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Pipeline robots, borehole robots or exploring robots that work in underground environments can be classified as underground robots. When an underground robot takes a task, tracing and mapping the track of the robot is very important. This project addresses the development of a positioning technique for stepwise underground robots, which have been developed in Durham University. This research is expected to provide a general benefit to stepwise robotic positioning systems rather than a particular robotic or other situation. The initial period of this project was the most difficult. After a few months of literature searching, no suitable positioning technique had been found. Existing techniques are suitable for surface robots, undersea robots or airborne robots but are far away from the application requirements for underground robots. Positioning technology depends on sensor techniques and measurement technologies. The underground environment restricts the use of absolute measurement technologies. Consequently, underground robotic positioning systems heavily rely on relative measurements, which can cause unbounded accumulation of the positioning errors. Moreover, underground environments restrict the use of many high precision sensors because of restricted space and other factors. Hence, the feasibility of developing high, long-term, accuracy underground robotic positioning systems was problematic. Since it was found that there was a lack of research on underground robotic positioning, fundamental investigation became necessary. The fundamentals include the dominant error and the characters of the accumulation of positioning errors. After the investigation of the fundamentals the difficulty and feasibility of developing a high long-term accuracy positioning system was understood more clearly and the key factors to improve the accuracy of a positioning system were known. Based on these, a novel parallel linkage mechanism based approach was proposed. This approach has flexibility in terms of geometrical structure and provides the possibility to improve long-term accuracy of a positioning system. Although parallel linkage mechanisms have drawn a great deal of attention from researchers in passed years, this is the first time a parallel linkage mechanism has been applied to a robotic positioning system. Consequently, new problems were generated by this application of parallel linkage mechanisms. In this project, a Principal Component Analysis (PCA) method is applied to solve the positioning problems and a particular case has been used to show how to solve these problems. Through this case, the advantages of this approach and the feasibility to improve the positioning accuracy is presented. The methodology that can be used to solve the problems for different particular cases can also be used to carry out study for general situations, which have also been illustrated. Many problems still need to be solved. At the end of this thesis, some further problems are discussed. The author of this thesis believes that the proposed approach can be applied to industrial projects in the near future.

This thesis addresses the problem of setting the balance between exploration and exploitation in teams of learning robots who exchange information. Specifically it looks at groups of robots whose tasks include moving between salient points in the environment. To deal with unknown and dynamic environments,such robots need to be able to discover and learn the routes between these points themselves. A natural extension of this scenario is to allow the robots to exchange learned routes so that only one robot needs to learn a route for the whole team to use that route. One contribution of this thesis is to identify a dilemma created by this extension: that once one robot has learned a route between two points, all other robots will follow that route without looking for shorter versions. This trade-off will be labeled the Distributed Exploration vs. Exploitation Dilemma, since increasing distributed exploitation (allowing robots to exchange more routes) means decreasing distributed exploration (reducing robots ability to learn new versions of routes), and vice-versa. At different times, teams may be required with different balances of exploitation and exploration. The main contribution of this thesis is to present a system for setting the balance between exploration and exploitation in a group of robots. This system is demonstrated through experiments involving simulated robot teams. The experiments show that increasing and decreasing the value of a parameter of the novel system will lead to a significant increase and decrease respectively in average exploitation (and an equivalent decrease and increase in average exploration) over a series of team missions. A further set of experiments show that this holds true for a range of team sizes and numbers of goals.

