Contact sounds represent an important subset of environmental sounds that are useful for enhancing the interaction of a user with a computer-simulated virtual reality or augmented environment. The real-time synthesis of these sounds has received much attention in the auditory display community and some convincing results have been achieved[1, 2]. This paper focuses on the modeling, analysis, and synthesis of more complex contact interactions, such as sliding, rolling and bouncing. We assume the widely adopted source-filter approach and use a modal representation of the filter component. In this paper , an explicit time-domain model of the excitation is proposed that produces promising results. The main advantages of the proposed model is that it allows a compact and versatile representation of the system, as well as an efficient synthesis scheme.