Tomáš Lipták

An inspection of pipe by snake robot

The article deals with development and application of snake robot for inspection pipes. The first step involves the introduction of a design of mechanical and electrical parts of the snake robot. Next, the analysis of the robot locomotion is introduced. For the curved pipe, potential field method is used. By this method, the system is able to generate path for the head and rear robot, linking the environment with obstacles, which are represented by the walls of the pipe. Subsequently, the solution of potential field method is used in inverse kinematic model, which respects tasks as obstacle avoidance, joint limit avoidance, and singularity avoidance. Mentioned approach is then tested on snake robot in provisional pipe with rectangular cross section. For this research, software Matlab (2013b) is used as the control system in cooperation with the control system of robot, which is based on microcontrollers. By experiments, it is shown that designed robot is able to pass through straight and also curved pipe.

New approach of fixation possibilities investigation for snake robot in the pipe

The research field of the snake robots provides a large scale of new information. The snake robots locomotion in pipes represents one of many complicated problems attracting the attention only in recent time period. During this study an experimental environment was designed corresponding to the pipe of U shaped cross section. This article describes a new innovative kinematic structure enabling both rotary and translational movements of links of a snake robot. Combination of these two robot constrains in constructions provides new possibilities of locomotion in a confined space. The main work contribution consists in the analysis of geometric configuration of links in static fixation according to their displacements and required actuators electric power. In the experiment with physical model the method of digital image correlation was used because of the possibilities to take the movement of high dynamic range. Contribution of this experiment furnishes new information and new approach in solving the existing problem.

The Process of Gait Generation for Snake-Like Robot with Nonholonomic Constraints

The article deals with the issue of the use of geometric mechanics in mobile robotics. In the introductory part of article, basic notions are explained that frequently occurring in the concept of geometric mechanics including definition of the undulatory locomotion. It contains the determination of mathematical model for the kinematic snake-like robot that is expressed in the form of Jacobian. Further was described the relation between the body velocity and the shape variable by the reconstruction equation and from this equation was expressed the local connection. This local connection shown using the vector fields together with the gait were used to analyze movement of the kinematic snake. The last part deals with the height functions that determine the exact value of displacement or rotation in fiber directions.

Analysis of Uncertainty of Tilt Measurement with Accelerometer

The paper deals with the analysis of uncertainty of tilt measurement using accelerometer. Low cost accelerometer based on the principle of heat array is used for tilt measurement. One chip microcontroller is used for data processing from accelerometer. The knowledge of uncertainty of measurement for this measuring chain is necessary for our application.

Snake Robot Locomotion Patterns for Straight and Curved Pipe

Abstract In the paper the locomotion of snake robot is introduced considering locomotion in straight and curved pipe. For the straight pipe locomotion was designed traveling wave locomotion pattern with sine-like wave which expands from rear of the robot to its front. For the locomotion in curved pipe was designed approach which is based on inverse kinematic model including besides primary task also secondary tasks, namely kinematic singularities avoidance task, obstacle avoidance task and joint limit avoidance task. For final inverse kinematic model was used approach of weight matrices by which can be stated the priorities of particular tasks. Both case studies were tested by experimental snake robot in order to verify introduced methodology for locomotion in the straight and curved pipe.

Modeling and control of two-link snake:

This article deals with using of geometric mechanics at modeling mixed mechanical locomotion systems. In introductory part, the division of locomotion systems and reduced motion equation, which create the mathematical model of the system, is analyzed. Further we devoted to example of mixed locomotion system—two-link snake. We created the mathematical model of this example, simulated this system, and represented other tools of geometric mechanics.

Influence of pipe geometric deviation on bristled in-pipe mobile robot locomotion

This article deals with the analysis of geometric deviations influence on in-pipe robot locomotion, which uses the principle of friction difference principle. Bristles are as carrying elements. They are mounted as cantilever beams at angle to robot body. The robot should locomote inside industrial pipelines. All pipes have geometric deviations, which come from production process otherwise from operation process. It is necessary to know about the influence of these geometric deviations on the robot locomotion.

Motion Planning of Mobile Robot

The article deals with the issue of mathematical modelling of wheeled mobile robot. The introductory part of article contains theory regarding different approaches of mathematical modelling that we used. Further we applied these methods of mathematical modelling to wheeled mobile robot and we determined the mathematical model. The last part contains the motion planning in the base space and motion planning in the fiber space. These simulations of movement were realized in MATLAB.

Friction Difference as Principle of Robot Locomotion

Paper deals with friction difference principle, which is used as basic principle of robot locomotion. Piezoactuator is used as driving unit for locomotion. Structure of robot is described and also steady state velocity is derived.

Input-state Linearization of Mechanical System

The article deals with the issue of input-state linearization of the mechanical systems. The introductory part of article contains theory about exact linearization that we used. Further we explained the basic principle and procedure of input-state linearization. Then it contains the determination of state space for mechanical systems, the computing of vector fields, the investigation of controllability and involutivity of the systems and the calculation of input and state transformation.