Design Of Intelligent Security System For Elderly People At Home Based On Internet Of Thing

With the advent of the intelligent era,the rapid development of the Internet of Things technology,and the gradual improvement of people’s living standards,smart home has become a hot topic of the era.At the same time,the aging population in China is increasing.However,as the areas where the elderly have the most frequent daily activities,the kitchen and living room are extremely important for the safety of the elderly at home.This article focuses on the issues of current intelligent security systems such as low reliability of gas detection,difficulty in deploying fall detection models,and unstable data transmission from terminal devices.The specific research content is as follows:(1)The detection reliability of traditional gas alarms is generally low,and there is a lack of effective emergency measures to eliminate kitchen gas hazards.This article designs them from both hardware and software aspects.In terms of hardware circuits,the stability of the circuit is improved through operations such as anti surge protection,anti static protection,and filtering processing,while using low temperature drift resistors to enhance the anti-interference of gas detection;In terms of software design,first select limiting average filtering to remove abnormal values from the initial sampling values of the sensor,and then obtain a smooth and stable sampling signal through Kalman filtering and moving average filtering,finally combine linear function conversion to obtain a stable and reliable true combustible gas concentration.In addition,considering the physical inconvenience of the elderly or the fact that they are not at home when going out when there is a gas leak,this article also designs intelligent emergency measures to independently reduce the concentration of gas in the kitchen and ensure the safety of kitchen gas.(2)Due to the low detection accuracy of the lightweight human pose estimation model and the high computational complexity of the fall detection network based on keypoints information,it is not suitable for edge devices.Therefore,this article improves the lightweight model to improve the detection accuracy of the model with less computational complexity.In this paper,a feature enhancement module with low computational complexity is designed at the deepest layer of the original backbone network to effectively establish the relationship between different pixel points in the image,and improve the accuracy of predicting keypoints such as limbs that are away from the geometric center of the human body;In addition,this paper constructs a bidirectional weighted feature pyramid network,which improves the efficiency of feature fusion and increases the accuracy of keypoints location prediction through bidirectional cross scale connectivity and weighted feature fusion mechanisms;At the same time,in order to improve the accuracy of the judgment of falls,this paper designs a judgment standard for multidirectional falls based on the relative position and angle relationship between the coordinates of the keypoints of the human body.Finally,the actual deployment of the model on edge devices is implemented through Open CV.(3)In the intelligent security system for elderly people at home,cumbersome online operations can bring great inconvenience to the elderly.At the same time,mobile apps that need to be downloaded and occupy memory reduce the sense of use experience of guardians.This article selects plug-and-play,safe and stable Internet of Things modules and cloud platforms through comparison,and designs and develops fast and convenient client software based on the mpvue framework.In addition,this article uses the combustible gas detection device in the kitchen and the fall detection device in the living room as nodes to establish a Bluetooth mesh network,and combines the NB-Io T module with the Bluetooth mesh network to design a costeffective gateway controller.Through the Free RTOS operating system,multitasking management is implemented,effectively improving the data transmission efficiency of the gateway and reducing the network operating cost of the system,Realize data communication between each module terminal device and We Chat applet.