Journal of Majlesi Journal of Mechatronic Systems
Volume:3 Issue: 3, Sep 2015

In this paper we want to review total structure of adjoining robots and will represent a solution for direct and adverse kinematics by geometric analysis also acquires all the parameters. Then with representing offering direction by using adverse kinematics, we are going to simulate it for both one and three portion of robots and compare this hypothetical direction with actual model. Finally, the end part devotes to comparison and influences of main parameters to gether ans their role in controlling and determining the direction of adjoining robot.

Rising energy prices and growing energy technologies are encouraging consumers and governments to investment in renewable energy sources. Biogas is a kind of these renewable energies sources which have been considered in electrical energy generation. Biogas can be obtained of different natural wastes like municipal sewages, animal wastes, agricultural wastes and industrial wastes. So biogas recovery systems can be established in all places where can access to mentioned resources. This shows simplicity, abundance and accessibility of this type of energy generation. This paper has focused on different parts of power generation from biogas-municipal wastewater system and has been introduced some important and simple actions that can increase efficiency and thus the electricity generation.

In some of cable-driven parallel robots the end-effector position is determined by the length of cables. In fact, the length of cables is estimated by the motor''s encoder count and the end-effector position is obtained by using the direct kinematics equations. The weight and flexibility of cable lead to deflection in the cable. Therefore, the deflection of the cables leads to error in the end-effector position. Hence, the length of cables without deflection must be determined for direct kinematic equations of the robot. In this paper, first of all inverse and direct kinematics equations of Samen SpaceCam cable-driven robot are derived. Next, length of the cables without deflection is calculated for the direct kinematic of the robot. Finally, we compare the end-effector positions obtained from the actual cable length and without deflection one together.

In order to maximize system performance and achieve higher production quality, complexity of processing systems increased continually. Hence, process monitoring and fault detection become important parts of modern systems. In this paper, a fault detection system has been designed for a heading measurement unit of an Attitude and Heading Reference system (AHRS). AHRS is one of the most important parts in the preset and inertial navigation systems (INS). In this regards, at First, AHRS processing circuits of an AUV have been analyzed and simulated. Then, a fault detection scheme based on neural network has been designed. Simulation results show acceptable performance of the proposed scheme in detecting faults.

Recently, many studies have been published about the effect of piezoresistivity in silicon nanowires (SiNW). These studies indicated that piezoresistivity effect in SiNW is much higher than this value for Bulk Silicon. If these nanowires could be used in the sensing devices, the sensitivity of various types of these devices can be increased. In this paper uses COMSOL software to examine the effect of Silicon in bulk sizes (one piece with dimensions of 40mm×60mm) and SiNW. For this purpose, the P-type piezoresistivity silicon impurity concentration equal to be used.Taking a square diaphragm 1000×100μm and applying pressure to find the points on diaphragm with the greatest amount of stress, so put the piezoresistance at these points. By changing the parameters of the SiNW, length, position on the diaphragm, release hight and the number of mesh nodes, the optimal parameters for nanowires with high piezoresistivec effect is obtained. The simulation results in pressure 100kPa, obtained the DR/R equal to 0.306 for bulk silicon and R/R for SiNW with dimensions 0.25mm×0.250mm and length of 10mm is 0.5943, Show that the piezoresistive effect of the nanowires more than 19 times greater than the piezoresistive effect on bulk silicon. The use of nanowires in sensing devices including pressure sensors, accelerometers, etc. will increase their sensitivity and resolution.

Ball bearing is one of the most widely used and critical parts in machines. The failure of rolling element bearings is one of the most important causes of breakdown in rotary machines. Vibration of each machine is a good factor in realizing the condition of machines. So far, various vibration-based techniques have been developed for analyzing vibration signals. These methods are used in different domains to monitor the condition of bearings. Wireless modules can be used to solve the limits of access in machines especially in rotating machinery.In this paper, a wireless accelerometer sensor for remote condition monitoring of rolling bearings has been developed. The fabricated system works in high sample rate and has been tested on six roller bearings with different defects. This project shows that wireless sensors offer an effective method for monitoring key parts of machines continuously and remotely.