The advent of rapid prototyping & manufacturing techniques represents a major breakthrough in production engineering. This paper is concerned with the software system aspects of the selective laser sintering (SL...The advent of rapid prototyping & manufacturing techniques represents a major breakthrough in production engineering. This paper is concerned with the software system aspects of the selective laser sintering (SLS),i.e.the issues that deal with an external geometric CAD model to automatically control the physical layering fabrication process as directly as possible ,regardless of the source of the model. The general issues are described and some key methods are given in this paper.展开更多
This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct contro...This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct control of six joints. The original structure of the PUMA robot is retained. The hardware of the new controller includes such in-house designed parts as pulse width modulation (PWM) amplifiers, digital and analog controllers, I/O cards, signal conditioner cards, and 16-bit A/D and D/A boards. An Intel Pentium IV industrial computer is used as the central controller. The control software is implemented using VC++ programming language. The trajectory tracking performance of all six joints is tested at varying velocities. Experimental results show that it is feasible to implement the suggested open architecture platform for PUMA 500 series robots through the software routines running on a PC. By assembling controller from off-the-shell hardware and software components, the benefits of reduced and improved robustness have been realized.展开更多
Knowledge acquisition has always been the bottleneck of artificial intelligence. It is the critical point in product family design. Here a knowledge acquisition method was introduced based on scenario model and reposi...Knowledge acquisition has always been the bottleneck of artificial intelligence. It is the critical point in product family design. Here a knowledge acquisition method was introduced based on scenario model and repository grid and attribute ordering table technology. This method acquired knowledge through providing product design cases to expert, and recording the means and knowledge used by the expert to describe and resolve problems. It used object to express design entity, used scenario to describe the design process, used Event-Condition-Action（ECA） nile to drive design process, and with the help of repository grid and attribute ordering table technology to acquire design knowledge. It＇ s a good way to capture explicit and implicit knowledge. And its validity is proved with respective examples.展开更多
The paper discusses the importance of computer as a supporting approach in architecture. This approach is expected to foster the students＇ design skills in design studios. The approach is an educational tool for tuto...The paper discusses the importance of computer as a supporting approach in architecture. This approach is expected to foster the students＇ design skills in design studios. The approach is an educational tool for tutors that could guide the students and increase their creativity in their design. It considers the concepts and the practice of digital architectural design that influence architectural education. The approach is a catalyst for creativity, experimentation, critical thinking and the sustained growth of creative communities. The core of design studio is the notions, methods and skills of digital architectural design. The instruments used for this research was an investigation that made for the work of the fourth year students designs at the architectural department at University of Jordan, by testing design process and product of students＇ work： first using manual skills, and then using computer-aided programs. The results revealed that the computer-based design approach was able to foster students＇ design skills as well as to develop their creativity in design. Ninety-one percent of 44 students were found improved in design process using computer-based approach that depends on computer programs. This was done in design studio by improving students＇ way of thinking, developing their abilities to direct their own learning and pushing them for new definitions in developing their future work.展开更多
The strength and stiffness contribution of infill masonry is generally ignored in the design, due to the uncertainty in the strength properties of masonry, separation of infill from frame, low tensile strength, brittl...The strength and stiffness contribution of infill masonry is generally ignored in the design, due to the uncertainty in the strength properties of masonry, separation of infill from frame, low tensile strength, brittle characteristics of masonry walls, less out of plane strength and stiffness, etc.. They are considered as nonstructural elements which is reasonable for the frames under gravity loads but it is not true for the frames under seismic loads. Contained masonry as infill in RC （reinforced concrete） frames provides better contact at the interface and a higher out of plane strength and stiffness. Considering the seismic action on the frames which are likely to be subjected to in-plane as well as out of plane shaking, a research work has been carried out by the authors to investigate the seismic performance of RC frames with and without contained masonry infill panels using FE （finite element） computer program （ANSYS-Ver. l 1） and experimentally using the tri-axial shake table to evaluate the methods proposed in IS-1893-2002 to calculate the fundamental natural frequency. The RC frames were designed and detailed as per IS （Indian Standard） specifications such as IS 456-2000, IS 1893-2002 and IS 13920-1993. Based on the experimental and analytical investigations, the contained masonry infill panels significantly affect the seismic load resisting characteristics of the RC frames. The IS 1893-2002 formulation does not predict the values and hence the recommendation needs to be validated with experimental results.展开更多
文摘The advent of rapid prototyping & manufacturing techniques represents a major breakthrough in production engineering. This paper is concerned with the software system aspects of the selective laser sintering (SLS),i.e.the issues that deal with an external geometric CAD model to automatically control the physical layering fabrication process as directly as possible ,regardless of the source of the model. The general issues are described and some key methods are given in this paper.
