Using Android platform to detect free fall

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 displacement based algorithms. In case a free fall is detected then the user is prompted to respond by touch or voice in order to eliminate any false positives. If there is no response from the user, the system alerts pre-specified contacts by SMS. Our system utilizes commonly used android smart phones without the need of any additional sensors, and hence it provides a feasible and cost effective solution to fall detection.