Mobile Robots for Offshore Inspection and Manipulation
Authors: Graf Birgit , Pfeiffer Kai 
Published: February 2016

This paper analyzes the potential to apply mobile service robots in offshore oil and gas producing environments. The required hardware and software components and abilities of such a mobile offshore inspection and manipulation robot are presented in this paper.

Possible applications of mobile service robots in an offshore environment range from simple visual inspection tasks to physical intervention with the process equipment, e.g.

for sample taking, valve turning, cleaning up minor obstructions, and operating control panels.

The first prototype of a mobile offshore inspection robot is equipped with a robotic arm which carries a camera for visual inspection as well as various application sensors such as a microphone, gas and fire sensors. It is able of both, remote and autonomous inspection of industrial process equipment. In automatic mode the robot autonomously executes preprogrammed inspection tasks. The results of all inspection tasks are saved to a database and can be reviewed by the responsible operator in the central control room at any time.

The evaluation of the first autonomous mobile robot that has ever been operated in offshore environments has proven the applicability of mobile robotics to offshore environments. Different types of inspection tasks (visual and acoustic inspection, gas measuring) have been programmed to and executed by the robot successfully without ever jeopardizing the safety of the platform or the platform personnel. The application of mobile robotics in offshore environments can reduce the level of manual human intervention required to operate a production facility thereby increasing the efficiency of the workforce, improving safety and working conditions, and improving the production economics. The successful evaluation of the first realization of a mobile inspection and manipulation robot has thus levelled the ground for future mobile robot installations in offshore environments.

Introduction

Commercial mobile robots are already applied successfully in different operation areas such as underwater inspection, cleaning, defence, rescue, and security. According to the "World Robotics Study" conducted yearly by the International Federation of Robotics (IFR), a significant increase in advanced field and mobile service robot installations is predicted for the next years (Fig. 1).

Fig. 1: Current and projected installations of service robots for professional use [1].

In the oil and gas industry, a small number of robotic devices is used in exploration and production, for example for pipe and underwater inspection and repair [2]. These devices, however, are purely remote controlled vehicles and thus require the constant control by a user during operation. The operation of semi-autonomous or fully autonomous mobile robots on an offshore oil and gas platform can reduce the level of manual human intervention required to operate the production facility, thereby increasing the efficiency of the workforce and improving safety, working conditions, and production economics. Even though the idea of applying mobile robots for assistive tasks in offshore environments and process plants is not new [3,4], no implementations of mobile robots in real offshore environments could be observed so far.

Offshore Application of Mobile Robots

Offshore platform operators spend a large amount of time with walking, transporting things, and doing regular inspection and maintenance tasks. A mobile robot for offshore inspection and manipulation can be applied to automate such frequent but simple tasks, specificallyregular supervision and maintenance tasks as well as occasional tasks evolving from operation requirements,activities with or without mechanical contact to the environment.

To execute the given tasks, the robot may operate autonomously or may be tele-operated by a remote user.