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To meet demands of the market and customers, a novel reconfigurable robot model is developed, and the Jacobian matrix is computed for singularity analysis. It is important to select the most appropriate method with the minimum complexity for this calculation. Six different algorithms for Jacobian matrix calculations are verified and compared. The procedure of using each method is analyzed, and the most suitable one for our reconfigurable robot model is selected.

A 3-DOF reconfigurable robot model is presented with the reconfigurable parameters related to the joint types and the selection of joint positive directions. The Jacobian matrix is developed using the Vukobratovie-Potkonjak’s method, and the singularity regions are derived through the determinant of the related $3\times 3$ Jacobian matrix. Eight groups of the 3-DOF kinematic structure (TTT, TTR, TRT, RTT, TRR, RTR, RRT, and RRR) are analyzed separately, and the singular configurations of each group are given in detail.

In this paper, geometry of artificial muscle which moves forearm of robotic arm is described. We have chosen configuration which is driven with one actuator (motor, gear and winch), to check the possibility of the implementation of the desired motion. The analysis of the geometry of the selected mechanism is the first step and very important step to establish the structural stability of the artificial muscle system, which implies the possibility of the implementation of the desired motion.

This paper explores the work envelope and the work window for two 6 serial axis robot families using a unified robot model. The work envelope, or workspace, represents all possible positions which may be occupied by a mechanism during its normal range of motion (for all positions). The work window is the reachable region for any given end effector orientation and is a subset of the work envelope. It is not intuitive to define, and when assessing feasibility strategies for process planning scenarios, needs to be readily determined for various kinematic configurations. A methodology to determine the reach feasibility of a desired configuration set is presented in this research. The unified model developed using Maple and Matlab is presented. Several examples are shown to demonstrate the affect of twist angles on to the shape of a robot work window. This important kinematic property needs to be used in cases of robot selection and as a tool design feature.

Dynamic modeling of robotic systems is always a challenge, not only because of the calculation complexity, but also because of the difficulties in separating basic elements of the system mass matrix, matrix of Coriolis torques, matrix of centrifugal torques, and the matrix of gravity torques. Automatic Separation Method (ASM) is applied and compared with the traditional Newton-Euler (N-E) recursive procedure using the SCARA robotic system with three Degrees of Freedom (3 DOF). In the comparison of the two methods, it is significant that using the N-E method will require additional computing time and effort to manually separate metrics elements, while the ASM takes no time to achieve the same result. The benefits of ASM can be important for more complex robotic systems, such as industrial robots with 6 or 7 DOF. The results achieved by ASM can be easily written in the form that the N-E recursive procedure delivers, but vice versa is very hard.

Path planning and re-planning for serial 6 degree of freedom (DOF) robotic systems is challenging due to the complex kinematic structure which reflects in the direct and inverse kinematic solutions. Industrial robots can move either in joint space, which use direct kinematic solver or Cartesian space which use the inverse kinematic solver. The complexity in robotics comes from the inverse kinematics, when the robot is moving in the Cartesian space. In that case singularity conditions can occur. The singularity regions for the Fanuc LR Mate 200iC robot have been calculated by finding the determinant of the robot's Jacobian matrix. The recursive Newton-Euler method and the Vector multiplication method are used for the Jacobian matrix generation and validation. The visual representations of the singularity regions are done using the MTALAB tools, which will help process designers to develop valid robot trajectories and optimal layout designs. The validation of the results is done by using the Fanuc LR Mate 200iC robot available in our lab. For each singularity position the Teach Pendant showed the error and the Robot couldn't move. By visualizing the singularity regions location in advance, the manufacturing layout design will be faster and more accurate.

