Imagine a home that quietly watches over its residents, recognising when something is wrong without cameras, wearable devices or constant supervision. Researchers at Nottingham Trent University (NTU) have developed a smart monitoring system that could help older adults remain independent for longer while protecting their privacy and providing peace of mind for families and carers.
Developed in collaboration with Integrated System Technologies Ltd, the low-cost system combines radar technology, thermal sensors and smart plugs with artificial intelligence (AI). By monitoring movement, household activities and daily routines, it aims to identify unusual behaviour that could signal a fall, heart attack, stroke or other serious health emergency.
Unlike conventional monitoring systems that rely on cameras or wearable devices, the technology gathers information discreetly. Millimetre-wave radar sensors detect movement throughout the home, while smart plugs connected to everyday appliances track activities such as preparing meals, making tea or working at a desk. Low-resolution thermal sensors recognise whether someone is sitting, standing, walking or lying down without revealing facial features or personal identities.
The system’s AI gradually learns an individual’s normal behaviour patterns, allowing it to recognise unexpected changes. Prolonged inactivity, reduced mobility, disrupted sleep or changes in household routines could indicate an emerging health problem. When a potential emergency is detected, the system can alert family members or care professionals, enabling them to check on the resident remotely or in person.
Dr Yangang Xing, lead researcher from NTU’s School of Architecture, Design and the Built Environment, said the technology responds to the growing desire among older adults to remain in their own homes rather than move into residential care. Beyond detecting emergencies, the system could provide early warnings when someone’s mobility or ability to manage everyday activities begins to decline.
To evaluate the technology, researchers conducted experiments in a simulated home featuring six different room layouts, including bedrooms and living areas with varying furniture arrangements. They recorded a range of everyday activities to assess how accurately the sensors could recognise movement and body posture. The findings showed that combining data from all three technologies improved performance compared with using individual sensors alone.
Dr Geoff Archenhold, chief executive officer of Integrated System Technologies Ltd, believes the innovation could become part of a new generation of intelligent homes that monitor residents’ wellbeing unobtrusively. Such systems could help identify subtle changes in behaviour before they develop into more serious problems, potentially allowing families and healthcare professionals to intervene earlier.
Although further testing in real homes would be needed to establish its effectiveness in everyday conditions, the research offers a promising approach to supporting independent ageing. By combining emergency detection, early health warnings and privacy protection, smart home technology could eventually help older adults remain safely in familiar surroundings for longer. The study, titled Privacy-Preserving Ambient Sensing for Activities of Daily Living: Multimodal Radar-Thermal Human Activity Recognition and Smart Plug Appliance Recognition, was published in the journal Sensors.
More information: Bilal Mohammed et al, Privacy-Preserving Ambient Sensing for Activities of Daily Living: Multimodal Radar–Thermal Human Activity Recognition and Smart Plug Appliance Recognition, Sensors. DOI: 10.3390/s26165066
Journal information: Sensors Provided by Nottingham Trent University