A landing mechanism to an asteroid with soft surface is developed. It consists of three landing feet, landing legs, cardan element, damping element, equipment base, anchoring system, and so on. Static structural analysis and modal analysis are carried out to check the strength and natural frequency of the landing mechanism with FEA. Testing platform for the anchoring system is introduced, and then the penetrating and anchoring tests of the anchoring system are carried out in different media. It shows that cohesion of the media has large influence on the penetrating and anchoring performance of the anchoring system. Landing tests of the landing mechanism with different velocities under simulated microgravity environment are carried out on the air-floating platform, and the impact accelerations are measured by the sensors on the landing mechanism. At the same time, these impact accelerations are processed by spectrum analysis to find the natural frequency of the landing mechanism. 1. Introduction Asteroids originate from the early formation of the solar system and are distributed almost everywhere of the universe. They are similar to the comets in size, mass, orbital character, formation time, and so forth. Some asteroids are rich in minerals and raw materials of the solar system’s initial formation, so they have very important scientific and economic values [1, 2]. Currently, landing on the small bodies, including asteroids and comets, is a hot spot to explore. So far, Japan has already landed and sampled successfully from an asteroid [3]. Besides, NASA has devoted lots of energy in small body landing explorations, such as NEAR spacecraft [4, 5]. At the same time, ESA has launched the Rosetta lander to explore a comet by landing on it [6]. Asteroids and comets are similar in some physical properties constraining the design of the lander as mentioned above; thus some design experiences of the comet lander are significant in guiding the design of the asteroid lander. Therefore, Rosetta lander is presented even though it is a comet lander. There are many approaches to explore the asteroids, such as observing on the ground, detecting by the orbital spacecraft [7], sampling return [8, 9], and exploring by landing on them [6, 10]. Among them, landing exploration is an efficient way to explore the asteroid. The Moon and Mars have been explored successfully by landing on them. The merits of the landing exploration are as follows: (1) landing exploration could analyze the asteroid’s media in situ; (2) landing exploration can get comprehensive data of the
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