As a novel type of robot, soft robots are used in various subtle scenes. Buoyancy materials used in small deep-sea soft robots need to have characteristics of low density and certain flexibility. Thus, in order to adapt the flexible buoyancy material (FBM) underwater equipment to the complex deep sea environment, hollow glass microspheres (HGMs) are used as fillers and silicone rubber (SR) as matrix to prepare FBM. The main properties, such as density, tensile strength, elastic modulus, hardness and water absorption are tested and analyzed to make the preparation of FBMs serialized. Scanning electron microscope (SEM) is used for morphological observations, which can distinguish the bubbles and broken HGMs in FBMs. Moreover, digital image processing (DIP) method is used to determine the content of the impurity phase in the material. Then, the influences of the impurity phase on the properties of the material are also studied. In addition, the reason of hardness change is analyzed by micro element simulation method. Results show that the performance of FBMs is relatively balanced when the mass fraction of HGM is 20%. FBMs can be used as structural material or buoyancy material of small underwater soft robots for tests and applications.

作为一种新型的机器人，软机器人用于各种微妙的场景。小型深海软机器人中使用的浮力材料需要具有低密度和一定柔韧性的特征。因此，为了使柔性浮力材料（FBM）水下设备适应复杂的深海环境，中空玻璃微球（HGM）被用作填充物，硅橡胶（SR）被用作基质来制备FBM。测试和分析了诸如密度，抗张强度，弹性模量，硬度和吸水率等主要性能，从而使FBMs的制备系列化。扫描电子显微镜（SEM）用于形态学观察，可以分辨出FBM中的气泡和破碎的HGM。此外，使用数字图像处理（DIP）方法确定材料中杂质相的含量。然后，还研究了杂质相对材料性能的影响。另外，通过微观模拟方法分析了硬度变化的原因。结果表明，当HGM的质量分数为20％时，FBMs的性能相对平衡。FBM可用作小型水下软机器人的结构材料或浮力材料，以进行测试和应用。