The WALK mode is one of the most common navigation interfaces for 3D virtual environments. However, due to the limited view angle and low frame rate, users are often blocked by obstacles when they navigate in a cluttered virtual scene with such a mode. Intelligent 3D navigation interfaces with assisting mechanisms, such as motion planning methods or virtual force fields, have been proposed in the literature to improve navigation efficiency. Nevertheless, the applicability of these methods is subject to individual discrepancy, and the control parameters of these methods are usually determined by empirical means. In this paper, we propose an intelligent navigation interface with a personalizable assisting mechanism. We have designed two methods, simulation experiment and dynamic adjustment, to find the best control parameters for composing artificial forces for an individual in an off-line and on-line manner, respectively. The simulation experiment method searches for the optimal contro...