Soft Inflatable Robotic Sleeves for Actuation and Shock Absorption

As robots are becoming compact and autonomous, they are more frequently deployed to disaster sites for various activities, such as search, rescue, and transportation. However, hazardous environments in disaster areas (e.g. cluttered, unstructured and highly constrained spaces) bring harm not only to humans but also to robots. Without a mechanism of physical protection, robots can be vulnerable to ongoing and potential dangers, such as piles of debris and falling objects. In order to prevent the system failure from physical damages, we proposed a shock absorption (or reduction) mechanism using soft inflatable sleeves [1]. The proposed inflatable sleeve can be actively inflated and deflated depending on the surroundings, not degrading the mobility of the robot. For example, the robot can inflate itself when falling from height but deflate when passing through narrow and low pathways. Heat sealable materials are used for the proposed sleeves. Depending on the sealing patterns, the inflated shape of the sleeve can make different shapes. In order to make various patterns, a three-axis translation stage, equipped with a roller-tip with a heating element was built, shown in Fig. 1, which is similar to the system described in [2]. This system facilitates repetitive work, sealing complex patterns, and allows rapid fabrication. Also, it enables the tip to maintain uniform normal force to the materials during fabrication. Using this system, multi-chambered inflatable structures can be made with various heat sealable materials.