Through limb structure and neuromuscular control, animals have demonstrated the ability to navigate obstacles and uneven terrain using a variety of different mechanisms and behaviors. Learning from the capabilities of animals, it is possible to develop robotic platforms that can aid in the study of these motions towards the production of new technologies for military, search and rescue, and medical applications. To produce these systems, it is important to first understand the underlying dynamics and design principles existent in nature that afford creatures such dexterous and agile movements. The creation of robots with legs provide a means for studying different aspects of the dynamics of legged locomotion. This includes investigations of limb coordination for gait controller design, the role of passive compliance in dynamic running, mechanical leg design and configuration for optimal energetic output, and scalability of legged systems in both simulation and through experimentation. This thesis aims to provide insight into the design and implementation of terrestrial robotic platforms with legs. / A Thesis submitted to the Department of Mechanical Engineering in partial fulfillment of the requirements for the degree of Master of Science. / Summer Semester 2018. / July 13, 2018. / dynamic simulation, gait design, kinematics, legged robots / Includes bibliographical references. / Jonathan Clark, Professor Directing Thesis; William Oates, Committee Member; Carl A. Moore, Committee Member.

The development of manufacturing control systems is a complex and expensive task for which sophisticated development tools and techniques are needed. Although there has been some progress in the development of structured methods to aid system specification and design, there has been less headway in the development of Computer Aided Software Engineering (CASE) tools. The problem addressed is the definition of a specification and analysis formalism for manufacturing control systems, which could form the basis of such a tool. Consideration of the requirements for modelling manufacturing control systems, leads to an examination of the utility of petri net models in manufacturing. A formal petri net based model (CIMNET) is subsequently developed based on extending Coloured Petri Nets (CPN) to produce ECPN (Extended Coloured Petri Nets). The ECPN model enhances the basic CPN by the inclusion of datatypes, guarded transitions and message passing. ECPNs may then be transformed into SECPN (State Enumerated Coloured Petri Nets) which can be analysed by a form of linear time temporal logic, allowing for the formal analysis of the behaviour of control systems. The inclusion of the CIMNET formalism in a wider modelling environment is then considered. This results in a high level specification of a manufacturing control system CASE tool, embedding CIMNETS in an object oriented paradigm that allows the inclusion of rule based systems. As a corollary to the specification of the CASE tool, the relationship of the IDEF structured methodology to CIMNETs is examined and the translation of IDEF2 concepts into CIMNETs presented. A number of possible extensions to this work are considered.

An alternative between product dedicated automation and general purpose robots is presented. with the new approach a given robot is customised to fulfil the requirements of the manufacturing tasks to be automated, is programmed in terms of production tasks or can be truly automated. This allows exploitation of the natural relationship between production tasks and robot systems. Current construction of industrial robots relies on a one-to-one relationship between robot and controller. The perceived way forward with this constraint has been the functionally related general purpose Industrial Robot. paradoxically, industrial robots are 'bolted' to task specific environments which have fixed repertoires of materials and tools to act upon. Computer integration of these functional machines involves human interaction to constrain the general purpose robots to relatively simple production tasks. This increases the overall cost, levels of expertise required to program the robots and lead-times in reprogramming. Unquestionably these factors have led to a reluctance towards exploitation of industrial robots. The research undertaken endeavoured to provide an alternative to this method of automation. The research completed allows robots to be programmed in terms of production tasks and dissolves the necessity to specifically design a robot controller for a given robot configuration. A modular robotic framework which consists of a number of generic modules has been employed. A loosely coupled transputer computer network has been implemented to encompass task, robot coordination and robot axis levels. At task level a 'production orientated programming environment' reflects the corresponding manual production activities. Information is gathered from this environment to allow 'task related rules' to be formulated. These 'task rules' have been utilised to fully automate, allowing product specifications to be translated to machine actions. The robot coordination level translates global coordinates to joint actions. A set of closed loop inverse kinematic equations have been generalised to ensure that the robot controller is not dependent upon a given robotic structure. These generic equations are customised to the localised constraints of each modular robotic element of the robot structure. Robust axis control is utilised to decouple robot control at joint level. 'Mix-and match' hardware and software techniques have been created which facilitate customisation of a given robot axis, and in turn, the ascending levels of the system. Hardware design capitalised on new advances in compact components which allowed self contained modular robotics elements to be formed.

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Thesis (Ph.D.)--Lehigh University, 2009. / Adviser: John R. Spletzer.