Integral Backstepping Control for Stabilizing an Underactuated X4-AUV

Autonomous Underwater vehicles (AUV) is one of an unmanned underwater vehicle (UUV) that work independently and can be control automatically on board without requiring a cable. The autonomous capability has great important tasks due to navigate in abyss zones and dangerous underwater mission. However, in order to stabilize the system consists of four control inputs and six degree of freedoms (DOFs) is difficult tasks because of the nonlinear dynamic and model uncertainties. This paper presents the stabilization of underactuated X4-AUV using nonlinear control techniques, integral backstepping. The key idea of integral backstepping is to design a virtual controller for each subsystem by associate with integral of tracking error. The effectiveness of the proposed control technique demonstrates by simulation

Design And Development Of An RS232-Based ROV Controller System.

The overall design of an underwater robot which includes the design of electro-mechanical components and the control circuit diagrams are introduced

IOT Based unmanned surface vehicle for water sampling and water quality application

Water bodies around the world are mostly left unmonitored. Moreover, there are lot of risk and cost involved to monitor the water quality manually. With using a set of sensors on a remotely control water vehicle the risk and cost can be reduced

Backstepping and Sliding-Mode Methods for Stabilizing an Underactuated X4-AUV

In this paper, we are interested principally in dynamic modelling of an autonomous underwater vehicle (X4-AUV) while taking into account the high order nonholonomic constraints in order to develop a new control scheme as well as the various physical phenomena, which can influence the dynamic of a swimming structure. We deal with the design of two controllers, based on backstepping and sliding-mode control techniques to stabilize altitude and attitude of an underactuated X4-AUV. The designed controllers are: full backstepping control for attitude and altitude control, and partially slidingmode control for attitude combine with altitude backstepping control. Some numerical simulations are conducted to demonstrate the effectiveness of the proposed controllers

Hull Design for ROV with Four Thrusters (X4-ROV)

In this research, an X4-ROV consisting of four thrusters is design to develop a small ROV which does not have any rudders for an observation class unmanned underwater vehicle system. Each thruster is arranged at equal intervals to the same plane, and the attitude motions of a roll, a pitch and a yaw, and the translational motion forward are realizable by changing the rotational speeds of four thrusters. In this paper, the construction of an X4-ROV system and the motion method are described, together with the added mass. A torpedo hull shape with four thrusters is draft using solidworks for fabrication of hull (body) shape using a 3d printer. The operator will communicate with ROV via open source platfor

Review of sliding mode control application in autonomous underwater vehicles

973-984This paper presents a review of sliding mode control for autonomous underwater vehicles (AUVs). The AUVs are used under water operating in the presence of uncertainties (due to hydrodynamics coefficients) and external disturbances (due to water currents, waves, etc.). Sliding mode controller is one of the nonlinear robust controllers which is robust towards uncertainties, parameter variations and external disturbances. The evolution of sliding mode control in motion control studies of autonomous underwater vehicles is summarized throughout for the last three decades. The performance of the controller is examined based on the chattering reduction, accuracy (steady state error reduction), and robustness against perturbation. The review on sliding mode control for AUVs provides insights for readers to design new techniques and algorithms, to enhance the existing family of sliding mode control strategies into a new one or to merge and re-supervise the control techniques with other control strategies, in which, the aim is to obtain good controller design for AUVs in terms of great performance, stability and robustness

Design and implementation of advanced encryption standard using verilog HDL

Encryption plays an important role in data security against third-party attacks and it is significant to safeguard sensitive data and personal information for the community. Within this era of technology, privacy and confidentiality are the essential considerations to be addressed as a result of the exponential development of the Internet. One of the main concerns involving software implementation of encryption algorithm is the possibility of slower processing when transmitting and receiving data which consequently will encounter low security level during process of encryption for real-time application. The focus of this paper is to match with the existing cryptography algorithm, 128-bit Advanced Encryption Algorithm and improving the processing speed for the design with hardware implementation. Real-time application is essential for today’s modern world and Field Programmable Gate Array approach is applied for this purpose. The optimization approaches include loop release, pipeline architecture and Look-Up-Table (LUT) which allow for exact synchronization in order to meet applications’ requirements in real time. The design is coded using the Verilog HDL and the hardware design is analyzed and tested with Altera Cyclone II-V in Quartus II and ModelSim. Through comparative analysis with previous implementation, the maximum throughput for this design is 31.37 Gbit/s for the encryption process can operate at 244.89 MHz. The complete 128-bit AES encryption cycle requires only 41 clock cycles to get the encrypted data

Design and Implementation of Advanced Encryption Standard Using Verilog HDL

Encryption plays an important role in data security against third-party attacks and it is significant to safeguard sensitive data and personal information for the community. Within this era of technology, privacy and confidentiality are the essential considerations to be addressed as a result of the exponential development of the Internet. One of the main concerns involving software implementation of encryption algorithm is the possibility of slower processing when transmitting and receiving data which consequently will encounter low security level during process of encryption for real-time application. The focus of this paper is to match with the existing cryptography algorithm, 128-bit Advanced Encryption Algorithm and improving the processing speed for the design with hardware implementation. Real­time application is essential for today's modem world and Field Programmable Gate Array approach is applied for this purpose. The optimization approaches include loop release, pipeline architecture and Look-Up-Table (LUT) which allow for exact synchronization in order to meet applications' requirements in real time. The design is coded using the Verilog HDL and the hardware design is analyzed and tested with Altera Cyclone 11-V in Quartus II and ModelSim. Through comparative analysis with previous implementation, the maximum throughput for this design is 31.37 Gbit/s for the encryption process can operate at 244.89 MHz. The complete 128-bit AES encryption cycle requires only 41 clock cycles to get the encrypted data

Backstepping control of nonholonomic car-like mobile robot in chained form

This project is attempts to stabilize an underactuated system based on the backstepping approach. The discontinuous time-invariant state feedback controller is designed for exponential stabilization of underactuated nonho-lonomic systems in chained form. System dynamic of the car-like robot with nonholonomic constraints were employed. The validity of the proposed ap-proaches is tested through simulation on a car-like vehicle using Matlab soft-ware