This paper presents an approach that adopts the use of computer technology, vibration sensor, and signal processing theory for the condition monitoring of rotating machinery. In this work, a virtual instrument based on LabVIEW was developed to acquires and analyses vibrations of a test rig of rotating machinery. The test rig consists of an AC induction motor, a pulley-belt system and a shaftrotor system that were assembled. Vibrations of the test rig are measured by using micro-electro-mechanical system (MEMS)-based accelerometers. The measured vibrations are acquired in the time domain and are analyzed in the frequency domain by using the developed virtual instrument. In general results of this experiment are shown that the developed virtual instrument able to acquires and analyses the vibrations of the test rig.

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The process of mixing the spices often done manually, which it takes time and reduces the effectiveness of the process. This study aims to analyze the design, material requirements and production process of a spices mixer machine. In this work is also done to analyze the speed optimization in mixing process of spices with the main food. Analysis of the machine design using the finite element method by aided Autodesk Inventor software. The analysis results show that the mass density of the frame is 8.8041 g/cm3, and the maximum compressive strength is 345 MPa. Furthermore, the young’s modulus is 200 GPa, the position ratio is 0.3 and the shear modulus is 76.9231 GPa. The test of spices mixer machine showed that the optimal spice stirring value occurred at 35 rpm with a mixing percentage of 83%.

In this study, the design of a wind tunnel was carried out to observe airflow through an airfoil, streamlines and turbine blades. To accommodate this, in this study a design was made of an open return wind tunnel. In this case, an open circuit wind tunnel type will be made because the construction is simpler and the manufacturing costs are relatively cheaper compared to the closed circuit wind tunnel type. The Wind Tunnel is designed with Open CLosed Wind Tunnel (OCWT) type. The OCWT is designed to consist of fan and housing, diffuser, test section, contraction, honeycomb. The OCWT design uses an operating fan to circulate air into the test section. The maximum air speed in the Test Section is 5 m/s with a flow that is closed to laminar. The recommended diffuser has a dimension of 50 cm on the side that is attached to the test section and 52 cm on the side facing the fan with an inclination angle of 1.79o. The driver uses a 16 inch exhaust fan with a power of 74 W to make the flow in the Test Section stable at a speed of 2 m/s.

The purpose of this study was to analyze the effectiveness of the hardening-temper process on the strength of M8 bolts. The research was carried out through a hardening process with heating temperatures of  900°C, 1000°C, 1100°C, using a holding time of 15 minutes then quenched in aquadest cooling medium, then continued with a tempering process at the same tempering temperature of 400°C followed by cooling at room temperature. The torsional strength of the M8 bolt was obtained through torsional testing using the SM 1 MK II Torque Testing Machine. The results showed that the torsional strength of treated M8 bolts was lower than without treatment. Efforts to increase the torsional strength of M8 bolts with the hardening – tempering method are not recommended, because M8 bolts are made of low carbon steel which has low hardenability, so that the increase in torsional strength of M8 bolts is not significant.