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					           INTERNATIONAL and Communication Engineering & Technology (IJECET),
  International Journal of Electronics JOURNAL OF ELECTRONICS AND
  ISSN 0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), ©

ISSN 0976 – 6464(Print)
ISSN 0976 – 6472(Online)
Volume 3, Issue 2, July- September (2012), pp. 41-47
Journal Impact Factor (2011): 0.8500 (Calculated by GISI)

                           Vani. Surapaneni#1, V. Shanthi Sri#2
                             ECE Department, JNTU Kakinada
                      VRS & YRN College of Engineering & Technology,
                          Cherala. Andhra Pradesh (State), India.

  This paper describes system for monitoring and fall detection of patients using triaxial
  accelerometer together with ZigBee transceiver to detect fall of patients. The system is
  composed of data acquisition, fall detection and database for analysis. Triaxial
  accelerometer is used for human position traking and fall detection. The system is capable
  of monitoring patients in real time and on the basis of results another important parameters
  of patient can be deducted: the quality of therapy, the time spent on different activities, the
  joint movement, etc. The system, including calibration of accelerometers and measurement
  is explained in detail.
     The Accidental Fall Detection System will be able to assist carers as well as the elderly,
  as the carers will be notified immediately to the intended person. This fall detection system
  is designed to detect the accidental fall of the elderly and alert the carers or their loved ones
  via Smart-Messaging Services (SMS) immediately.
    This fall detection is created using microcontroller technology as the heart of the system,
  the accelerometer as to detect the sudden movement or fall and the Global System for
  Mobile (GSM) modem, to send out SMS to the receiver.

  Keywords-component; accelerometers, fall detection, ZigBee standard

  The leading health problems in the elderly community. They can occur in home as well as
  in hospitals or in the long-term care institutions [1]. Falls increase risk for serious injuries,
  chronic pain, long-term disability, and loss of independence, psychological and social
  limitations due to institutionalization. Nearly 50% of older adults hospitalized for fall-
  related injuries are discharged to nursing homes or long-term care facilities [2]. A fall can
  cause psychological damage even if the person did not suffer a physical injury. Those

International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

who fall often experience decrease activities of daily living and self-care due to fear of
falling again. This behavior decreases their mobility, balance and fitness and leads to
reduced social interactions and increased depression. The mortality rate for falls increases
progressively with age. Falls caused 57% of deaths due to injuries among females and 36%
f deaths among males, age 65 and older [3]. Majority of falls result from an interaction
between multiple long-term and short-term factors in person’s environment [4].
  Common risk factors include problems with balance and stability, arthritis, muscle
weakness, multiple medications therapy, depressive symptoms, cardiac disorders, stroke,
impairment in cognition and vision [5,6].Detection of a fall possibly leading to injury in
timely manner is crucial for providing adequate medical response and care. Present fall
detection systems can be categorized [7,8,9] under one of the following groups:
  • user activated alarm systems (wireless tags),
  • floor vibration-based fall detection,
  • wearable sensors (contact sensors and switches, sensors for heart rate and temperature
  accelerometers, gyroscopes),
  • acoustic fall detection,
  • visual fall detection.

The most common method for fall detection is using a triaxial accelerometers or bi-axial
gyroscopes. Accelerometer is a device for measuring acceleration, but is also used to detect
free fall and shock, movement, speed and vibration. Using the threshold algorithms while
measuring changes in acceleration in each direction, it is possible do detect falls with very
high accuracy [11]. Using two or more tri-axial accelerometers and combining them with
gyroscopes at different body locations it is possible to recognize several kinds of postures
(sitting, standing, etc.) and movements, thereby detecting falls with much better accuracy

An easy and simple method to detect fall detection of patients is using accelerometer
together with ZigBee transceiver to communicate with Monitoring System through
wireless network, and in this paper a system for monitoring and fall detection of patients
using mobile MEMS accelerometers will be presented.

  The whole system consists of a set of sensors (two or more sensors on the patient,
usually MEMS sensors) which the patient wears on himself, local units to collect data that
are placed in patient vicinity and systems for collecting.
  The tiny sensors in the strap are capable of measuring user orientation and motion in
three-dimensions and it is constantly monitoring and analyzing the signals in real-time
looking for movement indicating a fall.

International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

                                Figure 1: myHalo System Flow


                                                 Total Cost Approximate       in
   Systems      Installation                     per Annum SGD
                                                 (USD)      (USD 1 = SGD 1.4)

                Self ,
   Alert1       “plug-n-play”       USD 27.95      335.40          469.60
                and pendant
   myHalo                        USD 59.00       708.00      991.20
              Chest strap
   Table Error! No text of specified style in document..1 Comparison of Elderly Fall
                                   Detection System
       From the comparison Table Error! No text of specified style in document..1, it
shows that the system maybe a hindrance to the consumer in terms of price over the years.
The aim of this project is to be able to provide equal standard of care at an affordable cost.

