Design and Steering Control of a Center-Articulated Mobile Robot Module

This paper discusses the design and steering control for an autonomous modular mobile robot. The module is designed with a center-articulated steering joint to minimize the number of actuators used in the chain. We propose a feedback control law which allows steering between configurations in the plane and show its application as a parking control to dock modules together. The control law is designed by Lyapunov techniques and relies on the equations of the robot in polar coordinates. A set of experiments have been carried out to show the performance of the proposed approach. The design is intended to endow individual wheeled modules with the capability to merge and make a single snake-like robot to take advantage of the benefits of modular robotics

Improving path-tracking performance of an articulated tractor-trailer system using a non-linear kinematic model

This paper presents a novel non-linear mathematical model of an articulated tractor-trailer system that can be used, in combination with receding horizon techniques, to improve the performance of path tracking tasks of articulated systems. Due to its dual steering mechanisms, this type of vehicle can be very useful in precision agriculture, particularly for seeding, spraying and harvesting in small fields. The articulated tractor-trailer system model was embedded within a non-linear model predictive controller and the trailer position was monitored. When the kinematic of the trailer was considered, the deviation of trailer's position was reduced substantially alongside not only straight paths but also in headland turns. Using the proposed mathematical model, we were able to control the trailer's position itself rather than the tractor's position. The Robot Operating System (ROS) framework and Gazebo simulator were used to perform realistic simulations examples.Fil: Murillo, Marina Hebe. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Sánchez, G.. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Deniz, Nestor Nahuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Genzelis, Lucas Manuel. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; ArgentinaFil: Giovanini, Leonardo Luis. Consejo Nacional de Investigaciones Científicas y Técnicas. Centro Científico Tecnológico Conicet - Santa Fe. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional. Universidad Nacional del Litoral. Facultad de Ingeniería y Ciencias Hídricas. Instituto de Investigación en Señales, Sistemas e Inteligencia Computacional; Argentin

A Novel Relative Navigation Control Strategy Based on Relation Space Method for Autonomous Underground Articulated Vehicles

This paper proposes a novel relative navigation control strategy based on the relation space method (RSM) for articulated underground trackless vehicles. In the RSM, a self-organizing, competitive neural network is used to identify the space around the vehicle, and the spatial geometric relationships of the identified space are used to determine the vehicle’s optimal driving direction. For driving control, the trajectories of the articulated vehicles are analyzed, and data-based steering and speed control modules are developed to reduce modeling complexity. Simulation shows that the proposed RSM can choose the correct directions for articulated vehicles in different tunnels. The effectiveness and feasibility of the resulting novel relative navigation control strategy are validated through experiments

Steering Kinematics for a Center-Articulated Mobile Robot

This paper discusses the steering kinematics for a center-articulated mobile robot. Several models have been recently proposed in the literature and we use experimental data to compare and validate these models. The vehicle heading response to steering command is shown to include a dominant zero due a nonholonomic constraint, and this is verified by experiments conducted using a 30-t mobile vehicle at our laboratory. Simulation results are then used to show the significance of this zero and its effect on closed-loop heading angle contro

Raskaiden pyörällisten mobiilirobottien mallinnus, simulointi ja radanseuranta

Autonomous vehicles have been studied at least since the 1950s. During the last decade, interest towards this field of study has grown imposingly. Path-following control is one of the main subjects among autonomous vehicles. The focus in path-following control is in controlling of the pose of the vehicle to match with the desired pose, which is provided by a specified path or trajectory. Usually the pose is represented in a two-dimensional world frame by the means of x and y coordinates and angle of heading. The methods used in this thesis are modelling and simulation (M&S). M&S of physical systems is a well-recognized field of expertise among engineering sciences. Rapid system prototyping, control designing, or studying an existing system by the means of M&S provide possibilities for observing, developing, and testing under risk-free environment. In this thesis, using the M&S methods provides possibilities for fast and economical evaluation of the designed algorithms before considering prototype testing with actual systems under real environments. Objectives of the thesis are to implement dynamic robot models of two vehicles, design high-level controller structures for their actuators, implement a path-following controller, and study the behaviour of the robots during various autonomous path-following scenarios. The vehicles to be modelled are Ponsse Caribou S10 and Haulotte 16RTJ PRO. The exact study vehicles are owned by Tampere University of Technology. Results from closed loop path-following control of the modelled robots denoted accurate path-following under well-behaved path curvatures, generally with a mean absolute lateral position error less than 0.1 m. In the best simulation results, mean position errors were under of 0.05 m. The implemented controllers proved to be effective at the whole velocity range of the forwarder Ponsse Caribou S10. The implemented high-level inverse kinematic controllers succeeded in synchronous commanding of the robots’ actuators. Due to the forming of the inverse kinematics, the path-following controller was able to output identical control signals independent of the steering structure of the vehicle, thus permitting a possibility for future development among more advanced path-following control