Abstract: How to detect and handle force and geometric obstacles is one of the major problems for excavating-robots in difficult working conditions. In this paper, methods for an excavating-robot to semi-autonomously avoid obstacles which are not predicted along the pre-planned paths for digging and transport are presented. During the digging process, a fuzzy semi-autonomous controller takes the information of the pressures of cylinders ,their derivatives and angular displacements as input to the fuzzy control rules and generates fuzzy output to the excavating-robot handling the force obstacle. And during the transport process, a "virtual resistance force region" in front of a geometric obstacle is invented and an impedance control is specified to produce the desired behavior to avoid the obstacle. Experiments show the proposed methods are feasible.