Wireless Body Area Networks for Wearable Robotics and Human-Robot Interaction

ZHANG Guanglie

Dept. Mechanical and Biomedical Engineering City University of Hong Kong

glzhang@outlook.com

Wireless Body Area Networks

Different miniaturized, low power sensor nodes are attached or implanted into a human body to collect the physiological parameters and transfer data to a remote server or networks.

Personal Server

Wearable Computing

• Study or practice of inventing, designing, building,

or using miniature body-borne computational and

sensory devices.

Wearable computers may be worn under, over, or in clothing, or may also be themselves clothes (i.e. "Smart Clothing" (Mann, 1996a)). Mann, Steve (1996a): Smart Clothing: The Shift to Wearable Computing. In Communications of the ACM, 39 (8) pp. 23-24

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History of Wearable Computing

Made with beads of a silver ring abacus of 1.2 centimeter long and 0.7 centimeter wide, dating back to Chinese Qing Dynasty (1616-1911 BC).

The portrait was painted in around 1560, The first watches appeared shortly after 1500 in Germany and horologists believe the picture, painted by renaissance master Maso da San Friano around 1560 (http://news.bbc.co.uk)

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http://www.interaction-design.org

Now and Future of Wearable Computing

Microsoft Hololens.

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Wearable Robotics

• Powered exoskeleton

Intelligently powered exoskeleton

bionic devices can be strapped on

human body to enhance the

strength, mobility, and endurance

of soldiers and disabled people.

http://harvardmagazine.com/2014/01/wearable-robots

Human-Robot Interaction

"Human—Robot Interaction (HRI)

is a field of study dedicated to

understanding, designing, and

evaluating robotic systems for use by or with humans

"(Goodrich and Schultz, 2007, p.

204).

The ExoHand enables remote object manipulation.

http://machinedesign.com/robotics/pneumatics-provide-grip-new-bionic-hand

Wired or Wireless ?

Challenges for Wireless Body Area Networks

• Development platform: complex and time-

consuming - Cooperative Software-hardware

Approach

• Communication: high energy consumption and low

throughput - Variable-rate Transmission Method

• Security: low security level and computational

complexity - Convolutional Neural Network based

Personal authentication

Application

Component

Application

Configuration

Routing

Component

Routing

Configuration

MAC

Component

MAC

Configuration

Embedded Operating System

Application

Module

Routing Module

MAC Module

WBAN Simulator

Code Generator

Begin

Preprocess

Process 1

Process n

End

Cooperative Software-hardware Platform

Hardware parameters

Variable-rate Transmission with Coordinator Election

1 2

3 4

N1

1

3 4

2N2

(a)

(c)

N1

N2

(b)

2

N2 > N1

N4 < N1

1

43

N3 < N1

1 2

3 4

N1 < N2

(d)

Coordinator

Non-Coordinator

Interval: N2>N1>N3>N4

Variable-rate Transmission Protocols

• Cycle structure

CEP ATSAP DTP

CYCLE 1

SP DTP

CYCLE n

Frame 1 Frame 2 Frame 3 Frame n

...

Frame 1 Frame 2 Frame 3 Frame n

...

CEP: Coordinator Election Peroid ATSAP: Adaptive Time Slots Allocation Peroid

DTP: Data Transmission Peroid SP: Synchronization Peroid

Time slot

Variable-rate Transmission Method Performance

• Electrocardiogram (ECG)

Features:

chaos, university,

permanence,

uniqueness, robustness

and liveness detection

Biometric Personal Authentication

0 300 600 900 1200 1500

-1.0

-0.5

0.0

0.5

1.0

1.5

ECG-based Personal Authentication Architecture

Convolution Fully Connected

Subsampling

Layer

Subsampling

Layer

Convolutional

Layer

Convolutional

Layer

Fully Connected

Layers

Input

Convolutional Neural Network Structure

0.4 0.6 0.8 1.0 1.2 1.4 1.6 1.8

-0.1

0.0

0.1

0.2

0.3

0.4

0.5

0.6

0.7

0.8

Fal

se A

ccep

t R

ate

(FA

R)

(%)

Threshold

FAR

0

20

40

60

80

100

FRR

Fal

se R

ejec

t R

ate

(FR

R)

(%)

1.35

• Dedicated ECG collecting hardware platform

CNN-based Personal Authentication

error rate (EER) of 0.5%

The results of the verification experiment shows the equal error rate (EER)

reaches 0.5%.

Conclusions

• Wireless technology is used in Wearable Robotics

and Human-robot interaction based WBANs;

• Cooperative Software-hardware Platform;

• Variable-rate transmission method with coordinator

election;

• ECG-based personal authentication for data

security and privacy in wireless body area networks.

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Thanks！

6/30/2015 19