Trajectory planning for serial 6 degree of freedom (DOF) machinery systems is demanding due to complex kinematic structure which affects the machinery tool fame, position, orientation and singularity. These three characteristics represent the key elements for production planning and layout design of the manufacturing systems. Both, simple and complex machine trajectory is defined as series of connected points in 3D space. Each point is defined with its position and orientation related to the machine's base frames. To visualize the machine's reachable space, the work envelope is calculated and graphically presented as very well known machine's property. A methodology to predetermine regions of feasible tool orientation (work window) is analytically and graphically presented. The work envelope boundary is generated using the filtering points algorithm, while work window is generated using either empirical or analytical methods. The singularity regions are calculated by finding the determinant of the reconfigurable Jacobian matrix. These three tool path characteristics represent three different spaces which are identified both analytically and graphically and plotted in Cartesian space using MATLAB tools. The singularity regions will be represented within the workspace and work window for a single machinery kinematic structure. The KUKA KR robot family is used as a case study.

This paper provides a new design of robust fault detection for turbofan engines with adaptive controllers. The critical issue is that the adaptive controllers can depress the faulty effects such that the actual system outputs remain the pre-specified values, making the fault detection difficult. In addition, observer-based fault-detection strategies are not always reliable because the observer gain may be selected large due to the consideration of stability, robustness or performance, leading to the size of output estimation errors, which are used as fault-detection residuals, small. To solve this problem, the Total Measurable Fault Information Residual (ToMFIR) technique is adopted to detect faults in turbofan engines with adaptive controllers. To this end, a bank of systems, each corresponding to a particular fault, is formulated by reorganizing the considered uncertain engine model. Each system in the bank is first transformed into two subsystems. Then, a ToMFIR is designed for the disturbance-free subsystem to generate a fault-detection residual. In this manner, a bank of ToMFIR's is constructed to detect a specific fault source. The advantage of such a design is that all of ToMFIR's in the bank will together declare the occurrence of a single fault. This design is a ToMFIR-redundancy-based robust fault detection. Detailed design process of the ToMFIR's is presented and a turbofan engine model is simulated to verify the effectiveness of the proposed ToMFIR-based fault-detection strategy.

The aim of this paper is to highlight the importance of forming a mathematical model of Cable suspended Parallel Robot CPR (aerial robot) since only that way CPR provides precise guidance in the area. Only highly intelligent control systems based on high authentic system mathematical model can provide the realization of very complex tasks. The established mathematical model provides an opportunity to modernize CPR significantly and to make its application become much wider. © 2012 IEEE.

The purpose of this research is to implement the presented results and possibly improve the model for the future modernization autonomy and intelligent behavior of the aerial robot named Cable Suspended Parallel Robot CPR. Visionary speaking these high set goals were a strong incentive to define highly reliable kinematic and dynamic model of the CPR system which will be used for the control purposes. © 2012 IEEE.

Automated model generation and solution for motion planning and re-planning of automated systems will play an important role in the future of reconfigurable manufacturing systems. Multi-DOF kinematic structure was generated for any combination of either rotational or translational type of joints, using a novel methodology presented in this paper. This model is named n-DOF Global Kinematic Model (n-GKM). All possible kinematic structures are considered in 3D space, which is divided into eight subspaces and three planes. The planes are perpendicular to the x, y, and z axis of the kinematic structure's base frame. The intersections of the three planes divide 3D space into eight subspaces. The kinematic structure generated using the proposed methodology belongs to any of the three surfaces or to any of the eight subspaces. This kinematic structure can be implemented for any robotic system or CNC machine. A methodology for model generation is presented and demonstrated with 2-DOF Global Kinematic Model (2-GKM) case study.

Simulation tools need to be developed to support modeling and product/process analysis activities for material deposition processes. The long term research goal is to develop a set of virtual modelling tools to support advanced tool motions and process planning strategies for this application. The goal of this research is to develop a reconfigurable robotic platform that can adapt to variable product size characteristics, and alternative deposition strategies while respecting the unique process-related constraints for 2 ½ axis and 2 ½ axis + 2 axis tool paths. A variety of topologies are investigated. For the selected system, a parametric kinematic, dynamic and control model is developed for configurations of the basic platform. Results for kinematic and dynamic reconfigurations of this base platform are then presented. To simulate the process realistically using existing tools, a methodology is developed to illustrate material deposition in conjunction with the tool motions for a 3 degree of freedom (2 degree of freedom planar robot with a translational axis) configuration.