biomechatronics - lecture 7. actuators for mechanical devices

Vermelding onderdeel organisatie

ARTIFICIALMECHANICAL SYSTEMS

for theUPPER EXTREMITY

DICK H. PLETTENBURG

BIOMECHATRONICS WB2432

2007-03-07 STATE OF THE ART IN UE PROSTHETICS

2007-03-14 CONTROL

2007-03-21 ACTUATION

2007-03-07 STATE OF THE ART IN UE PROSTHETICS

2007-03-14 CONTROL

2007-03-21 ACTUATION

Vermelding onderdeel organisatie

ACTUATIONOF

UPPER EXTREMITYPROSTHETICS

PROSTHESESPROSTHESESCONTROL

ALWAYS BY THE BODY

MECHANICAL

ELECTRICAL

POWERFROM THE BODY

EXTERNALLY

BODY POWERBODY POWER

STRAPSSTRAPS

STRAPSSTRAPS

1

2F

F1

R

F2

F2

1F

R

F

STRAPSSTRAPS

STRAPSSTRAPS

STRAPSSTRAPS

ELBOW CONTROLELBOW CONTROL

CLOSING SPRING

HAND OPENS

CONTROLSHELL UPPER ARM

OPERATING CABLE

THUMB HAND CLOSES

ELBOW CONTROLELBOW CONTROL

CINEPLASTY: GIULIANO VANGHETTI 1898CINEPLASTY: GIULIANO VANGHETTI 1898

CINEPLASTY: GIULIANO VANGHETTICINEPLASTY: GIULIANO VANGHETTI

Weir, 1998

CINEPLASTY: FERDINAND SAUERBRUCH 1915CINEPLASTY: FERDINAND SAUERBRUCH 1915

Klopsteg & Wilson, 1954

CINEPLASTY: FERDINAND SAUERBRUCHCINEPLASTY: FERDINAND SAUERBRUCH

Klopsteg & Wilson, 1954

EXTERNAL POWEREXTERNAL POWER

ELECTRICALELECTRICAL

Borchardt et.al., 1919

ELECTRICAL: REITER 1948ELECTRICAL: REITER 1948

Childress & Billock, 1970

ELECTRICALELECTRICAL

Otto Bock

ELECTRICALELECTRICAL

Steeper

ELECTRICALELECTRICAL

DISADVANTAGES:

• HIGH MASS

ELECTRICALELECTRICAL

DISADVANTAGES:

• HIGH MASS

• LOW SPEED

• VULNERABLE

• SIZE

ELECTRICALELECTRICAL

Steeper

HYDRAULICALHYDRAULICAL

ADVANTAGES:

DISADVANTAGES:

• GOOD CONTROL

• FAST

• QUIET

• NO LOCKING DEVICES NEEDED

• HIGH TOTAL MASS

• LEAKAGE

• ENERGY STORAGE

PNEUMATICALPNEUMATICAL

ADVANTAGES:

• LOW MASS

• HIGH SPEED

• RELIABLE

• SMALL

PNEUMATICAL: DALISH 1877PNEUMATICAL: DALISH 1877

Dalish, 1877

PNEUMATICAL: ANONYMOUSPNEUMATICAL: ANONYMOUS

Borchardt et.al., 1919

PNEUMATICAL: HEIDELBERG 1949+PNEUMATICAL: HEIDELBERG 1949+

Lucaccini, 1967

THALIDOMIDE

Issued in 1956 by Chemie Grünenthalto fight nausea and sleeping problems in pregnant women.

PNEUMATICAL: EDINBURGH 1963+PNEUMATICAL: EDINBURGH 1963+

Baumgartner, 1977

PNEUMATICAL: Limb Fitting Centre at Queen Mary's Hospital, Roehampton, London, 1964PNEUMATICAL: Limb Fitting Centre at Queen Mary's Hospital, Roehampton, London, 1964

Steeper, 1964

PNEUMATICALPNEUMATICAL

DISADVANTAGES:

• HIGH OVERALL MASS

• UNRELIABLE

• HIGH GAS CONSUMPTION

• CUMBERSOME REFILL PROCEDURE

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

RE-ASSESSMENT PNEUMATIC ACTUATION:• LIGHT?• FAST?• RELIABLE?• SMALL?