文摘This paper describes the replacement of a controller for a programmable universal machine for assembly (PUMA) 512 robot with a newly designed PC based (open architecture) controller employing a real-time direct control of six joints. The original structure of the PUMA robot is retained. The hardware of the new controller includes such in-house designed parts as pulse width modulation (PWM) amplifiers, digital and analog controllers, I/O cards, signal conditioner cards, and 16-bit A/D and D/A boards. An Intel Pentium IV industrial computer is used as the central controller. The control software is implemented using VC++ programming language. The trajectory tracking performance of all six joints is tested at varying velocities. Experimental results show that it is feasible to implement the suggested open architecture platform for PUMA 500 series robots through the software routines running on a PC. By assembling controller from off-the-shell hardware and software components, the benefits of reduced and improved robustness have been realized.
文摘Knowledge acquisition has always been the bottleneck of artificial intelligence. It is the critical point in product family design. Here a knowledge acquisition method was introduced based on scenario model and repository grid and attribute ordering table technology. This method acquired knowledge through providing product design cases to expert, and recording the means and knowledge used by the expert to describe and resolve problems. It used object to express design entity, used scenario to describe the design process, used Event-Condition-Action（ECA） nile to drive design process, and with the help of repository grid and attribute ordering table technology to acquire design knowledge. It＇ s a good way to capture explicit and implicit knowledge. And its validity is proved with respective examples.
文摘The paper discusses the importance of computer as a supporting approach in architecture. This approach is expected to foster the students＇ design skills in design studios. The approach is an educational tool for tutors that could guide the students and increase their creativity in their design. It considers the concepts and the practice of digital architectural design that influence architectural education. The approach is a catalyst for creativity, experimentation, critical thinking and the sustained growth of creative communities. The core of design studio is the notions, methods and skills of digital architectural design. The instruments used for this research was an investigation that made for the work of the fourth year students designs at the architectural department at University of Jordan, by testing design process and product of students＇ work： first using manual skills, and then using computer-aided programs. The results revealed that the computer-based design approach was able to foster students＇ design skills as well as to develop their creativity in design. Ninety-one percent of 44 students were found improved in design process using computer-based approach that depends on computer programs. This was done in design studio by improving students＇ way of thinking, developing their abilities to direct their own learning and pushing them for new definitions in developing their future work.
文摘The strength and stiffness contribution of infill masonry is generally ignored in the design, due to the uncertainty in the strength properties of masonry, separation of infill from frame, low tensile strength, brittle characteristics of masonry walls, less out of plane strength and stiffness, etc.. They are considered as nonstructural elements which is reasonable for the frames under gravity loads but it is not true for the frames under seismic loads. Contained masonry as infill in RC （reinforced concrete） frames provides better contact at the interface and a higher out of plane strength and stiffness. Considering the seismic action on the frames which are likely to be subjected to in-plane as well as out of plane shaking, a research work has been carried out by the authors to investigate the seismic performance of RC frames with and without contained masonry infill panels using FE （finite element） computer program （ANSYS-Ver. l 1） and experimentally using the tri-axial shake table to evaluate the methods proposed in IS-1893-2002 to calculate the fundamental natural frequency. The RC frames were designed and detailed as per IS （Indian Standard） specifications such as IS 456-2000, IS 1893-2002 and IS 13920-1993. Based on the experimental and analytical investigations, the contained masonry infill panels significantly affect the seismic load resisting characteristics of the RC frames. The IS 1893-2002 formulation does not predict the values and hence the recommendation needs to be validated with experimental results.
