)

d)

5 )60/2sin(15 tx πθ =

(s)

a)

(s)

b)

(s)

c)

(s)

d)

6 0.34sin(2 / 60)X tπ=

2599

X Y ZZ X Y

2sφ hφ fmin

fmax 20.316.6 79.3N

905.5N

2

sφ ( )

hφ ( )

fmin (N)

fmax (N)

)60/2sin(15 tx πθ = 17.0 5.9 441.1 494.0 )60/2sin(15 ty πθ = 18.1 5.3 436.3 495.0 )60/2sin(24 tz πθ = 20.3 15.8 195.6 690.5 )60/2sin(34.0 tX π= 16.6 16.6 -79.3 905.5 )60/2sin(33.0 tY π= 16.1 16.1 -60.9 890.5 )60/2sin(21.0 tZ π= 5.7 5.7 449.3 496.4

16

3

3 16

sφ ( ) hφ ( ) fmin (N) fmax (N) 1 6.2 6.2 499.0 499.02 24.4 17.5 -144.5 887.63 10.2 22.5 65.8 969.44 32.9 25.9 2.6 947.55 37.3 30.7 -569.5 1024.06 34.6 14.1 395.4 623.57 18.5 12.3 186.2 739.38 30.0 31.5 -291.5 1095.59 25.3 19.4 110.5 757.2

10 44.2 24.0 -298.8 908.411 7.2 18.4 -118.9 864.312 29.0 22.9 -123.3 847.513 31.2 24.9 -136.9 1091.814 30.1 13.4 125.1 639.915 25.0 19.2 20.0 915.816 4.3 4.3 449.3 449.3

1044.2 Stewart10

58 5

38 5

2 3

Stewart

IV.

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