Using Android Platform to detect Free Fall

Abstract:   

            Accidents are often accompanied by a condition of free fall where the person involved needs immediate medical help. In such situations every moment, while alerting appropriate authorities, can be very crucial. This paper presents a detection mechanism for free fall condition using common commercially available electronic devices. We utilize an Android based smart phone with an in-built tri-axial accelerometer for the purpose. Data obtained from accelerometer is analyzed to detect free fall condition using Current fall detection systems generally use one of the following methods for sensing a fall condition: 1. Image recognition 2. Recognition by acoustic/vibration: 3. Worn sensor devices: 4. Recognition by acceleration threshold:In our proposed system the accelerometer inside the Android mobiles is used to detect the fall. This is detected and transmitted via ZIGBEE to the alerting set up which consists of a ZIGBEE module connected to a microcontroller. On receiving the information the microcontroller waits for certain duration of time. If within the time the cancel switch is pressed the microcontroller disregards the received information. If not, a message is generated and sent to the care giver mobile phone.