To Örebro University

The requirements of the working and safety norms demonstrate significant need of increased efficiency and improved working conditions in cleaning confined spaces. This paper presents an overview of the existing technologies and solutions for cleaning large confined spaces. A special attention is directed for cleaning interior surface of confined spaces used mainly for storing bulk materials or liquids, such as silos. The cleaning technologies for confined space depend on several aspects as the build-up material, the surface material, the ambient conditions. Four cleaning techniques are presented in this paper. The mechanisms and robots related to the studied problem are surveyed and evaluated from the viewpoint of their capability to clean interior surfaces. The dominating majority of the existing cleaning equipment is constructed to serve cleaning the entire volume of the respective confined space (silo), but not for cleaning the interior surface.

We present the field tests and measurements performed on a novel current collector manipulator to be mounted beneath a heavy vehicle to collect electric power from road embedded power lines. We describe the concept of the Electric Road System (ERS) test track being used and give an overview of the test vehicle for testing the current collection. The emphasis is on the field tests and measurements to evaluate both the vertical accelerations that the manipulator’s end-effector is subject to during operation and the performance of the detection and tracking of the power line.

All mechanical systems are subjected to dynamic forces when they are in functioning. Thus a dynamical analysis has to be studied to determine the system behaviour. The vibration is of interest to study, due to its destructive or constructive effect. In the present era computational techniques are quite common and are very reliable as far as the modal analysis is concerned. In this work, the robot of silo cleaning is analysed for its vibration behaviour using finite element method (FEM).The robot was modelled and meshed in ANSYS. Modal analysis was conducted to calculate few initial natural frequencies. After carrying out the modal analysis, harmonic and transient analysis were done to see the response of the robot under dynamic loading. It was observed that robot is safe in its entire range of operation.

Underwater robots are being developed for various applications ranging from inspection to maintenance and cleaning of submerged surfaces and constructions. These platforms should be able to travel on these surfaces. Furthermore, these platforms should adapt and reconfigure for underwater environment conditions and should be autonomous. Regarding the adhesion to the surface, they should produce a proper attaching force using a light-weight technics. Taking these facts into consideration, this paper presents a survey of different technologies used for underwater cleaning and the available underwater robotics solutions for the locomotion and the adhesion to surfaces.

We present the adopted motion control schemes of a novel current collector manipulator to be mounted beneath a heavy hybrid electric vehicle to collect electric power from road embedded power lines. We describe our approach of power line detection and tracking based on an array of inductive proximity sensors. The emphasis is on the adopted motion control logic for sequential and closed loop motions to detect and track the power line respectively. We implement the sliding mode control approach for the closed loop control scheme as straightforward solution given the binary nature of the inductive proximity sensors being used. The overall architecture of the entire motion control system is presented. Finally, the implementation of the entire control logic in a form of a state machine is discussed.

This paper presents the mechanical design and the control system architecture of anunderwater robot, developed for bio-fouling cleaning surfaces. The robotic system presented herehas been designed to improve the productivity, reduce the environmental impacts, and excludethe hazards for the operators. The control system has a layered structure which is distributed intotwo blocks: cleaning robot, and on-board base station connected with power and control cablesand a water hose, to facilitate different modes of operations and to increase the system reliability.A low level control has been implemented on the robotic platform. The onboard station designedto be in different layers of the control system: manual, semiautonomous and autonomous modes.A scaled prototype has been implemented and tested to prove the concept, and to make certainthat the mechanical design and the chosen control system are perfectly suited to the mainfunctions of the robotic system.

Both the principle of operation and the motion-control system of a suspended robot for surface cleaning in silos are presented in this paper. The mechanical design is a reasonable compromise between basically contradictory factors in the design: the small entrance and the large surface of the confined space, and the suspension and the stabilization of the robot. The design consists of three main parts: a support unit, the cleaning robot and a cleaning mechanism. The latter two parts enter the silo in a folded form and, thereafter, the robot’s arms are spread in order to achieve stability during the cleaning process. The vertical movement of the robot is achieved via sequential crawling motions.

The control system is divided into two separate subsystems, the robot’s control subsystem and a support-unit control subsystem, in order to facilitate different operational modes. The robot has three principle motion-control tasks: positioning the robot inside the silo, holding a vertical position during the cleaning process and a crawling movement.

A scaled prototype of the robot has been implemented and tested to prove the concept, in order to make certain that the mechanical design suits the main functions of the robotic system, to realize the robot’s design in an industrial version and to test it in a realistic environment.

This paper presents a prototype of a novel current collector manipulator that can be mounted beneath a road vehicle between the front and rear wheels to collect electric power from road embedded power lines. The ground-level power supply concept for road vehicles is described and the kinematic model of this two degree of freedom manipulator is detailed. Finally, the power line detection, based on an array of inductive sensors, is discussed.

We present a prototype of a novel current collector manipulator to be be mounted beneath a heavy vehicle to collect electric power from road-embedded power lines. We describe the concept of the ground-level power supply system for heavy vehicles and its main components. The main requirements and constraints, such as safety, robustness to harsh road and weather operational conditions, ambient environment aspects and dynamic properties, are introduced. The emphasis is on the developed kinematic model, which provides the base for further development of the control system. We propose and derive an alternative approach for representing the inverse kinematics by a two-dimensional polynomial approximation that avoids the usage of complicated non-linear equations. Its simplicity is demonstrated by a numerical example with the basic parameters of the prototype. The basic motion sequences of the current collector and the way to control them are outlined. 

This paper introduces a new concept of flexible crawling mechanism in the design ofindustrial in-water cleaning robot, which is evaluated from the viewpoint of work and operationon an underwater surface. It enables the scanning and cleaning process performed by water jets,while keeping stable robot position on the surface by its capacity to bear and compensate the jetreactions. Such robotic platform can be used for cleaning and maintenance of various underwatersurfaces, including moving ships in the open sea. The designed robot implements its motions bycontraction and expansion of legged mechanism using standard motors and suction cupstechnology. In this study we focus at the conditions for achieving enough adhesion for keepingcontinuous contact between the robot and the surface and robot stability in different situations forthe basic locomotions.