REAL TIME MONITORING OF POSTURE TO IMPROVE ERGONOMICS

REAL TIME MONITORING OF POSTURE TO IMPROVE ERGONOMICS MANJU GOPINATH 1651310016 PROJECT GUIDE: Mrs. Angeline Kirubha Assistant Professor (Sr. G)

ABSTRACT o To develop a simple posture monitoring system using flex sensor and load cells to improve the posture of a person and to detect the spine stress.

MOTIVATION FOR PROJECT o o o Humanities most frequent complaint 80% of population experiences back pain 98% of back pain patients diagnosed with non specific acute back pain. After a while, poor posture feels normal and regresses further from correct posture. Once poor posture starts to feel normal, it is more difficult to correct.

METHODOLOGY LOAD CELL PC

FLOWCHART LOAD CELL PC

SCOPE OF PROJECT o While dangerous diseases are being combatted on a daily basis, something as simple as good posture is often overlooked and forgotten. o Having proper posture can help eliminate simple back pains as well as chronic cases of disc, nerve and muscle damage.

EXPECTED OUTPUT o o o To design simple, real time posture monitoring system that evaluates posture and gives information about stress on the spine When posture deviates from neutral to bad, alert must be sounded To determine the load acting on the spine for various activities

FLEX SENSOR CIRCUIT

BLOCK DIAGRAM

POWER SOURCE

FLEX SENSOR Given at RA 0

PIC Microcontroller

ADC MODULE o ADC of PIC Microcontroller has 8 inputs for the 40 pin device. o It is a 10 -bit ADC. o +Vref and –Vref is set as VDD and VSS voltages.

LCD

LCD o o VEE determines backlight contrast Data and commands both seny through RS. n o o o Rs high = data, low = command Data Storage through EN R/W is grounded as only writing occurs. Header file lcd. h taken from “Electrosome. com” for programming.

BUZZER

RESULTS

RESULTS

RESULTS

LOAD CELL CIRCUIT

BLOCK DIAGRAM

LOAD CELL o o Strain gauge type load cell. 100 kg rated load cell used. Weight centred by using platform for measurement. Signal from load cell is amplified and sent to PIC microcontroller to be displayed on LCD

LOAD CELL o Bending or applying force causes change in resistance which can be measured by Wheatstone bridge configuration

PIC Microcontroller o o o PIC 16 F 877 A In built ADC Easily programmable Low power, high speed EEPROM technology Programmed to read the load cell variation and to convert and display in Newtons.

PIC Microcontroller

HARDWARE SETUP

RESULTS o FLEX SENSOR n n 2. 2 in with threshold at 45 Forced poor posture for 2 min, dependent on subject discomfort Sensor placement best suited for upper thoracic to mid level For lower thoracic and lumbar regions of spine, flex sensor not capable of detecting the spine curvature adequately

RESULTS o Subjects were chosen of same age group (24 years). Sensor Placement Bend range for posture Buzzer Upper Thoracic > 45 Sounds beyond 45 Lower Thoracic > 42 42 – 45 not sounded Mid Back > 47 Sounds from 45 Lumbar Not detectable No sound

RESULTS o LOAD CELL n n n Strain Gauge load cell with capacity of 100 kg used with input voltage at 5 V. Measurements taken for sitting and standing position with good posture and poor posture conditions. No voluntary movements during measuring period of 30 sec.

RESULTS o LOAD CELL – SITTING n Subjects chosen within same age group (24 yrs) Subject Weight (kg) Load in Good posture (N) Load in Poor posture (N) % increase in load on spine S 1 52 431. 5 433. 2 0. 39 S 2 57 461 464 0. 65 S 3 63 490 492. 6 0. 53

RESULTS o LOAD CELL – STANDING n Subjects chosen within same age group (24 yrs) Subject Weight (kg) Load in Good posture (N) Load in Poor posture (N) % increase in load on spine S 1 52 510 519. 8 1. 92 S 2 57 560 581 3. 75 S 3 63 618 637. 5 3. 15

CONCLUSIONS o FLEX SENSOR n o Flex sensor can be used as a detector for posture applicable to cases of Scoliosis and other Thoracic abnormalities. LOAD CELL n n 85% of body weight is on the buttocks while sitting. Load applied on the body during sitting is less when compared to standing.

CONCLUSIONS o LOAD CELL n In sitting position, poor posture affects the load on spine by 0. 52% increase in load n In standing position, poor posture affects the load on spine by 2. 94% increase in load

WORK REMAINING o o Fine tune the circuitry for errors and changes. Load variation values for subjects with same age and same weight with varying height.

PUBLICATION o Conferences n n o ICAEAS – Tamil Nadu – 20 th March ICETTAS – Kerala – 25 th March Journals n n IJSTE (ISSN 2349 784 X) – 25 th March IJESRT (ISSN 2277 9655) – 12 th April

“Prevention is better than cure” THANK YOU