David Rogers, Stu Andrzejewski,

sunflowerplateAI and Robotics

Nov 21, 2013 (3 years and 11 months ago)

97 views

David Rogers, Stu
Andrzejewski
,

Kelly Desmond, Brad
Garrod



Receiving correct data


Communicating across network nodes
accurately


Proper operation



EKG graphs

Malicious Nodes


Environmental Factors

Insufficient Node Power


Can destroy…


Health/Lives


Air Pollution


Equipment


Automobile


Environment


Forest Fire





Overall failing sensors can lead to
millions of dollars in damage!

1.
Configure a sensor network

2.
Collect metrics about the network

3.
Create human/network interface

4.
Analyze correlations
between metrics and
node
failure

5.
Validate metrics and test for accuracy

1.
Configure a sensor network

A.
Define network topology

B.
Identify vital components of sensor hardware

C.
Select sensor network hardware

2.
Collect metrics about the network

3.
Create human/network interface

4.
Analyze correlations
between metrics and
node
failure

5.
Validate metrics for accuracy


Mesh
Topology






Nodes communicate directly
to other nodes without the
need of a cluster head



Star Topology






Cluster head
controls data
communication between
nodes



Advantages


Better
performance


Benefits from
centralization


Isolation of
nodes


Simple








Disadvantages


Centralization
dependency


Expensive


Central hub
failure =
network
failure








Advantages


Self
-

healing


Less traffic load


Isolation of
node faults









Disadvantages


Complexity


Installation


Price



What kinds of information
from the sensor

would
be useful to understand how well they are
functioning?


Battery life


Current draw


RF transmission power


Received signal strength


Processor load


Memory utilization



Powercast

P2110
-
EVAL





Features


Low
-
power


Battery
-
free
(RF Power)


Pre
-
loaded
, custom firmware


Temperature
, Humidity, and
Light
Sensors


External
Sensor Port


RSSI
Calculation


USB
interface for power and
data


SunSPOT








Features


Embedded
Development Platform


Extremely
flexible hardware and
software package


Easy
to program
-

Java top to bottom


Connected


Wireless Communication


Mobile & Secure


Built
in Lithium Ion battery charged
through USB


Able
to sense and affect surroundings


Built
-
in
high grade ECC public key
cryptography

1.
Configure a sensor network

2.
Collect metrics about the network

A.
What to monitor?

3.
Create human/network interface

4.
Analyze correlations between
metrics and
node
failure

5.
Validate metrics for accuracy

2A. What to monitor?


External


Humidity


Temperature


Light


Sound


Motion


Pressure


Vibration


Electrical Fields



Internal


Current Draw


Battery Life


Voltage Reported


RF Transmission


Received Signal
Strength


Channel Availability


Processor Load


Memory Utilization
(RAM)

1.
Configure a sensor network

2.
Collect metrics about the network

3.
Create human/network interface

A.
Identify ideal communication protocol

B.
Create graphical user interface

4.
Analyze correlations between
metrics and
node
failure

5.
Validate metrics for accuracy


Must be able to communicate with sensors
remotely


IEEE 802.15.4


Includes
ZigBee
, Bluetooth,
Wifi


Uses CSMA/CA for
secure
communications


Nodes only transmit when
the channel is
idle


Devices
also include power management functions
such as link quality and energy detection
.


Create user
-
friendly display


Handles all incoming data packets from sensor
nodes behind the
scenes


The data will be displayed in a way for easy evaluation
of the sensor data stream and network health


Alerts the operator when failures
have
occurred or
are occurring


1.
Configure a sensor network

2.
Collect metrics about the network

3.
Create human/network interface

4.
Analyze correlations between metrics and
node failure

5.
Validate metrics for accuracy


Determine the most important
metrics
that
identify node
failure


Algorithms for detecting malfunctioning nodes


Majority Voting


Thresholding


Weighted
average


Understanding associations between multiple
metrics


Attempting to measure current draw while the
sensor is transmitting back to the cluster head









1.
Configure a sensor network

2.
Collect metrics about the network

3.
Create human/network interface

4.
Analyze correlations between metrics and
node failure

5.
Validate metrics for accuracy


Design a test plan to ensure a high quality
health diagnostic


Series of controlled experiments


Statistically validate chosen algorithms


Reduce false positives and false negatives


Monitoring s
ensor health is vital for proper
function of a wireless sensor network



Many external and internal factors attribute
to sensor node failure



By designing algorithms and a test plan to
systematically validate failures, important
metrics relating to the health of a wireless
sensor network can be determined