Significant research efforts have been directed into smart home environments in the last decade creating abundant opportunities for the broader home services ecosystem to foster a wide range of innovative services. Research interest has been given on automatic identification and tracking of people within the home environment to support customised services such as care services for elderly and disadvantaged people to enable and prolong their independent living. Although various approaches have been proposed to tackle this problem, solutions still remain elusive due to various reasons (e.g. user acceptance). Literature reviews have indicated the need for an advanced non-tagged identification and tracking approach that is capable to provide the infrastructure support for realisation of context-aware services, satisfy users’ needs, and deal with the complexity of smart home environmental conditions. The aim of this study is to develop and implement an advanced approach that is capable to accurately detect, identify, and track people within opportune and calm home environment to be used as infrastructure for various application domains such as assisted living, healthcare, security and energy management. Accordingly, a novel multimodal approach for non-tagged human identification and tracking within home environment is proposed. The proposed approach combined floor pressure and PIR sensors through unique designed integration strategy aiming to merge the advantages of the two sensor types and overcome or minimise their weaknesses. The designed strategy enabled the PIR output signal pattern to afford explicit information indicating a person’s body surface area (size/shape). This information enhanced the identification accuracy, facilitated the custom designed smart floor, and reduced the overall cost. The conceptual framework of the proposed approach/strategy encompassed two key stages, hardware system design and implementation, and data processing. The hardware system design included the custom designed PIR and smart floor units. A test bed was designed and implemented for supporting the research studies, including proof of concept, concept demonstration, experimental and test cases studies. Data processing system has divided into different stages to accomplish the identification and tracking goals. First, the interested patterns were segmented and generated with threshold edge detection method and advanced pattern generation algorithm respectively. Second, limited set of features were extracted and selected from each pattern including ground reaction force GRF, gait, and body size/shape (PIR) features. Third, these features were merged at different fusion level, namely, feature-level and decision-level to provide comprehensive description about the person’s identity. Fourth, MLPNN multiclass classifier was adopted to process the feature vectors and recognise the person’s identity. Finally, the footstep patterns were tracked using weighted centroid tracking technique, in addition to MLPNN classifier to handle the footsteps association problems. Four test cases were designed and carried out to demonstrate, test, and evaluate the feasibility and effectiveness of the proposed non-tagged identification and tracking strategies/approach. The assessment outcomes have shown the potential of the proposed multimodal approach as an advanced strategy for implementation of an indoor non-tagged human identification and tracking system and to be used as infrastructure for supporting the delivery of various types of smart services within the smart home environments. In summary, the proposed multimodal approach has the potential to: (1) Identify up to 5 persons successfully with minimum 98.8% correct classification rate without tag, (2) detect, locate, and track multiple persons successfully without tag and the location error no more than 11.76 cm, approximately 1.5 times better in accuracy than the original set target (i.e. 30 cm), and (3) able to handle various tracking difficulties and solve 97.5% of data association problems.

In this thesis, the results pertaining to various investigations carried out on Triglycine sulphate (TGS) single crystals, polyvinylidene fluoride (PVDF) films, lithium tantalate (LT)/PVDF nanocomposites and LT thin films are presented with emphasis on the characteristics that are crucial for their use in pyroelectric sensors. TGS single crystals (size 68 x 45 x 42 mm3), which have high pyroelectric coefficients, were grown by slow cooling method using newly designed platform technique based crystal growth work stations. The problem of slow growth rate along c-direction was overcome by placing (010) oriented seeds on the platform. The grown TGS crystals were used for the fabrication of the laser energy meter and temperature sensor. One drawback of TGS is its low Curie temperature (490C). As a consequence when the operating temperature approaches the Curie temperature, the crystals start depolarizing owing to the movement of domains. As a result the linearity of the devices gets affected and restricts the use of TGS. Therefore pyroelectric materials possessing higher Curie temperatures and larger pyroelectric coefficients than that of TGS are desirable. LT in single crystalline form having Curie temperature of ≈6000C has already been in use for pyroelectric device applications. However, growing stoichiometric LT single crystal is very difficult. On the other hand PVDF polymer films (Tc≈1800C) have low pyrolectric coefficients and difficult to pole electrically. Therefore efforts were made to prepare LT/PVDF nanocrystal composites to increase the pyroelectric coefficient of PVDF and to reduce the poling field. Nanoparticles of LT were prepared using sol-gel route. Spherical nanoparticles of size 20-40nm were prepared from sol by adding oleic acid to it. These nanoparticles were characterized using XRD, TEM, DSC and Raman spectroscopy. PVDF films with large percentage of β-phase (ferroelectric phase) were fabricated from solutions prepared using dimethylsulphoxide (DMSO) solvent. PVDF films (30µm thick), embedded with 20-40nm sized nanocrystallites of LT were fabricated to utilize them for pyroelectric sensor applications. The ferroelectric and pyrolectric properties of nano composite films were studied for sensor applications point of view. As a replacement for the single crystals of LT in pyroelectric sensors, investigations were carried out on oriented LT thin films. The studies on LT thin films yielded promising results which could be exploited for pyroelectric sensor applications.