Purpose The purpose of this paper is to present the development of a cost-effective acrylonitrile butadiene styrene (ABS)-rice straw (RS) composite filament for use in fused deposition modelling (FDM) and the effect of RS content on the mechanical properties of the developed filament. Design/methodology/approach RS and ABS were processed and mixed at varying fibre content (5-15 per cent). Filament using each mixture was produced using a single screw extruder. Tensile, flexural and water absorption specimens were prepared using a FDM machine. The mechanical properties were then tested following ASTM standards. Scanning electron microscope images of the specimens were also taken. Findings Tensile properties decreased as the RS content increased. However, specimens with a 0° raster angle showed better tensile properties than the 45° raster angle specimens, indicating that tensile properties of FDM parts are anisotropic. Flexural properties decreased as fibre content increased but increased at 15 per cent fibre content. Water absorption of the composite increased as the fibre content increased. Originality/value This paper highlights a new method of disposing of rice straw waste, by producing an ABS-RS filament for FDM. The resultant filament is cost-effective and can be used to produce cheap prototypes. This paper is the first that studies ABS-RS composites in FDM.

The importance of the brake-by-wire (BBW) system emerged from the fact that it replaces all the conventional hydraulic braking system components with electronic signals between sensors, control modules, and electrically driven braking actuators. This conversion has enormously contributed to the braking system performance in terms of responsiveness, integration with other vehicle subsystems, and an adaptive behavior in different driving circumstances. The aim of this research is investigating the sliding mode control (SMC) strategy to a proposed BBW system. To achieve this aim, BBW system is modeled and validated experimentally. The SMC strategy is applied to the model and validated experimentally. Moreover, this research focuses on compensating for the effect of worn pads on braking performance. The experimental work shows that the developed system model gives matched results with the experimental work. Applying SMC to the model shows a good performance in breaking operation with acceptable error. Applying of the SMC to the test rig shows a good performance with acceptable deviations. In addition, the experiments show that the control strategy is able to compensate the wear in braking pads and keep tracking the braking command.

In light of the scarcity of design data for arthroscopic surgery equipment due to manufacturers’ non-disclosure of research and patents, the aim of the presented work is to study the mechanical stresses experienced by the arthroscopic shaver during soft tissue resection, thus reaching a new design that enhances performance and tool life. The finite element analysis method was used to determine the effect of changing either the tooth angle or rotational speed on stresses experienced by the shaver by creating a model on ANSYS Explicit Dynamics Module. Results were analysed to find that a tooth angle in the range of 55° to 62° would achieve less stresses on the blades, as well as verifying that cutting at 1500 rpm is the most suitable speed for a longer tool life. This research is a part of a project implemented by the NRC and is planned to be verified by experimental work.

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