PNEUMATICALPNEUMATICAL

INPUT ENERGY [Nm]

OUTPUT ENERGY [Nm]

EFFICIENCY (%)

WILMER08-06

STEEPERMH 60

OTTO BOCK8K8

0

0.2

0.4

0.6

0.8

1.0

1.2

0

1.2

1.0

0.8

0.6

0.4

0.2

10

20

30

40

50

60

0

1.4

1.4

70

Ereq = 750 Nmm

PNEUMATICALPNEUMATICAL

m = 37.5 g

PNEUMATICALPNEUMATICAL

Ø9.

0

Ø9.

5

12.0

Ø8.

0

10.0

7.9

9.5

Ø6.

0

2.25

2.0

Ø10

.0

m = 1.2 g

PNEUMATICALPNEUMATICAL

• MINIMIZE GAS CONSUMPTION BY

• SYSTEM CHOICE

• REDUCTION OF FRICTION LOSSES

• REDUCTION OF DEAD SPACE

• SUPPLY PRESSURE

• PROTOTYPES

PNEUMATICALPNEUMATICAL

‘BI-PHASIC’ OPERATIONpinching motorpinching spring

closing springprehension motor

locking mechanism

PNEUMATICALPNEUMATICAL

L

d

x max

x

ps

SUPPLY PRESSURE

PNEUMATICALPNEUMATICAL

0

2

4

6

8

10

12

14

16

18

20

0 1 2 3

supply pressure [MPa]ga

s co

nsum

ptio

n [mg]

Ps, opt = 1.2 MPa

Independent of:Δt, L, Fs, and x

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

Δpcontrol

Δpcontrol

patm patm patm

phand mechanism

psupply

I II III IV

p

controlΔp

patm

supply

hand mechanismp

psupply

hand mechanism

atmppatm

p

Δpcontrol

a

b

c

Pneumatic relay:

- Ø 3.5 x 8.15 mm

- ΔP = 0.4 MPa

- Q = 74.2 ltr/hr

- m = 0.66 g

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

Pneumatic switch:

- Ø 3.0 x 4.3 mm

- F = 0.6 N

- Q = 97.0 ltr/hr

- m = 0.19 g

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

Check valve:

- Ø 1.5 x 2.8 mm

- ΔP = 0.48 kPa

- Q ≥ 120.0 ltr/hr

- m = 0.05 g

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

PNEUMATICALPNEUMATICAL

PNEUMATIC ACTUATION EXCELS ELECTRICAL ACTUATION:

• LOW IN MASS• FAST• RELIABLE

• SMALL

McKIBBEN-MUSCLE

Carlson, 1971

McKIBBEN-MUSCLE

Shadow, UK

McKIBBEN-MUSCLE

Univ. of Washington, USA

McKIBBEN-MUSCLE

Shadow, UK

McKIBBEN-MUSCLE

McKIBBEN-MUSCLE

McKIBBEN MUSCLE / PNEUMATIC ARTIFICIAL MUSCLE

KEY ADVANTAGE:

• LOW MASS COMPARED TO MUSCLE STRENGTH

• HIGH FORCE TO WEIGHT RATIO

• HIGH POWER TO WEIGHT RATIO

• ETC.

McKIBBEN-MUSCLE / PNEUMATIC ARTIFICIAL MUSCLE

CLAIMED ADVANTAGES:

• LOW MASS

• HIGH POWER-TO-WEIGHT RATIO

DISADVANTAGES:

• LOW PRESSURE

• UV-SENSITIVE

?

