Virtual Product Development, Based On Force Feedback Technology

Touch is one of the most important ways for mankind to know about the environment, virtual reality will be depressed in immersion and imagination without touch feedback, and a VR merely including video and audibility is far from a perfect one. A modeling system without touch provides mouse and keypad for engineer to interact with the virtual mold in the computer, but this unnatural and humdrum interaction often makes a space in engineer and product, and makes innovation design more difficult.Based on virtual reality, the paper analyzed the principle and implements means of force feedback, proposed the VR environment with force feedback, attempted to apply force feedback in virtual product development.Virtual haptical system is a circulate feedback closed loop, including bidirectional information transfer between virtual and really environment. In the virtual force feedback equipment, force is dealt as vectors. Generally speaking, force rendering includes motion dependent, time dependent and the combine of both. In order to computer force in the virtual environment, bring out the concept of "proxy point" and "hypothetical plane". Proxy point attempts to follow the end-effector position but is constrained to be on the surface of the object. When touching an object the force can be calculated by moving the poison of proxy point towards the endeffector position without violating the surface. The general model of force feedback in virtual environment is: F=A+R(V) + S(N).FreeForm system is the VR equipment that has realized force feedback, its natural manipulate substitutes the complex computer programs, avoids the space between engineer and product, its application process feeds product development very well, accelerates the idea stream between engineer and the design, and makes it easier to invent, innovate and design. Further more, FreeForm creates a precious and changeable digital resources via substantiality and analogy interface, and makes the whole process ofdesign reflect the engineer's motion and passion, plays a vital role virtual product development.Then, the paper analyzed FreeForm's application in virtual product development. FreeForm is compatible in several data format, such as .stl, .bmp, .JP8? -igs> so it can not only be used in design flow by itself, but also be a useful assistant tool in other product development methods. In a word, FreeForm can be widely used in product concept design, converse engineering, ergonomic engineering, and rapid prototyping.In the end, the paper propounded the system frame of VPD based on force feedback, according to offering effective modeling method, effective tool supporting, and effective integration manner and design mode (corporation organization configuration), analyzed the information flow and pointed out that the haptical information plays a very important role in VPD. FreeForm adds haptical information to VDP, making VDP come to true, helps engineers innovate optically, auditively, and haptically.With the development of information technology and knowledge economy, mechanical engineering emphases on the fuzzy prophase, it is very important to model from feeling. The traditional enterprise process emphasized on practicality information feedback, pays more attention on substance form information circulation, spends much in manufacturing, and this can't feed the needs of virtual product development. In order to fit VPD's needs, the traditional business process should be reengineered.Based on FreeForm, the paper discussed three new types of business process: item-group type, service center type, and specialty union type. It showed that these new types emphasizes on custom, realizes digital information flow and the joint of different specialists, makes innovate activities optical, audible, and haptical, and can pursue dramatic achievement in enterprise benefit.