        The system is shown in Figure 1 The space is divided into sections which are
defined by interior and exterior of the institution in which a system is operated. Each room
is stocked with local receivers. Local receivers collect data from sensors that the patients
are wearing on the clothes. The sensors are small and lightweight.

         One sensor is located in the upper garment and the other at the bottom. This is not
limited to two sensors, if necessary, there may be more, but for the detection of falls to the
back the system must have at least 2 sensors [13]. Local receivers pass information to the
server. The server information is processed local health care service. Personal computers
are used to browse the database collected at the server. The database contains information
about the mobility of patients, treatment efficacy, joints. All these data can be analyzed
offline and used to adjust patient therapy. This has served a double function of the system:

International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

real-time patient monitoring and early detection of the fall in order to deliver medical
assistance as soon as possible.

                     Figure 2. System for monitoring and fall detection

  In this application FreescaleTM ZSTAR wireless sensing triple axis board is used (Fig.
2). It is very practical because of low power consumption, portability, and the ability to be
mounted in small pockets inside the clothes of patients. Board is divided into sensory and
receiver part. The sensor is placed at the patient and is equipped with an accelerometer,
microprocessor, and transceiver with the antenna which sends the measurement data to the
receiver. The receiver also has a microprocessor that adjusts the signals received through
the antenna to send with the USB protocol.
  These data are sent to the server. The server collects, process and stores the data. Each
sensor that is connected to the patient is personalized, and its data are stored in a file under
person's name to get an overview of all activities and physical stress of the patient

                  Figure 3. Wireless ZSTAR accelerometer sensing board


  In this chapter the operation of the system through one of its functions and to the
detection of fall will be described. The figures have been simplified for better

International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

understanding of the system. The algorithm used is improved algorithm given in [13], with
better detection of backwards falls. Setup for accelerometer fall detection (Fig. 3.), consists
of the measuring sensors with transmitter, receiver and server for data processing and fall

                        Figure 4 Accelerometer fall detection system

  The fall is detected by the algorithm described in Figure 4. It can be seen that fall
detection algorithm uses data from both sensors that are monitored at the same time.

  This algorithm is able to distinguish between falls( forward ,back word fall into a sitting
position) and the normal daily activity, such as walking, mastering stairs, sitting in a chair,
lying walking is also detecting by the sensors.

               Figure 5 Algorithm for fall detection with two accelerometers
International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

        However, these impacts are not isolated, and after them there is no significant
change in orientation between the two sensors. Vectors are in the area that will call
common zone .if an isolated stoke which causes a change in orientation of the body is
detected, or the orientation of certain body parts in relation to the situation before the
stroke, then with some certainty it can be said that the fall hade occurred.

  This reference design is intended to be a hardware and software platform that enables
evaluation of our ZigBee transceiver MC13192, 3-axis accelerometer MMA7260Q, and the
MC56F8013 Digital Signal Controller.
  This section describes in more detail the electrical design of the module, its features and
the advantages of using a hardware architecture like the one proposed in this reference
  Figure 6 presents the block diagram for the hardware module of the reference design. As
can be seen, the design is centered around the processing unit (the MC56F8013 DSC).
Some peripherals were added to enable user interaction, such as the buzzer, the push
buttons, and the LEDs. A JTAG interface was added for programming and debugging. For
additional debugging and to allow for serial communication, a serial interface was
included. The board is powered either from a 9 V battery or from an external 9 V power
supply. The voltage regulator provides 3.3 V. The RF Transceiver is controlled by the
DSC, and accomplishes transmission and reception of data packets using the PCB dipole
antennas. The antennas connect to the transceiver using matching networks.
  The design is simple, yet it has the necessary elements to evaluate many applications,
thus reducing development time and costs.

                           Figure 6 Human fall detection building block

Triaxial accelerometers can be used for detecting fall of patients. They offer low cost solution, and
together with wireless connectivity solutions such as ZigBee provide efficient solution for both
patients and medical personne l. This paper describes the system for monitoring and fall detection
International Journal of Electronics and Communication Engineering & Technology (IJECET), ISSN
0976 – 6464(Print), ISSN 0976 – 6472(Online) Volume 3, Issue 2, July-September (2012), © IAEME

of patient using triaxial accelerometers sensors. The system parts are shown and described. The use
of two accelerometers on patient’s body as explained in this paper can be used to detect falls. And
all data that is collected about a patient are stored in.


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Subhas Chandra (ur.). Berlin : Springer-Verlag, 2010.pp: 259-275.the database on the server and
can be used to improve health care for the patient.

Vani. Surapanannnei has completed my B.Tech (EIE) from ST. Anna’s College of Engineering &
Technology, Cherala. Presently pursuing M.Tech (VLSI & ES) from VRS & YRN College of
Engineering, Cherala, Andhra Pradesh.


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