Applied Science Private University

About: Applied Science Private University is a education organization based out in Amman, Jordan. It is known for research contribution in the topics: Catalysis & Population. The organization has 4124 authors who have published 5299 publications receiving 116167 citations.

Embedded System for Motion Control of an Omnidirectional Mobile Robot

Abstract: In this paper, an embedded system for motion control of omnidirectional mobile robots is presented. An omnidirectional mobile robot is a type of holonomic robots. It can move simultaneously and independently in translation and rotation. The RoboCup small-size league, a robotic soccer competition, is chosen as the research platform in this paper. The first part of this research is to design and implement an embedded system that can communicate with a remote server using a wireless link, and execute received commands. Second, a fuzzy-tuned proportional–integral (PI) path planner and a related low-level controller are proposed to attain optimal input for driving a linear discrete dynamic model of the omnidirectional mobile robot. To fit the planning requirements and avoid slippage, velocity, and acceleration filters are also employed. In particular, low-level optimal controllers, such as a linear quadratic regulator (LQR) for multiple-input-multiple-output acceleration and deceleration of velocity are investigated, where an LQR controller is running on the robot with feedback from motor encoders or sensors. Simultaneously, a fuzzy adaptive PI is used as a high-level controller for position monitoring, where an appropriate vision system is used as a source of position feedback. A key contribution presented in this research is an improvement in the combined fuzzy-PI LQR controller over a traditional PI controller. Moreover, the efficiency of the proposed approach and PI controller are also discussed. Simulation and experimental evaluations are conducted with and without external disturbance. An optimal result to decrease the variances between the target trajectory and the actual output is delivered by the onboard regulator controller in this paper. The modeling and experimental results confirm the claim that utilizing the new approach in trajectory-planning controllers results in more precise motion of four-wheeled omnidirectional mobile robots.

Experimental Study of Formation Damage Caused by Complete Water Vaporization and Salt Precipitation in Sandstone Reservoirs

Abstract: Vaporization of water during both gas reservoir development and \(\hbox {CO}_2\) geological sequestration in saline formations can cause salt precipitation with rapid loss of formation porosity and permeability. In this work, laboratory experiments were conducted to evaluate the effects of complete formation water evaporation and salt precipitation on the physical properties of sandstone samples by analyzing the decreases in both core porosity and permeability and the changes of pore distribution after salt precipitation using capillary flow porometry. Experimental results indicated that porosity can be decreased by 14.6 % and permeability can be decreased by 83.3 % due to salt precipitation under the experimental condition (100 \(^{\circ }\hbox {C}\) and 0.101 MPa). The higher the salinity and lower the initial formation permeability, the greater is the decrease in permeability. The permeability reduction can be approximated with a power-law relationship to the porosity reduction. Sodium chloride (NaCl) was the major precipitated salt crystal. The precipitated salt will cause small pores to be blocked, which leads to reduced total pore volume and total effective pore volume. The experimental results also suggested that the impact of salt precipitation on pores with smaller diameter was found to be greater than on those with larger diameter.

Performance optimization of tethered balloon technology for public safety and emergency communications

Abstract: This paper investigates the potential of a tethered balloon network architecture deployed as part of public safety networks and emergency communications. Tethered balloon technology has been evolving as a powerful and promising technology for improving public safety and for saving people’s lives. As such, it enables accomplishment of unique and specific missions for temporary events such as natural hazardous or terrorist acts. Such acts raise significantly the potential to disrupt the entire terrestrial wireless communication infrastructure. To mitigate the effects of such catastrophic events, we propose tethered balloon technology for delivering broadband services in an area over which the communication infrastructure has been entirely or partially destroyed. The results reveal a significantly high performance in providing broadband communication services with provision of Quality of Service. This suggests that the work of rescue and relief teams can be significantly enhanced.