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In recent years, the automotive industry has been significantly affected by a number of challenges driven by globalisation, economic fluctuations, environmental awareness and rapid technological developments. As a consequence, product lifecycles are shortening and customer demands are becoming more diverse. To survive in such a business environment, manufacturers are striving to find a costeffective solution for fast and efficient development and reconfiguration of manufacturing systems to satisfy the needs of changing markets without losses in production. Production systems within automotive industry are vastly automated and heavily rely on PLC-based control systems. It has been established that one of the major obstacles in realising reconfigurable manufacturing systems is the fragmented engineering approach to implement control systems. Control engineering starts at a very late stage in the overall system engineering process and remains highly isolated from the mechanical design and build of the system. During this stage, control code is typically written manually in vendor-specific tools in a combination of IEC 61131-3 languages. Writing control code is a complex, time consuming and error-prone process.

Robotics has been considered as a viable automation solution for the aerospace industry to address manufacturing cost. Many of the existing robot systems augmented with guidance from a large volume metrology system have proved to meet the high dimensional accuracy requirements in aero-structure assembly. However, they have been mainly deployed as costly and dedicated systems, which might not be ideal for aerospace manufacturing having low production rate and long cycle time. The work described in this thesis is to provide technical solutions to improve the flexibility and cost-efficiency of such metrology-integrated robot systems. To address the flexibility, a software framework that supports reconfigurable system integration is developed. The framework provides a design methodology to compose distributed software components which can be integrated dynamically at runtime. This provides the potential for the automation devices (robots, metrology, actuators etc.) controlled by these software components to be assembled on demand for various assembly applications. To reduce the cost of deployment, this thesis proposes a two-stage error compensation scheme for industrial robots that requires only intermittent metrology input, thus allowing for one expensive metrology system to be used by a number of robots. Robot calibration is employed in the first stage to reduce the majority of robot inaccuracy then the metrology will correct the residual errors. In this work, a new calibration model for serial robots having a parallelogram linkage is developed that takes into account both geometric errors and joint deflections induced by link masses and weight of the end-effectors. Experiments are conducted to evaluate the two pieces of work presented above. The proposed framework is adopted to create a distributed control system that implements calibration and error compensation for a large industrial robot having a parallelogram linkage. The control system is formed by hot-plugging the control applications of the robot and metrology used together. Experimental results show that the developed error model was able to improve the 3s positional accuracy of the loaded robot from several millimetres to less than one millimetre and reduce half of the time previously required to correct the errors by using only the metrology. The experiments also demonstrate the capability of sharing one metrology system to more than one robot.

Robotics has been considered as a viable automation solution for the aerospace industry to address manufacturing cost. Many of the existing robot systems augmented with guidance from a large volume metrology system have proved to meet the high dimensional accuracy requirements in aero-structure assembly. However, they have been mainly deployed as costly and dedicated systems, which might not be ideal for aerospace manufacturing having low production rate and long cycle time. The work described in this thesis is to provide technical solutions to improve the flexibility and cost-efficiency of such metrology-integrated robot systems. To address the flexibility, a software framework that supports reconfigurable system integration is developed. The framework provides a design methodology to compose distributed software components which can be integrated dynamically at runtime. This provides the potential for the automation devices (robots, metrology, actuators etc.) controlled by these software components to be assembled on demand for various assembly applications. To reduce the cost of deployment, this thesis proposes a two-stage error compensation scheme for industrial robots that requires only intermittent metrology input, thus allowing for one expensive metrology system to be used by a number of robots. Robot calibration is employed in the first stage to reduce the majority of robot inaccuracy then the metrology will correct the residual errors. In this work, a new calibration model for serial robots having a parallelogram linkage is developed that takes into account both geometric errors and joint deflections induced by link masses and weight of the end-effectors. Experiments are conducted to evaluate the two pieces of work presented above. The proposed framework is adopted to create a distributed control system that implements calibration and error compensation for a large industrial robot having a parallelogram linkage. The control system is formed by hot-plugging the control applications of the robot and metrology used together. Experimental results show that the developed error model was able to improve the 3 positional accuracy of the loaded robot from several millimetres to less than one millimetre and reduce half of the time previously required to correct the errors by using only the metrology. The experiments also demonstrate the capability of sharing one metrology system to more than one robot.

The aim of this research is to bridge the gap between CAD modeling and kinematic analysis packages by extracting kinematic information directly from part genometries. It will relieve the designers from the tedious task of specifying assembly constraints and specifying redundant information for creating kinematic models. Automatic generation of kinematic assembly models is achieved by characterizing the lower kinematic pairs: cylindrical, spherical, prismatic, planar and revolute; from the geometries point of view. Based on characterization, the algorithms are developed to recognize these kinematic pairs from a pair of part genometries. The combinations of primitive genometric entities: vertices, edges and faces; forming point, line, arc and surface contacts are studied. The signature geometry is found to be associated with each type of joint. The contacts are analysed for restraining the relative motion between a pair of parts. Based on this, the form closure conditions are derived for surface, line, arc and point contacts for each type of joint. The algorithms are developed to automatically recognize these joints and to assemble them into a kinematic assembly model represented as a graph. The strength and novelty of the present procedure is that kinematic pairs can be recognized for conforming as well as non conforming genometries. A Visual Basic for Application (VBA) for Solid Works has been developed using Application Programming Interface (API) for user interaction. The part genometries can be in any 3D solid modeling neutral file format (.sat, .igs, etc) or some of the native formats of CAD softwares supported by Solid Works. The regions of interest can be directly identified through mouse pick on parts using Solid Works Graphical User Interface (GUI). The transformation matrices are derived automatically to position the parts relative to each other. The local interference between part geometries is also considered for checking the validity of the kinematic pair in the assembly. Assembly model is created and represented as a directed graph. The present implementation, built on the ACIS geometry kernel, imports the parts into SolidWorks, specifies the mating regions using a visual Basic interfaces and finally generates the kinematic assembly model as an ADAMS input file complete with part genometries, their mass properties, kinematic joints and their locations.

The diploma thesis deals with an orientation mechanism of industrial robots for mounting of pivots and screws into the mounting holes. In the first phase there is a research of inventions mainly realized in the United States Patent and Trademark Office database. Subsequently the conditions of the assembly are solved. On the base of the conditions the functional requirements are described. The diploma thesis includes seven conceptual variants, which are proposed as a 3D design. Using the basical multi-criteria method the best conceptual variant is specified. That is specified due to the accepted criterias. In the next part of the diploma thesis there is a calculation, that comprises this technically and economically most promising conceptual variant. The calculation consists of a statics, a kinematics and a dynamics of the propel, a stenght control of the mechanism and kinematics analysis of the whole mechanism. Results of the calculation are used by the detailed design of orientation mechanism, that also comprises technological production theory and a correct assembly. Economical analysis, which comprises cost of produce of this newly developed automation equipment, is worked up in the conclusion of the diploma thesis. The diploma thesis also comprises drawings. The variant solves a new conception, which can be patented as an utility model.