Smart Cane – P14043
Systems Design Review
Lauren Bell, Jessica Davila, Jake Luckman,
William McIntyre, Aaron Vogel
Agenda
• Project Background
• Customer Requirements
• Engineering Requirements
•
•
•
•
•
•
•
Functional Decomposition
Concept Generation [Morph chart and Pugh charts]
Concept Selection
Engineering Analysis
Risk Assessment
Test Plan
Project Plan
Why Design a Smart Cane?
Conventional White Cane
Advantages
Inexpensive and available
Disadvantages
Slow navigation – user must guide
himself/herself
Little/no training
User can “feel” the environment
Guide Animals
Advantages
Disadvantages
Takes commands
Expensive
Detects overhanging and tricky obstacles
Can get sick/hurt
Guides user
Training for animal and user
Long waiting lists
Sometimes not allowed (illegally) in some
situations
User cannot “feel” environment
Ultimate Vision of Smart Cane
Smart Cane
Combined Advantages
Less expensive than guide animal, available, easily replaceable
Little/no training
User can still “feel” the environment
Guides the user (haptic feedback)
Capable of detecting objects not easily felt through conventional cane
Longer range beyond cane tip
Possibility to integrate with other navigation technologies (GPS, stored paths, maps, etc…)
For Our Project…
Our project will focus on these areas:
Smart Cane
Combined Advantages
Less expensive than guide animal, available, easily replaceable
Little/no training
User can still “feel” the environment
Guides the user (haptic feedback)
Capable of detecting objects not easily felt through conventional cane
Longer range beyond cane tip
Possibility to integrate with other navigation technologies (GPS, stored paths, maps, etc…)
Future projects will continue towards final Smart Cane vision…
Customer Requirements
• Since Problem Definition Review
• Emphasis on the haptic handle
• Less emphasis on detection system
• (Make it basic, detect lower-front objects, leave for future projects)
• Future projects:
•
•
•
•
Detection System
Resembles a conventional cane
Operated like conventional cane
Improving battery life, robustness, use in other environments etc…
Engineering Requirements
Revised, concise specs:
• Cane characteristics
• Moment of Inertia
• Spring Constant
• Handle diameter
• Length
Concept Generation
Functional Decomposition
Morph Chart
Cane Structure – Pugh Chart
Plastic
Wood
Aluminum
Fiberglass
Carbon fiber
Low Density
S
S
-
Datum
+
Transmits vibrations/sound
-
+
+
Datum
S
Corrosion Resistant
S
-
S
Datum
S
Low Cost
+
+
-
Datum
-
Ease to work with and modify
+
S
S
Datum
S
Safe for use
S
-
S
Datum
S
+
2
2
1
1
-
1
2
2
1
Concept Selection – Handle*
Attractive/Repulsive Magnetism Navigation
Pros
• Easier to feel direction
• Better directional
feedback
• Can be used with gloves
Screw-in cap
Battery housing
Microcontroller
Cons
• Possible power limitations
• No indication of proximity
(acting alone)
Wire windings
with ferrous
cores
Piston Navigation
Screw-in cap
Pros
• Easier to feel direction
• Better directional feedback
• Can be used with gloves
Cons
• Heavier
• No indication of proximity
(acting alone)
• May inhibit index finger
haptic ability
Standard servo
Battery Housing
Push piston
Drive shaft
Microcontroller
Scroll Navigation
Pros
• Easier to feel direction
• Better directional feedback
• Can be used with gloves
Screw-in cap
Battery Housing
Microcontroller
Continuous servo
Cons
• May inhibit index finger
haptic ability
Scroll
Transmission
Track Ball Navigation
Pros
• Easier to feel direction
• Better directional feedback
• Can be used with gloves
Cons
• Heavier
• Less compact
• May inhibit index finger
haptic ability
Track ball
Screw-in cap
Microcontroller
Battery Housing
Continuous
servos &
transmission
shafts
Torque Handle Navigation
Pros
