This paper is devoted to the exploration of three-dimensional (3-D) maneuvers using a free-swimming fishlike robot. For the sake of a better maneuverability, an Esox lucius robotic fish consisting of a yawing head, two degrees of freedom pectoral mechanism and multilink body joints together with a caudal fin is developed. With full consideration of both mechanical configuration and propulsive p...

In recent years, there is a rising interest on studying biomimetic fish-like underwater robots because of advantages from mimicking real fish's great maneuverability and high energy efficiency. However, researches about these kinds of underwater robots have not been investigated so much and there are still diverse problems in respect of using of the robotic fish in the real environment such as ...

Tracking control of the direct-drive robot manipulators in high-speed is a challenging problem. The Coriolis and centrifugal torques become dominant in the high-speed motion control. The dynamical model of the robotic system including the robot manipulator and actuators is highly nonlinear, heavily coupled, uncertain and computationally extensive in non-companion form. In order to overcome thes...

A simple easy to implement algorithm is proposed to address wall tracking task of an autonomous robot. The robot should navigate in unknown environments, find the nearest wall, and track it solely based on locally sensed data. The proposed method benefits from coupling fuzzy logic and Q-learning to meet requirements of autonomous navigations. Fuzzy if-then rules provide a reliable decision maki...

This paper presents simulation and experimental results of position-based visual servoing control process of a 6R robot using 2 fixed cameras. This method has the ability to deal with real time changes in the relative position of the target-object with respect to robot. Also, greater accuracy and independency of servo control structure from the target pose coordinates are the additional advanta...

a general robotic mechanism was presented for in-pipe inspection oflevel pipes with varied diameter or curved pipelines. the robot employed three legs comprised of parallelogram linkages mechanism which enables adapting to various elbow joints in the piping systems. the curvatures in pipeline are the most important constraints in front of the robot through navigation process. to study the adapt...

this paper presents a delay compensator fuzzy control for trajectory tracking of omni-directional mobile robots. fuzzy logic control (flc) of the robots is a suitable strategy for dealing with model uncertainties, nonlinearities and disturbances.  on the other hand, in many robotic applications such as mobile robots, delay phenomenon is able to substantially deteriorate the behavior of system's...

Quadruped robots have unique capabilities for motion over uneven natural environments. This article presents a stable gait for a quadruped robot in such motions and discusses the inverse-dynamics control scheme to follow the planned gait. First, an explicit dynamics model will be developed using a novel constraint elimination method for an 18-DOF quadruped robot. Thereafter, an inverse-dynamics...

in this paper, a new method was proposed for the navigation of a mobile robot in an unknown dynamic environment. the robot could detect only a limited radius of its surrounding with its sensors and it went on the shortest null space (sns) toward the goal. in the case of no obstacle, sns was a direct path from the robot to goal; however, in the presence of obstacles, sns was a space around the r...