Research And Implementation Of Feedback Force System In Bicycle Simulator

With the development of Virtual Reality, Virtual driving system and Virtual Roaming system have become the focus. But in these systems, because low accuracy level in feedback force system and long time is needed when virtual environment responses user's commands, the senses of immersion and reality are extremely low which make a bad effect on the quality of virtual driving and roaming. This paper starts from three characters of virtual reality: (Imagination,Interaction,Immersion), analyzes the problems exist in these force feedback systems, during building the bicycle dynamic, this paper brings forward a proposal to calculate the gravity center which first calculates user and bicycle's gravity centers, then calculates the unitary gravity center. In this way, the feedback force's calculation accuracy is highly improved; During predigesting the virtual environment, the paper builds a dynamic multi-resolution terrain models. In this way, response time is reduced and system's third dimension is highly improved. According to the modules of bicycle simulator feedback force system, this paper makes several researches as follows: building bicycle simulator's dynamics, building and predigesting the virtual environment, implementation of the feedback force in bicycle simulator system, and designing the dynamic plate. In this paper, the following problems are being solved:1. The feedback force has been realized in the bicycle simulator system, the sense of imagination is highly improved.2. During building the dynamics, this paper brings forward a new proposal to calculate the gravity centre which first calculates the user and bicycle's gravity centers, then calculates the unitary gravity center. According to experiment's test, this proposal is able to improve accuracy of building the dynamics and calculation of feedback force.3. Building the virtual environment with DEM data, it will supply force feedback system with terrain data.Building dynamic multi-resolution terrain models, according to the difference of user sight's distance, virtual environment displays terrain with different resolution. in this way, it reduces the response time and improves environment menu's switch speed and sense of immersion.4. Building dynamic multi-resolution terrain models, according to the difference of user sight's distance, virtual environment displays terrain with different resolution. in this way, it reduces the response time and improves environment menu's switch speed and sense of immersion.5. Designing the 3 DOF bicycle dynamic plate. With the plate, users can get different gestures during driving, it increases the realistic of virtual driving. In the same time, this paper makes several experiments to check whether the plate answers for the requirements using Adams, and experiments demonstrates that the plate satisfies the requirements of virtual riding.During designing, integrated with technologies of virtual reality, dynamics and kinematics modeling and feedback force, this paper builds a bicycle simulator system, after a series of experiments, these experiments demonstrate that bicycle simulator system satisfies all the requirements of virtual roaming.