Thesis: S.M., Massachusetts Institute of Technology, Department of Mechanical Engineering, 2017.Cataloged from PDF version of thesis.Includes bibliographical references (pages 89-92).The ability to both fly and drive is a superpower that few robots have. This thesis describes the design and control of two miniature air-and-ground vehicles, the "Flying Monkey" and the "Flying Car." The Flying Monkey was developed to demonstrate the viability and utility of miniature air-and-ground vehicles. The final design weighs 30g yet is capable of crawling, grasping, and flying. It features a novel crawling and grasping mechanism that consists of 66 linkages yet weighs only 5.1 grams. Although the crawler is capable of only forward and backward motion, we designed a controller that uses the yaw torque of the propellers to give the Flying Monkey two degrees of freedom on the ground. In experiments we demonstrated that the Flying Monkey is able to grasp small objects, fly over obstacles, and crawl through narrow pipes. The Flying Car was designed as a swarm vehicle to test multi-robot path planning. We therefore made the Flying Car as simple and robust as possible, built a small swarm of them, and tested them in a miniature town. We present two of the first algorithms for multi-robot path planning for air-and-ground vehicles, one based on priority planning and the other based on multi-commodity network flow. Thus, by designing and testing robots, controllers, and algorithms for miniature air-and-ground vehicles, this thesis hopes to serve as a starting point for future research in this promising area of study.by Minoru Brandon Araki.S.M