• Easier to feel direction
• Better directional feedback
• Can be used with gloves
Cons
• Heavier
• Moment of inertia/torque
concern
Screw-in cap
Transmission
Standard servo
Microcontroller
Battery housing
Handle Feedback – Pugh Chart
Handle
Vibration Navigation by Expansion by
Motors
Track ball
Push
Cylinders
Handle
Twist via
Torque
Motors
Ring attached to
Handle
a motors to
Expansion by Thermoelectric
move
Electroactive /Heat in handle finger/Rotating
Polymers
band that slides
across finger
Electromagnets
control finger
direction
Easy to Feel Direction
Datum
+
+
+
+
+
+
+
Provides Directional
Feedback
Datum
+
+
+
+
+
+
+
Safe to use
Datum
S
S
S
S
-
S
S
Compact Design
Datum
-
S
S
-
-
S
S
Lightweight
Datum
-
-
-
-
-
S
S
Affordable within our
budget
Datum
S
S
S
-
S
S
S
Fast Response time
Datum
S
S
S
-
-
S
S
Easy for users to learn
within our time frame
Datum
S
S
S
-
S
S
S
Able to be used with
gloves
Datum
+
+
+
+
-
+
+
Indicates proximity
Datum
S
-
S
-
-
S
S
+
3
3
3
3
2
3
3
-
2
2
1
6
3
0
0
Detection System – Pugh Chart
Ultrasonic
Sensor
Ultrasonic Sensor
Infrared sensor Radar System
w Accelerometer
Image
Processing
Laser
Light Weight
Datum
-
S
S
S
S
Power Consumption
Datum
-
+
S
-
-
Gives good signal for range
Datum
S
-
-
S
S
Sensitive to Objects close/far away
Datum
S
-
-
S
S
Fast Response time
Datum
-
S
S
-
+
Durable
Datum
S
+
-
S
S
Small in size
Datum
S
+
S
S
-
Able to detect all objects
Datum
S
-
-
+
-
Cost
Datum
S
S
S
-
-
Easily Senses object location
Datum
+
-
S
S
-
+
1
3
0
1
0
-
3
3
3
3
4
Engineering Analysis
• Microcontroller
•
•
•
•
Power
Operating Conditions
CPU Speed
I/O Characteristics
• Servo Motors
•
•
•
•
•
•
•
Torque
Weight
Dimensions
RPM
Tolerance/Precision
Power
Continuous/Standard
• Magnets
•
•
•
•
Forces
Weight
Dimensions
Power
• Batteries
•
•
•
•
Heat
Battery Life
Power
Rechargeable vs.
Disposable
• Size
Risk Assessment
Importance
Risk
Likelihood
Severity
6
Burning out micro controller
3
2
6
Software is ineffective
2
3
6
Haptic handle and detection systems integration issues
2
3
6
Not meeting customer expectations
2
3
4
Not obtaining parts on time
2
2
4
Battery malfunction
2
2
4
Over budget
2
2
3
Cane does not stay together, durability failure
1
3
3
Not completing software component
1
3
3
Haptic forces not being strong enough
1
3
3
Hardware and software integration
1
3
3
Detection is ineffective
1
3
3
Uncoordinated team schedules
3
1
3
Team Member leaves team
1
3
3
Cane gets dropped repeatedly on the ground
1
3
3
Excessive tapping
1
3
1
System is too heavy for desired cane weight
1
1
27
43
64
TOTAL
Test Plan
• User Test
• Battery Test
• Physical Characteristics
• Detection System Test
Project Plan
Problem
Definition
• Problem
Statement
• Customer
Requirements
• Engineering
Requirements
System
Design
• Benchmarking
• Functional
Decomposition
• Concept
Generation
• Risk Assessment
• Test Plan
• Engineering
Analysis
• Concept
Selection
Subsystem
Design
Detailed
Design
• Proof of
• Hardware and
Concept
Software Design
• Subsystem
• Updated Risk
Decompositions Assessment
• Subsystem
• Updated Test
Design and
Plan
Analysis
• Updated Test
Plan
• Updated Risk
Assessment
Completed
Design
• Completed
Design
• Assembly
Process
• BOM
• Budget POs
• Test Plan
Three Week Plan
Sunday
9/29
Monday
9/30
Tuesday
10/1
Wednesday
10/2
Thursday
Friday
10/3
10/4
Systems Design Review
Saturday
10/5
Engineering Analysis
10/6
10/7
10/8
10/9
Select Concept
10/10
10/11
10/12
Subsystem Decomposition/Analysis
Engineering Analysis
Proof of Concept
10/13
10/14
10/15
10/16
10/17
10/18
10/19
Subsystem Design
Subsystem Decomposition/ Analysis
10/20
10/21
10/22
Update Test Plan and Risk Assessment
10/23
10/24
10/25
Sub Systems Design Review
Update Test Plan and Risk Assessment
10/26
Questions?
Project Plan