Design Of Controller For Mobile Robot Research Articles

Augmented obstacle avoidance controller design for mobile robots

Abstract For unicycle robots and an arbitrary continuous reference tracking controller, we propose a mildly invasive obstacle avoidance augmentation only activated in an eye-shaped neighborhood around an obstacle and providing avoidance guarantees. Switching between different control phases is orchestrated by a hybrid automaton with hysteresis mechanisms that prevent Zeno behavior. Since the size of the eye-shaped neighborhood and its orientation depend continuously on the orientation and velocity of the robot, the velocity control input is continuous. Numerical simulations illustrate the performance of an avoidance-augmented tracking controller.

A Novel Virtual-Structure Formation Control Design for Mobile Robots with Obstacle Avoidance

The cooperative motion of multiple mobile robots has attracted wide attention due to its advantages in military, marine and aerospace fields, and formation control has become a significant technology in the realization of these tasks. However, most of the existing formation control designs of mobile robots do not consider the practical obstacles in the environment, and the maintenance of both formation and trajectory tracking while confronting the obstacles is still a challenging issue. Therefore, in this paper, a virtual-structure-based formation control approach is designed with obstacle avoidance for a system with multiple mobile robots. The basic trajectory is generated for each robot in the group and parameterized to keep the group in formation. A trajectory generator is then established regarding the obstacles, where a potential function is designed to adjust the basic trajectory and replan the reference trajectory to achieve obstacle avoidance. Then, a novel design for the path parameter is proposed to improve the performance of the robot group when encountering obstacles. Finally, a tracking controller is designed to achieve good tracking performance for robots, and the guaranteed performance is achieved via the Lyapunov theorem. A comparative simulation with three sets is carried out, where an objective function Fobj is designed to evaluate the tracking performance in the presence of obstacles. Besides this, a real experiment is implemented to further verify the effectiveness. The simulation and experimental results verify the good formation and tracking performance of the proposed design for a system with multiple mobile robots with obstacle avoidance.

Real-Time Control of Mobile Robot Using HMM-based Speech Recognition System

Human-robot interaction (HRI) is a significant area of interest in robotics which has attracted a wide variety of studies in recent years. In order to provide natural human-robot interaction, robots will have to acquire the skills to detect and to integrate meaningfully information from multiple modalities. In this paper, a practical speech-controlled mobile robot car system is presented and discussed. In this study the developed Hidden Markov Model (HMM) with separate word recognition system and real-time control were obtained on a mobile robot. Mel-Frequency Cepstral Coefficients (MFCC) were applied as features for the control design of mobile robot. In the study, 270 speech commands (İLERİ=forward, GERİ=backward, DUR=stop, SAĞA=right, SOLA=left) which are collected from 54 different people were applied to a series of mathematical operations and 12 cepstral coefficients were derived. Therefore, a database was generated by 12 cepstral coefficients. Thus, HMM model was trained and tested according to database. Speech data were classified in two groups as 90% training data and 10% test data. The recognition success rate of test commands was measured 94%.

A Vision-Based Real-Time Mobile Robot Controller Design Based on Gaussian Function for Indoor Environment

In this study, a visual servoing go-to-goal behavior controller is designed to control a differential drive mobile robot for a static target. Inputs for the controller method are based on a weighted graph or a triangle trigonometry kinematic model. The controller is designed with general Gaussian function by adapting the differential drive mobile robot dynamics. State parameters of dynamics are obtained by processing images in real time. It is aimed to develop an efficient internal sensor-independent visual-based control method. The single-head camera takes image frames from indoor environment. A real-time tracking process tracks the robot and target in sequential frames. The distances between graph nodes or the angles between edges are assigned as main control inputs according to utilized kinematic model. The velocity of wheels is computed for both models by using the general Gaussian function. We compare our method with two classical control methods that are PID and fuzzy-PID. Control of mobile robot has been made with high accuracy by using the designed visual-based controller.