Festo AG

FESTO ADVC-25FESTO MAS-10 FESTO DSN-25

Dsi

DsoDc dido

δx

Dgo Dp Di

Do

1.1ds+0.5

Dgi

1.1ds

WILMER 21xS

PNEUMATIC ARTIFICIAL MUSCLES

Output energy to mass ratio:

( ) ⋅= ∫ F s ds

EtMm

EtM = energy to mass ratio [Nm/kg]F(s) = ouput force as a function of the stroke [N]s = stroke [m]m = muscle mass [kg]

PNEUMATIC ARTIFICIAL MUSCLES

1

10

100

1000

10000

0,001 0,01 0,1 1Stroke [m]

Ener

gy to

Mas

s R

atio

[Nm

/kg]

MAS-10, p = 0.8ADVC-25DSN-25WILMER 21xs, t = 0.25

PNEUMATIC ARTIFICIAL MUSCLES

0

500

1000

1500

2000

2500

3000

Ene

rgy

to M

ass

Rat

io L

imit

[Nm

/kg]

MAS-10 WILMER ADVC-25 DSN-25

PNEUMATIC ARTIFICIAL MUSCLES

Output energy to volume ratio:

( ) ⋅= ∫ F s ds

EtVV

EtV = energy to mass ratio [Nm/kg]F(s) = ouput force as a function of the stroke [N]s = stroke [m]V = muscle volume [m3]

PNEUMATIC ARTIFICIAL MUSCLES

0

0,2

0,4

0,6

0,8

1

1,2

0,001 0,01 0,1 1

Stroke [m]

Ener

gy to

Vol

ume

Rat

io [N

/m2 ]

MAS-10, p = 0.8

ADVC-25

DSN-25

WILMER 21xs, t = 0.25

PNEUMATIC ARTIFICIAL MUSCLES

0

0,2

0,4

0,6

0,8

1

1,2

0,001 0,01 0,1 1

Stroke [m]

Ener

gy to

Vol

ume

Rat

io [N

/m2 ]

MAS-10, p = 0.8

ADVC-25

DSN-25

WILMER 21xs, t = 0.25

0

0.2

0.4

0.6

0.8

1

1.2

Ener

gy to

Vol

ume

Ratio

Li

mit

MAS-10 WILMER ADVC-25 DSN-25

PNEUMATIC ARTIFICIAL MUSCLES

Festo DMSP

Festo MAS

PNEUMATIC ARTIFICIAL MUSCLES

Festo DMSP

Festo MAS

Basic mass difference Δm = 20 g

CONCLUSIONS:

(EtM)PAM > (EtM)Standard Industrial Actuators

(EtV)PAM < (EtV)Standard Industrial Actuators

REDESIGN OF CYLINDER ACTUATORS:

EtM: 5 – 30 x (EtM)PAM

EtV > 3 – 13.5 x (EtV)PAM

DO NOT USE PAM WHERE EtMAND/OR EtV IS CRITICAL

PNEUMATIC ARTIFICIAL MUSCLES

SUMMARYSUMMARY

• CONTROL vs ACTUATION

• BODY POWER

• SHOULDER HARNESS

• ELBOW CONTROL

• EXTERNAL POWER

• ELECTRICAL

• HYDRAULICAL

• PNEUMATICAL

SUMMARY [cont.]SUMMARY [cont.]

• PNEUMATIC ACTUATION EXCELS ELECTRICAL ACTUATION:

• LOW IN MASS• FAST• RELIABLE• SMALL

• DO NOT USE PAM WHERE EtM AND/OR EtV IS CRITICAL

CHALLENGES IN PNEUMATICS:

Miniature and energy efficient pneumatical systems

Research at the Delft Institute of Pneumatics:

• Miniature components

• [Energy efficient] pressure supply

• Miniature servo mechanisms

Pneumatics

- miniature components

Pneumatics

- miniature components

Pressure regulation in the human eye[treatment of glaucoma]

Project in co-operation with

&Rotterdam Eye Hospital

Pneumatics

- supply pressure level

Pneumatics

- exergy saving

Pneumatics

- servo mechanism

[Dario, 2004] [DeLuca, 1978]

[www.icube.co.uk]

[Fraunhofer Institue für Biomedizinische Technik]