Surface Acoustic Wave Application for Mechatronics

1
Surface Acoustic Wave Applicationfor Mechatronics

• Masaya Takasaki
• (Saitama University, Japan)
• (PRESTO, Japan Science and Technology
  Corporation, Japan ),

Jun. 24, 2003
2
Masaya Takasaki
1996 B.E. 1998 M.E. 2001 PhD. Precision Eng.,
Univ. of Tokyo Apr., 2001 - Research Associate
Saitama Univ. Dec., 2001 - Member of
Interaction and Intelligence
3
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator - Tactile Display
4
Surface Acoustic Wave (SAW)
Elastic Media LiNbO3
Rayleigh Wave
l 400 mm (_at_10MHz)
5
Properties of Surface Acoustic Wave
SAW a kind of ultrasonic vibration
Fast Response DC - kHz
Simple Structure
Easy Installation
6
SAW Excitation
Interdigital Transducer
7
SAW Reflection
8
SAW Application

• Filters
• Oscillators
• Sensors
• Actuators

9
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator - Tactile Display
10
Gyro Sensor on MEMS Technology

• Structure ?
• Process ?
• Support ?

K. Takemoto et al, Microgyroscope for
Experimental Catheter-type Micromachine, Proc.
Of The Fifth International Micromachine
Symposium.
11
Principle
12
Prototype
13
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor
Linear Actuator - Introduction of SAW Motor -
Miniaturization - Long Stroke - Tactile Display
14
SAW Linear Motor

• Speed gt 1 m/s
• Output Ratio 200300 W/kg
• Precise Positioning lt 20 nm step

• Miniaturized Motor
• Larger Thrust Force
• Long Stroke

15
Comparison of Actuators
16
Principle
17
Configuration
18
Silicon Slider

• ???? mm???1 mm??????
• ?????????

19
10MHz SAW Motor

• Frequency9.6 MHz
• Traverse Speed1.1 m/s
• Thrust Force6.4 N
• Stroke 30 mm

Latest, 8 N
20
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor
Linear Actuator - Introduction of SAW Motor -
Miniaturization - Long Stroke - Tactile Display
21
Miniaturization
Operating Frequency ?

• Transducer Thickness/Width ?
• Area for IDT ?

• Piezoelectric Material Cost ?
• Micro-Actuator

22
Miniaturized SAW Linear Motor
100 MHz
70 MHz
50 MHz
9.6 MHz
23
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor
Linear Actuator - Introduction of SAW Motor -
Miniaturization - Long Stroke - Tactile Display
24
Long Stroke
25

• Self-guidance
• Infinite Stroke
• Precise Positioning

26
Stator Transducer for Long Stroke
27
Long Stroke SAW Linear Motor
Silicon Slider 8 x 145 x 1 mm3
28
Characteristics
Applied Voltage150 V0-p
Traverse Speed160 mm/s ( Pre-load 240
N) Thrust Force23 N( Pre-load 260 N)
Stroke 100 mm
29
Characteristics
Precise Positioning
200 Cycles
12 nm
30
Summary of SAW Linear Motor

• Miniaturization

Frequency70 MHz Traverse Speed 0.6 m/s Thrust
Force23 mN

• Large Thrust Force 8 N(?4mm Slider)

• Long Stroke

Stator Transducer Stroke 100 mm Traverse Speed
160 mm/s Thrust Force23 N Precise Positioning12
nm
31
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator Tactile Display -
Introduction of Tactile Display - Active Type -
Passive Type - Application
32
Tactile Display ?

• Visual Information ? TV, LCD .
• Audio Information ? Speaker, Headphone .
• Tactile Sensation ? Tactile Display

33
Tactile Sensation ?
Haptic Sensation

• Proprioception (Kinesthesia)
• - Sense of Weight, Resistance,
• - Received by Muscles

• Tactile Sensation
• - Sense of Roughness, Friction,
• - Received by Mechanoreceptors

34
Background
Audio Information
Visual Information

Haptic Information

Interaction Between Human and Computer
35
Devices To Indicate Proprioception
36
Purpose

• Proprioception (Kinesthesia)
• - Many Reports
• - Some Productions

• Tactile Sensation
• - Development of Tactile Display
• - Control for Reality

37
Tactile Display Principle
REAL
TACTILE DISPLAY
Mechanoreceptors
Mechanoreceptors
Artificially Generated Mechanical Vibration
Mechanical Vibration according to RUBBING
38
Configuration
39
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator Tactile Display -
Introduction of Tactile Display - Active Type -
Passive Type - Application
40
Standing Wave
41
Principle
SAW on / off Vibration
42
Prototype
Laser Doppler Velocity Meter
Slider
Linear Guide
SAW Substrate
43
Control
f kckrvs
kcconstant 0.00432 - 0.00864
Hz/mm/s krRoughness Information vsRubbin
g Speed mm/s
44
Vibration Measurement Result
Output Signal of A Sensor for Rubbing Speed
Without Control
Controlled
45
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator Tactile Display -
Introduction of Tactile Display - Active Type -
Passive Type - Application
46
Configuration
47
Progressive Wave
SAW Linear Motor
48
Alternative Force
Operators Finger
49
SAW Tactile Display Module
SAW Absorber Heat Sink
IDT
LiNbO3 Substrate
50
SAW Tactile Display Mouse
Pad With Steel Balls
51
Steel Balls
Vibration Measurement
52
Control of Frequency
126 Hz
252 Hz
53
Control of Strength
Duty Ratio 1/16
Duty Ratio 3/16
54
Demonstration
Mouse Cursor
Image of Roughness
Smooth Area
View of PC Screen
55
Outline
- Surface Acoustic Wave (SAW) - Gyro Sensor -
Linear Actuator Tactile Display -
Introduction of Tactile Display - Active Type -
Passive Type - Application
56
Gray-Scaled Image
Distributed Roughness
57
Haptic Expression of Gray Scale


58
(A)
(B)
(C)
(D)
59
Control
r Roughness Information (no dimension) vm
Mouse Speed (p/s) kc Constant
Frequency f kc r vm
r Rough Surface Smooth Surface
60
Evaluation Test

• Shuffle expressed images.
• Rub on whole of the window.
• Guess the displayed image (A-D).

Operators CAN NOT See the image.
Result
?

3
7
(20s, Men)
61
(No Transcript)
62
(No Transcript)
63
Control Engineering Laboratory, Department of
Mechanical Engineering, Faculty of Engineering,
Saitama University Tel [phone] FAX
81-48-856-2577 E-mail masaya_at_mech.saitama-u.ac.
jp