Currently nondestructive testing techniques for composite aircraft structures are disadvantaged when compared to instant structural health monitoring (SHM) systems that monitor the structure while being in-service and give real-time data. This paper reports on the use of Polyvinylidene Fluoride (PVDF) sensors in sensing (or monitoring) and locating the defect of a flexible composite structure. The samples used for the tests were manufactured through the use of vacuum infusion process. The threepoint bending test was performed to determine the material properties. The vertical sample deflection was measured through the use of vertical height Vernier. It should be noted that the samples were analyzed as cantilever beam due to limited availability of test equipment. The sample health was monitored through the use of PVDF sensor. The sensor data was logged and recorded through the use of Fluke-View scopemeter. The 50 g mass pieces were used as a mode of subjecting the structure to the vertical load. The experiment was performed on samples with defects (drilled 3 mm hole) sample and no-defected sample. The deflection and output voltage from the PVDF sensor of all the samples were comparatively studied.

A major manifestation of the Covid-19 virus is acute respiratory syndrome. This brought about the massive need for respiratory support devices. The pandemic caused shortages of these critical devices, such as PEEP valves, which every ventilator must have to make supporting Covid-19 patients possible. PEEP valves are used to create a positive exhalation end pressure to prevent the patient’s lungs from collapsing. This paper presents the developed a CATPUL PEEP valve designed to meet the South African and African continent markets. The CAD model of an AmbuPEEP valve and the CATPUL was designed with SolidWorks and CFD analysis was performed using Simscale software to characterise and compare the results of the two valves. The result of Ambu valve at 2mm valve opening was 1931 Pa pressure and29.74 m/s maximum flow velocity. The CATPUL recorded a maximum pressure of 1937 Pa and 29.77 m/s maximum velocity at the same valve opening. This shows that the designed valve outperformed the one on the market in terms of flow across the valve based on the computational analysis.

Research and development of smart alignment systems is currently being undertaken at the Smart Devices and MEMS Laboratory at the Cape Peninsula University of Technology. The intended devices will harness the remarkable phenomena of shape memory alloys (SMAs), i.e. the shape memory effect and pseudo-elasticity, for actuation purposes. These unique characteristics of shape memory alloy behavior results from an austenitic ⇔ martensitic phase transformation during heating or cooling and/or a de-twinning of the martensitic variants due to an applied load. This paper investigates the microscopic and macroscopic behavior of SMA wires and uses the dynamic one-dimensional thermodynamic and statistical thermodynamic constitutive model proposed by Müller and Achenbach and further refined by Müller and Seelecke in the design of SMA line actuators. This model permits the simulation of the response of a tensile specimen to a thermodynamic input and calculates all phase transformations, phase proportions and deformations as functions of time if the temperature and applied load are prescribed as functions of time. The aim of this research is to develop an understanding of the numerical model and its implementation in the design of SMA line actuators. Specific results should show response time of a given length of SMA wire subjected to an applied load and temperature increase, and the load – displacement relationships for both quasi-plastic and pseudo-elastic behaviors. This paper also introduces some of the devices currently under investigation by the Smart Alignment Systems Research Group.

Shape memory alloy is one of the materials classified as 'smart' materials. Its anomalous behaviour has gained more attention in the field of engineering. There are numerous mathematical models that have been developed to analyze its behaviour. In this paper, a newly developed constitutive model for shape memory alloy is presented. The features of the newly developed model are presented and compared with some of the existing models.