Design and Development of a Personal Trainer System

Progress Presentation

by

Emer Bussmann

Introduction Exercise is the key to a healthy life importance of personal limits regulate and progress ability to measure, store and track the

progress

The Design of the Proposed System maximum benefit out of training

sessions 1) effective motion sensors for physical

activity assessment 2) Bluetooth-based ECG circuitry 3) low cost portable acquisition system 4) software for monitoring and

processing human body movement

SparkFun Board Bluetooth ECG

sensors

PDA equipped with LabVIEW for data

processing

PC-based Database

Worn by User Bluetooth

LabVIEW8

File Transfer

Fig 3: Block Diagram of system

Accelerometer System

micro-electromechanical device measure acceleration forces (static,

dynamic) change in capacitance antero-posterior, medio-lateral, or

vertical

Solution

WiTilt v2.5 Board from SparkFun Electronics Freescale MMA7260Q triple-axis

accelerometer and a class I Bluetooth link Internal antennae for range

Data acquisition Unit

Acquire and process the signals LabVIEW software to filter, amplify,

rectify and integrate to create clean noiseless output data

Send data to a PC-based database

Solution

Packard iPAQ hw6910/hw6915 Bluetooth type 1.2 and WiFi 802.11b Expansion: mini SD card

Mathematical Basis of the Parameters of Interest

Stride Time Distance Speed Energy expenditure

Stride Time, Distance and hence Speed

vertical bounce (of the hip) in an individual’s step is directly related to the person’s stride length

Step finding algorithm (zero crossing algorithm)

An 8 point moving average is used to search for a maximum peak followed by a minimum

Determine the distance walked

d : distance walked k : constant multiplier max : maximum acceleration value measured in this step min : minimum acceleration value measured in this step avg : average acceleration value for this step accel : represents all measured acceleration values for

the step

completed for each step

Energy expenditure

1) A low pass filter removes the shock noise of moving artefacts,2) Activity x(t) at each axis is determined by integrating the accelerometer signal;

where tau is set to 1s Total activity level is the Vector Magnitude (VM) of the signals; VM = x(t) + y(t) + z(t)3) Every 10s the activity signals were summed

Vertical acceleration the predominant source of signal power

1) Step frequency is estimated using a count of samples between successive zero crossings in the vertical acceleration

2) Another filter is used to remove signals above twice the step frequency

3) VM is averaged at each speed and

4) Gait cycle is normalised to compare signals from different step frequencies

ECG System

maintain a heart rate level that will optimise the effect of physical exercise

use the design of a project from Sweden that is available in the public domain

battery powered measuring up to 3 analogue channels

of ECG on an exercising subject

Amp

Microcontroller

Bluetooth Module

PDAWith LabView

Body Attached Sensors

Analogue Signal

UART SerialConnection Digital Signal

Wireless Fig 7: ECG System

Schematic of ECG system

Progress to date

All of the equipment has been ordered Extensive research Labview8 has been installed on laptop

and currently testing signals from accelerometer

Future work

January:

Construct an ECG monitor February:

Write software to process the accelerometer data

March:

Create a working system

Acknowledgements

I would like to thank my supervisor Professor Gearóid Ó Laighin and PhD researcher Anthony Dalton for all their

help and support.

References

http://www.ncbi.nlm.nih.gov/sites/entrez?cmd=retrieve&db=pubmed&dopt=abstract&list_uids=9216127 … TA accelerometer

http://www.analog.com/UploadedFiles/Application_Notes/47076299220991AN_900.pdf … pedometers using accelerometers

http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/10755/33900/01615295.pdf … energy expenditure and accelerometers

http://ieeexplore.ieee.org/Xplore/login.jsp?url=/iel5/10646/33608/01597820.pdf?arnumber=1597820 … energy expenditure and accelerometers

http://www.brightcity.co.uk/hp_ipaq_6915_pda.htm … PDA

http://www.mobiletechreview.com/HP-iPAQ-hw6915.htm … PDA http://digital.ni.com/public.nsf/allkb/

15987C8CB752EAD786256DC20070B433?OpenDocument … NI for LabVIEW

http://zone.ni.com/devzone/cda/tut/p/id/3260. … NI for LabVIEW http://www.sparkfun.com/commerce/product_info.php?products_id=254 …

Sparkfun

http://forum.sparkfun.com/search.php?mode=results …Sparkfun