Swimming in air - miniature blimp robot
We are designing and building miniature blimp platforms to be used for aerial robotics and collective behavior research. The main advantages of blimps over other drone platforms is the excellent collision tolerance and long endurance. Our blimp robots are also propelled by fins. Miniature blimps occupy a unique functional regime that melds a number of features of aquatic and aerial locomotion, i.e., swimming in air. This affords opportunities to seek inspiration from natural systems such as fish that are exceptional at locomotion and need to cater to similar operational demands including: miniature size, buoyancy control, high manoeuvrability and passive stability. Due to the vastly different fluid conditions and design pressures, we will treat treat biological systems as an operationally emulatable platform and not as a prototype for robotic blimps.
This video demonstrates our blimp performing position hold.
During this video the only inputs given were single horizontal directions, the onboard software compensated for any drift in position. Height was adjusted as noted, being mainly kept constant by the onboard software. Partway through the video, yaw input is given during the flight (as indicated by voice over) which demonstrates the use of different fins to maintain the required position and velocity.
The ArduPilot open-source software has been modified to add support for blimps, this blimp uses that software to do autonomous position-hold, currently tested with the Vicon motion capture system as position input. All processing is done onboard, with the only required external connection being the Vicon position data input. Alternatively, it can also be flown in manual mode when no position is available. The software also streams data to the ground-station computer, which allows monitoring the battery voltage as well as directly analysing the performance of the PID loops and adjusting parameters such as the PID gains.