摘要:

AbstractThis paper presents an adaptive algorithm for solving the inverse kinematics problem for robot manipulators. The algorithm is derived using Model Reference Adaptive Control (MRAC) theory and is computationally efficient for on-line applications. The proposed scheme requires noa prioriknowledge of the kinematics of the robot if Cartesian end-effector sensing is available, and requires knowledge of only the forward kinematics if joint position sensing is used. Computer simulation results are given for the re-dundant seven DOF Robotics Research arm, and demonstrate that the proposed algorithm yields accurate joint angle trajectories for a given end-effector position/orientation trajectory.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760118

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis article addresses the problem of the development of decision support systems (DSS) for Egyptian production companies. These DSS are mainly directed toward the enhancement of the management and decisionmaking processes in these companies. Elements of the DSS are the information system formed from data banks and databases, together with optimal operation models constituting their satellites. A case study of an Egyptian production company is given, comprising the different activities of ESCO Textile Company. This selected company possesses more than 10 factories spread west of Cairo, and can be viewed as an integrated system of processes having interactions. The DSS of ESCO Company is developed, including a data bank, three databases and various operation models. Finally, a brief description of the developed system is provided, as well as a thorough assessment of its applicability.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760119

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractTWo separate models are studied for the tool tip motions during a typical machining process. One of the model is nonlinear with respect to the state variables, and the other is linear but contaminated with a time-delay effect (i.e. a differential-difference equation). First, a comparison is made between the characteristic response of these two models. Starting from the disturbed initial conditions, both models showed“oscillation damping”characteristics. Second, the question of stability is addressed, particularly for the linear time-delayed model. Two different approaches are presented: frequency domain analysis and an abstract mathematical technique. An assessment of the tolerable limitations of the imposed time lag is also conducted.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760120

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractThis paper provides a philosophical yet scientific assessment of simulation validation. It suggests that the activity of simulation validation has firm theoretical roots in falsificationism, Karl Popper’s method of scientific discovery. Popper’s falsificationist view of science holds that a theory is scientific only if it is falsifiable; that is, if it makes specific predictions whose nonoccurrence will discredit it. According to Popper, while scientific theories can be falsified, they can never be proven true or verified. If a theory agrees with real world observations, it is still only, regarded as a tentative or provisional representation of reality.Simulationists are practitioners of falsificationism when they compare the output generated by a simulation model with the output data expected from or generated by a real world system. If the simulation model output data conflict with the real world output data, the simulation model is falsified and is therefore rejected. If the simulation model output data and the real world output data are consistent with each other, the simulation model is not rejected, but neither is it accepted or“proved true”. It is provisionally accepted as“valid”because it has not been falsified.The paper compares Popper’s approach with the traditional verificationist view of the scientific method and discusses the problems of induction and demarcation. Simulation is shown to be an empirical science that attempts to establish theoretical, predictive relationships which describe a real world system.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760122

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

摘要:

AbstractA generic dynamic model for the crossflow heat exchanger suitable for process emulation is presented. The finite difference technique is used to formulate the model solution under the influence of arbitrary transient inputs in both temperature and flow. By selecting a particular application of the model, namely the tubular air prehcater of a typical boiler plant, steady-state tests can be performed to establish the nodal sensitivity of the numerical technique. Finally, transient tests on two versions of the model (constant fluid properties and lumped variable fluid properties) are conducted to investigate the validity of constant property models for accurate dynamic simulation.

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760123

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor

ISSN:0228-6203    

DOI:10.1080/02286203.1991.11760124

出版商:Taylor&Francis    

年代:1991

数据来源: Taylor