In this paper, a three-dimensional control problem is investigated in which an aerial vehicle equipped with a vision system is required to track and interact with a ground moving target. In order to guarantee the continuity of target observation, horizontal and vertical commands are designed separately under the constraints of the detection zone and vehicle dynamics. In order to realize a time-optimal trajectory as well as a smooth interaction with the target, a switched interaction algorithm is proposed, which combines an improved Rendezvous-Guidance (RG) algorithm and a Proportional Integral (PI) controller by the choice of a switching point. Moreover, simulation results are provided to demonstrate not only the effectiveness of the proposed algorithm, but also a high tolerance for detection and execution errors near the interaction point.