Erik Prada

Snake Robot Movement in the Pipe Using Concertina Locomotion

Inspection tasks of pipes or channels are part of the engineering practice. In the past there were investigated conventional approaches like wheeled-based mechanisms. This paper deals with unconventional approach - snake robot moving in the pipe. In the paper locomotion pattern of concertina is introduced and subsequently kinematic model of concertina locomotion is established. Main requirements and conditions of presented locomotion pattern are stated. Using software Matlab the kinematic model is simulated according designed locomotion pattern in order to verify the kinematic model. For experimental purposes the experimental snake robot – LocoSnake is used. Simulation and experiment are compared and evaluated.

Algorithm for determining static characteristic on electromagnetic actuator for rectilinear locomotion structure of a snake-like robot

This work deals with the determination of static characteristics of electromagnetic actuator. Electromagnetic actuator is designed as drive for rectilinear locomotion structure parts of snake-like robot. Static characteristics are determined by the solving of a non-linear problem of the actuators magnetic circuit in a ferromagnetic cores particular positions and at the different fluxional rates of the coil. Static characteristics are represented by a L induction, magnetic force affecting ferromagnetic core Fm. For the calculation of the coil induction L is used the power of magnetic field. Magnetic field power is calculated by using Maxwell stress tensor and differential formula by a numeric derivation way.

Intelligent in-pipe machine adjustable to inner pipe diameter

The paper concerns to area of in-pipe locomotion. Traditional conceptions of in-pipe machines tend to wheels slipping or self-blocking. Several design stages of improved in-pipe machine are shown. Design of in-pipe machine coming from conception of computer controlled electromechanical device. Final design solution will be able to locomote inside pipe with variation of inner diameter in range from 100 to 200 mm with automatically adjustment to pipe diameter.

Simulation Analysis of Pneumatic Rubber Bellows for Segment of Hyper-Redundant Robotic Mechanism

The paper deals with a design and simulations of segment for hyper-redundant manipulator. In the paper 6-DOF manipulator segment, which consists of pneumatic and electromagnetic actuators, is designed. CAD model of the segment is introduced and basic parts are described. The basic motion is reached by pneumatic actuator which works through the rubber bellows and it utilizes their expansion properties. Main focus of the study besides segment design is analysis of rubber bellows. From this reason FEM analysis is done in software SolidWorks. In the conclusion the results are discussed.

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.

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.

Kinematic analysis of snake-like robot using obstacle aided locomotion

This paper deals with an obstacle aided locomotion of snake-like robot, which is the actual problem in the field of mechatronics. Because of many snakes using this kind of locomotion, the first step and hereby the most important is a kinematic analysis. The Denavit-Hartenberg convention was applied for this purpose. By this method the position vector components of each link according to basic coordinate system placed into any obstacle was assigned. Kinematic problem is a stepping-stone to the dynamic solution.

Friction Force Identification for Machine Locomotion

This paper describes the basic characteristic of the in-pipe micromachine. Themicromachine is based on two masses impact principle. Its diameter is 10 mm, length is 45 mm andweight is 10g. The micromachine is composed of a electromagnet, a permanent magnet, a adjustingunit, a guide rod, a damping spring and bristles. The paper represents the methods of friction forcesidentification

Simulation and Determination of the Influence of the Gait Function on the Change of the Shape of a Snake-Like Robot

This article discusses the application of the Hirose ́s function for the achievement of the serpentine locomotion of the snake-like robot. Verification of the accuracy of locomotion was performed by simulation in the MATLAB 2012a program. At the beginning of the article, the biological aspects and the principle of the snake’s locomotion are mentioned. In the following chapter, the basic Hirose ́s function, which is subsequently transformed into the discreet shape in the Cartesian coordinates, is described. Moreover, relations for the calculation of rotation angle of the individual segments, wrapping angle and other similar parameters have been obtained. At the end of the article, simulations have been performed within which the influence of changes of the individual parameters of the function on the change of the shape of the snake-like robot have been observed.

Stepper Motor Control by ATMEL AVR Microcontroller

The paper deals with stepper motor control using microcontroller ATmega8-16PU. In the paper are mentioned two ways of control, namely full-step mode and half-step mode control. At first, bipolar stepper motor is introduced. Next, there is created measuring stand consisting of bipolar stepper motor with one step angle 1.8° and encoder with 360 CPR. During the experiment were measured angular velocities by I/O measuring card MF624 cooperating with Matlab/Simulink. The results show differences between used two stepping modes of motor.