Ma Lei, Li Xingguang, Liu Guoxiang, Cai Yujian
School of Electronic Information Engineering, Changchun University of Science and Technology, Changchun 130022, China.
Sensors (Basel). 2023 May 24;23(11):5031. doi: 10.3390/s23115031.
Accurately detecting falls and providing clear directions for the fall can greatly assist medical staff in promptly developing rescue plans and reducing secondary injuries during transportation to the hospital. In order to facilitate portability and protect people's privacy, this paper presents a novel method for detecting fall direction during motion using the FMCW radar. We analyze the fall direction in motion based on the correlation between different motion states. The range-time (RT) features and Doppler-time (DT) features of the person from the motion state to the fallen state were obtained by using the FMCW radar. We analyzed the different features of the two states and used a two-branch convolutional neural network (CNN) to detect the falling direction of the person. In order to improve the reliability of the model, this paper presents a pattern feature extraction (PFE) algorithm that effectively eliminates noise and outliers in RT maps and DT maps. The experimental results show that the method proposed in this paper has an identification accuracy of 96.27% for different falling directions, which can accurately identify the falling direction and improve the efficiency of rescue.
准确检测跌倒并为跌倒提供清晰的方向,能够极大地帮助医护人员迅速制定救援计划,并减少送往医院途中的二次伤害。为了便于携带并保护人们的隐私,本文提出了一种利用调频连续波(FMCW)雷达在运动过程中检测跌倒方向的新方法。我们基于不同运动状态之间的相关性来分析运动中的跌倒方向。利用FMCW雷达获取了人从运动状态到跌倒状态的距离-时间(RT)特征和多普勒-时间(DT)特征。我们分析了这两种状态的不同特征,并使用双分支卷积神经网络(CNN)来检测人的跌倒方向。为了提高模型的可靠性,本文提出了一种模式特征提取(PFE)算法,该算法能有效消除RT图和DT图中的噪声和异常值。实验结果表明,本文提出的方法对不同跌倒方向的识别准确率为96.27%,能够准确识别跌倒方向并提高救援效率。