Papers by Keyword: Autonomous Navigation

Abstract: This paper introduces an automatic feeding ship that applied in breeding crabs. For realizing autonomous navigation and making feed uniform on the surface of the aquaculture ponds, the GPS and automatic feeding machine are used on the ship. Bait scatters movement was analyzed by the method of physics and geometry which based on the structure and parameters of automatic feeding machine. For getting the mathematical model of bait distribution, the least square method is adopted to fit the experimental data. On this basis, the minimum variance of the bait thickness was selected as the objective function. An optimal trajectory was generated by using golden section method.

Abstract: The solar direction is an important clue for satellite autonomous navigation. A new method for obtaining the solar direction from skylight polarization for satellite navigation is discussed. The new method is using two E-vector polarization sensors to get solar direction, and the view field of the polarization sensor is discussed.

Abstract: The development of a fuzzy navigation controller for wheeltype agricultural vehicles with mechanism steering system was presented. The fuzzy controller was designed based on heading angle error and cross track error. The incremental PID control method was used for front wheels turning control. Simulation was done based on two wheels vehicle model. Automatic navigation control system was also developed,which was made up of the upper computer and the lower controller part. The upper computer was a flat industrial computer, and the lower controller was developed by ARM7. The experiments were done in the Xiaotangshan National Demonstration Base for Precision Agriculture. The cross track error of line track using this system was less than 0.12m, and the average cross track error was 0.04m.

Abstract: This paper analyzes the defects of satellite navigation systems that exist in positioning and precision-guided weapons and pointes out the advantages and military needs of pseudolite. The autonomous navigation nonlinear mathematical model of Near Space Pseudolite SINS/CNS/SAR autonomous navigation system is established. Based on the merits of fading filter, robust adaptive filtering and particle filter, we propose a fading adaptive Unscented Particle Filtering algorithm. The proposed filtering algorithm is applied to SINS/CNS/SAR autonomous navigation system and conducted simulation calculation with the Unscented Kalman filter and particle filter comparison. The results show that the new algorithm that is proposed meets the needs of pseudolite autonomous navigation, and the navigation accuracy is significantly higher than the Unscented Kalman filter and particle filter algorithm.

Abstract: Aiming at the limitations of the orbital dynamic equations based star sensor navigation method, a star sensor /geomagnetic information utilized aircraft autonomous navigation method is proposed. Dynamic equations applicable to general aircrafts are established. System observation equations are deduced. The angle between geomagnetic and starlight vector is used as observation in the algorithm. Extended Kalman filter is used to estimate position and velocity of aircraft in the algorithm. Singular value decomposition method is used to analyze observability of the system. Simulation results show that the algorithm has many advantages including high precision, good filtering convergence and stability, and non-accumulated error. The algorithm can be used as aided navigation of inertial navigation or in occasions, which only require a general navigation precision.

Abstract: A novel new algorithm of path planning is proposed for the robot path planning based on the local data map in the robot autonomous navigation. The algorithm is used to search for the local optimal path from the current position of the robot to the target according to the known sensor data. If the robot cannot reach the target directly, the temporary target point which the robot can reach will be set up according to the optimal path. The algorithm is effective under the complicated unknown environment and moving obstacle situation which fast searching speed, it can be adapted into the practical applications and the multi-robot harmony easily. The simulation result shows that this method can provide a better planning path by comparing with the traditional planning algorithms such as artificial potential field and wall-following

Abstract: Precise navigation and localization of the autonomous rover in unknown environment is important both for its own safety as well as for its ability to accomplish engineering and scientific objectives. In order to navigation autonomously the rover should have the ability of apperceiving the environment and avoiding the obstacles. Laser range finder is used to rebuild the environment and fuzzy reasoning method is used to avoid obstacles. Most importantly the rover process the sensor data to produce an estimate of its position while concurrently building a map of the environment. The improved filter algorithm is proposed to make the method feasible.

Abstract: This paper presents the development of a small experimental rocket for the National Launching Campaign held by the DGAEM in France since 2009. The campaign organized by CNES was conducted by the French Association of Planete Sciences. The rocket design was developed by Space Club Gifu and Sasaki Lab at Gifu University. The main mission is the autonomous navigation of a quasi-satellite maneuvering with a parachute and two propellers to a target point using GPS data. The rocket is 2m long, 150mm in diameter, weight 11.4kg and made entirely of CFRP. With a solid rocket motor provided by CNES, the rocket can reach an altitude of 840m. Onboard are a pressure sensor, accelerometer, GPS and two video cameras. The video cameras begin monitoring at launch. The acceleration, velocity and position were recorded for later comparison to simulation data. While the rocket launch and quasi-satellite deployment were successful, strong winds prevented the latter from maneuvering to the target point. All components were recovered intact and all recorded data were available for analysis.

Abstract: This paper presents a hybrid obstacle avoidance methodology for autonomous navigation of a mobile robot in an unstructured environment. Decision is taken based on the classical method depending on the environmental scenario where the space between multiple obstacles is measured and the feasibility of passing the robot through any immediate pair of obstacles examined. In other cases, the decision is taken by the Fuzzy Logic controller. The developed algorithm is simulated and experimentally validated with a mobile robot platform equipped with forward-looking sonar for obstacle detection. Odometry sensors assist in localization of the mobile robot. The developed algorithm is found adequately intelligent to navigate the robot from any start position through to the desired goal position avoiding obstacles, and without taking recourse to any pre-built map. The simulated results exhibit fair agreement with the experimental results.

Abstract: A lot of studies have been conducted and published on how to control the wheeled mobile robot to reach the desired target smoothly and many simulation results have been presented. However, very few of the control theorems have been applied on a real mobile robot platform to test the feasibility. This paper focuses on the experimental validation by applying the kinematic model and the control law suggested by Siegwart et al [6] on a nonholonomic wheeled mobile robot. The omni-directional camera mounted on ceiling is used to capture the initial position of robot and monitor the trajectory. Our experiment results proved with the proposed control law, the mobile robot can reach the final goal and stop.