Finite time SDRE control design for mobile robots with differential wheels

The State-dependent differential Riccati equation (SDDRE) control design for mobile robots with differential wheels is introduced for the first time, considering holonomic and non-holonomic constraints. Differential constraints of wheels put the SDDRE or even conventional State-dependent Riccati equation (SDRE) controller into uncontrollability condition. Since the actuators of wheels are not directly related to coordinates of the base, a proper kinematic transformation in design provided that relation; as a result, controllability of the controller over mobile robot was obtained. Moreover, finite time structure of the SDDRE resulted in terminal time control. Simulation data confirmed the accuracy and capability of the proposed design in nonlinear optimal control domain for both regulation and trajectory tracking cases. Time analysis of the controller was presented to assess the effectiveness of the SDDRE design for the final boundary condition. The SDRE was compared with output feedback linearization control to verify the proposed structure and to show the performance of design.

Trajectory-tracking controller design with constraints in the control signals: a case study in mobile robots

SUMMARYThis paper is a continuation of a previous work of authors, Scagliaet al. [G. J. E. Scaglia, L. M. Quintero, V. Mut and F. Di Sciascio, “Numerical methods based controller design for mobile robots,”Robotica27(2), 269–279 (2009)]. A method is presented to choose the controller parameters such that, the values of the control actions do not exceed the maximum allowable and the tracking errors tend to zero. In addition, the analysis of the controller design parameters is included. The experimental results (laboratory experiments and a real world application) demonstrate the efficiency of the controller.

Adaptive controller design for mobile robots

A simple yet effective method to reduce the dimensions of the input variables and is adaptive to various users for intelligent controllers is proposed. The method has been developed specifically to address the challenge due to fuzziness in the system inputs, especially when studying the relationship of a large mapping between input variables and system response outputs. The proposed method exploits the principal components analysis to reduce the number of inputs and uses a fuzzy c-means technique to cluster them. The objective is to extract significant principal components for adaptive neural fuzzy inference systems (ANFIS) learning. The method has been applied to a robotic walker system for elderly movement assistance. Experimental results demonstrate the feasibility of the proposed method.

Trajectory Tracking Controller Design for Mobile Robots with Bounded Input

In this paper, the robust trajectory tracking problem has been addressed for nonholonomic wheeled mobile robots with dynamic uncertainties, disturbance and actuator constraints. control theory, LMI theory and principle of MPC are utilized to design robust tracking controller. Simulation is performed to highlight the effectiveness of the proposed control law.

Integrated Backstepping Mobile Robot Controller Design by Applying Sum of Squares Approach

The paper presents a sum of squares (SOS) based backstepping control design method for a three wheels omni-directional mobile robot. The characteristic of the strict-feedback system associated with...

Numerical methods based controller design for mobile robots

SUMMARYThis paper presents the design of four controllers for a mobile robot such that the system may follow a preestablished trajectory. To reach this aim, the kinematic model of a mobile robot is approximated using numerical methods. Then, from such approximation, the control actions to get a minimal tracking error are calculated. Both simulation and experimental results on a PIONEER 2DX mobile robot are presented, showing a good performance of the four proposed mobile robot controllers. Also, an application of the proposed controllers to a leader robot following problem is shown; in it, the relative position between robots is obtained through a laser.

Numerical methods based controller design for mobile robots

This paper presents the design of four controllers for a mobile robot such that the system may follow a pre-established trajectory. To reach this aim, the kinematic model of a mobile robot is approximated using numerical methods. Then, from such approximation, the control actions to get a minimal tracking error are calculated. Both simulation and experimental results on a PIONEER 2DX mobile robot are presented, showing a good performance of the four proposed mobile robot controllers.

A Straight Lines Path Following Strategy Applicated to a Tricycle Vehicle

Abstract In modern automatic control theory, the path maching problem including straight line path controller design for mobile robots has recently been subject of increasing interest. This paper deals with the application of path tracking strategy for a tricycle vehicle. A method is proposed for an exact path maching without discontinuity in robot trajectory. A praticai implementation of this strategy on an industrial tricycle gives convincing experimentation results.