Øyvind Netland

Software Module Real-Time Target: Improving Development of Embedded Control System by Including Simulink Generated Code Into Existing Code

The method presented in this paper, Software module real-time target (SMRT), aim to make code generated by Simulink Coder easy to include into a real-time embedded code project. It is intended to give developers experienced in embedded programming better control and flexibility when using Simulink Coder, without having to understand the code generation process. A general methodology, SMRT, has been defined, and a library for using SMRT has been implemented for Xenomai Linux. The library can be modified for other operating systems. This solution has been tested on a Beagle bone development board and used in the development of a robot prototype.

Two pilot experiments on the feasibility of telerobotic inspection of offshore wind turbines

With cyber-physical systems, it is not necessary to be physically present at a location to perform work there. Inspection of offshore wind farms is a task that would be beneficial to do remotely, due to the time and high cost required for accessing the turbines for manned inspections. Such remote inspections must be equally effective at finding errors in the turbines, since errors that arent found can cause expensive failures. This paper describes a remote inspection robot prototype, and how it was used to compare participants ability to identify errors using remote and manned inspections in two experiments. The results demonstrated that errors with both known and unknown symptoms were successfully identified using remote inspections, although not as effectively as manned. This is considered promising for remote inspections, and what we have learned in these experiments is used in the planning of a larger experiment, and in the development of an improved prototype.

Prototyping and evaluation of a telerobot for remote inspection of offshore wind farms

A telerobot can be used for inspection at a location far from where its user is, i.e. remote inspection. This paper presents the design and implementation of a lab for evaluation of remote inspection, consisting of a telerobot prototype and an environment for it to operate in. Remote inspection can be used in many industries, but we argue that it is especially suitable for offshore wind turbines, since these are large, unmanned and complicated machines at difficult to reach locations. Remote inspection of offshore wind turbines has the potential to reduce the maintenance cost, increase the knowledge of the turbines condition and the predictability of maintenance. The typical user of remote inspection is expected to have expertise in maintenance, not robotics. Therefore we suggest evaluating remote inspection using usability tests, which consider how easy it is to learn, and use a system for its intended purpose.

Evaluation of undesirable deformations in complex, hollow aluminium extrusions due to roll bending

This paper presents a series of experiments where an aluminium extrusion with a complex, hollow cross-section was formed by roll bending. The extrusion is intended to be used as a rail for a mobile instrumentation platform that requires both straight and bent rail sections in different configurations. In order to develop the system to be highly accurate, precise and functional under all operating conditions, it is vital to know the ‘nominal’ local cross-sectional deformations due to the bending process, and the associated tolerances that can be achieved. The results presented herein are based on nine rail segments that underwent identical bending operations. The differences between the rails were found to be relatively small as seen from a product functionality perspective; thus, the observed deformations are considered acceptable for the application considered. These results will also serve as a reference for future experiments with other bending parameters and methods in the efforts to identify the most...

An Experiment on the Effectiveness of Remote, Robotic Inspection Compared to Manned

This paper evaluates the effectiveness of remote inspections using a robot in a laboratory experiment. The experiment differs from most human-robot interaction experiments in its direct comparison of manned and robotic operations. 21 participants each performed three manned inspections and three inspections with each of the two remote inspection methods, teleoperated and assisted. The effectiveness was measured based on the number of errors they were able to identify. Teleoperated inspections were found to be less effective than manned, although this difference was not statistical significant. Assisted inspections, implemented as an interactive simulation prototype representing a robot with higher autonomy, had similar effectiveness as manned. Because of the time and high cost required for manned inspections of offshore wind turbines, remote inspection can give a large economic benefit. However, this will only be a viable alternative if the robot system is inexpensive and remote inspections are as effective for identifying errors as manned inspections, which the experiment presented here suggests.

Adaption of MathWorks Real-Time Workshop for an Unsupported Embedded Platform

This paper describes how to configure MathWorks Real-Time Workshop to automatically build a control system application for an unsupported embedded computer platform. The application can be generated with a single command, allowing for quick iterations of testing and debugging. The I/O interface and control algorithm of the application is described in a Simulink model. In this paper an AVR32 embedded computer running AVR32-Linux was used, but it should also be relevant for adapting Real-Time Workshop for other embedded platforms.

Dependable Cyber-Physical Systems with Redundant Consumer Single-Board Linux Computers

There are a large number of small and inexpensive single-board computers with Linux operating systems available on the market today. Most of these aim for the consumer and enthusiast market, but can also be used in research and commercial applications. This paper builds on several years of experience with using such computers in student projects, as well as the development of cyber-physical and embedded control systems. A summary of the properties that are key for dependability for selected boards is given in tabulated form. These boards have interesting properties for many embedded and cyber-physical systems, e.g. high-performance, small size and low cost. The use of Linux for operating system means a development environment that is familiar to many developers, and the availability of many libraries and applications. While not suitable for applications were formally proven dependability is necessary, we argue that by actively mitigating some of the potential problems identified in this paper such computers can be used in many applications where high dependability is desirable, especially in combination with low-cost. A solution with redundant single-board computers is presented as a strategy for achieving high dependability. Due to the low cost and small size, this is feasible for applications were redundancy traditionally would be prohibitively too large or costly.

Control of Cyber-Physical Systems Using Bluetooth Low Energy and Distributed Slave Microcontrollers

In this paper, Bluetooth Low Energy is used for communication between master computers and distributed slave microcontrollers that perform low-level tasks that the master is unable or not suitable to do, e.g. hard real-time and low-level I/O. The wireless communication with the master computer allow slaves to be added, replaced or removed without the need for rewiring. Dependability can be increased as implementation of redundancy, both for masters and slaves, does not require wired connections between them. This concept has been utilized in an industrial prototype and evaluated in an experiment presented in this paper. The experiment evaluated the communication latency with Bluetooth Low Energy, compared to a wired alternative, which is important for reliable operation. The results showed a similar average latency, but the worst case was less favorable for Bluetooth Low Energy. However, since the slaves are intended to manage time critical operations locally, with the master computer in a supervisory role, these delays will be acceptable in many applications, when considering the advantages of a wireless master-slave communication.