With the spread of intelligent robotic agents, numerous robotic platforms have been developed and disseminated in an open-source manner to allow replication by others in robotics education and research [7], [8]. Even though considerable progress has already been made in the field, most of the related work has focused on ground-based, stationary, or humanlike robotic devices [7], [9]–[10][11]. While they are certainly a reasonable choice in many educational and research scenarios, such robots are often heavy, expensive, hard to replicate, or have limited mobility.

Such limitations can be overcome by indoor aerial platforms, which have in the recent years received a lot of attention. The most popular choice of such systems are quadrotors that have been developed as fully autonomous indoor, aerial robotic platforms [12]–[13][14]. Other studies have focused on indoor robotic airships. Skye [5] is a spherical omnidirectional blimp actuated by 4 rotors and equipped with a high resolution camera unit. It was intended for entertainment and interaction in large indoor and outdoor venues as the platform itself is quite large, with a diameter of 2.7 m. Another entertainment-oriented indoor airship platform is the Blimpduino [15], which features an Arduino-based control board that allows communication and basic control through a mobile app. The blimpduino came at a very affordable price of 90 USD, although it is not available for purchase anymore at the time of writing. A notable example of an autonomous indoor blimp is also the GT-MAB [16], one of the smallest autonomous indoor LTA platforms designed for human-robot interaction and autonomy studies. In [17], the GT-MAB was demonstrated in a human following and gesture recognition scheme, paving the road for flying airship companions.

Some research has also focused on human interaction with rotorcraft, where work was mainly based on one-directional communication through gesture recognition. In [18], the authors presented an agent capable of full-pose person tracking and accepting simple gestural commands. Authors of [19] expanded this concept by developing a gesture-based interface for communicating with teams of quadrotors. In [20], the authors reversed the information flow and examined the communication of UAV intent to a human user through motion. Regarding rotorcraft, only the visual mode of interaction was considered in human robot interaction research because these platforms are generally too loud for auditory communication and too dangerous for tactile communication. LTA vehicles, on the other hand, can be silent and harmless to the user, provided that an appropriate lifting gas is chosen.

The miniaturisation and democratisation of electronic components (access to sophisticated technology has become more accessible to more people) has allowed for progressively smaller and more low-cost designs of indoor airships, which have since become relevant for both robotics education and research. Initial studies have focused mainly on airship control and navigation, utilising the aerodynamic envelope shapes of their larger, outdoor airship counterparts. In [21], the authors presented an early indoor blimp system and studied visual servoing techniques. In [22], a dynamic airship model was developed and successfully applied in an indoor testing environment. Other examples that make use of the classic blimp envelope shapes include developments in blimp autonomy and navigation as described in [23], [24]. But all these studies have not focused on the feasibility of the robotic airship platforms, have not examined the permeability and applicability of different materials, the yearly helium losses, and the projected costs and none of these studies has proposed an open-source, platform that can be used for both robotics education and research.

References

[7] S. S. Srinivasa, P. Lancaster, J. Michalove, M. Schmittle, C. Summers, M. Rockett, et al., "MuSHR: A low-cost open-source robotic racecar for education and research", arXiv:1908.08031, 2019, [online] Available: http://arxiv.org/abs/1908.08031.

[8] G. P. Kontoudis, M. V. Liarokapis, A. G. Zisimatos, C. I. Mavrogiannis and K. J. Kyriakopoulos, "Open-source anthropomorphic underactuated robot hands with a selectively lockable differential mechanism: Towards affordable prostheses", Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst. (IROS), pp. 5857-5862, Sep. 2015.

[9] M. Lapeyre, P. Rouanet, J. Grizou, S. N’Guyen, A. Le Falher, F. Depraetre, et al., "Poppy: Open source 3D printed robot for experiments in developmental robotics", Proc. 4th Int. Conf. Develop. Learn. Epigenetic Robot., pp. 173-174, Oct. 2014.

[10] M. Kerzel, E. Strahl, S. Magg, N. Navarro-Guerrero, S. Heinrich and S. Wermter, "NICO—Neuro-inspired companion: A developmental humanoid robot platform for multimodal interaction", Proc. 26th IEEE Int. Symp. Robot Hum. Interact. Commun. (RO-MAN), pp. 113-120, Aug./Sep. 2017.

[11] F. Arvin, J. Espinosa, B. Bird, A. West, S. Watson and B. Lennox, "Mona: An affordable open-source mobile robot for education and research", J. Intell. Robotic Syst., vol. 94, no. 3, pp. 761-775, Jun. 2019.

[12] J. P. How, B. Behihke, A. Frank, D. Dale and J. Vian, "Real-time indoor autonomous vehicle test environment", IEEE Control Syst. Mag., vol. 28, no. 2, pp. 51-64, Apr. 2008.

[13] S. Grzonka, G. Grisetti and W. Burgard, "A fully autonomous indoor quadrotor", IEEE Trans. Robot., vol. 28, no. 1, pp. 90-100, Feb. 2012.

[14] T. Tomic, K. Schmid, P. Lutz, A. Domel, M. Kassecker, E. Mair, et al., "Toward a fully autonomous UAV: Research platform for indoor and outdoor urban search and rescue", IEEE Robot. Autom. Mag., vol. 19, no. 3, pp. 46-56, Sep. 2012.

[15] Blimpduino 2.0 Kit, Jan. 2020, [online] Available: https://www.jjrobots.com/blimpduino-2/.

[16] S. Cho, V. Mishra, Q. Tao, P. Vamell, M. King-Smith, A. Muni, et al., "Autopilot design for a class of miniature autonomous blimps", Proc. IEEE Conf. Control Technol. Appl. (CCTA), pp. 841-846, Aug. 2017, [online] Available: http://ieeexplore.ieee.org/document/8062564/.

[17] N. Yao, E. Anaya, Q. Tao, S. Cho, H. Zheng and F. Zhang, "Monocular vision-based human following on miniature robotic blimp", Proc. IEEE Int. Conf. Robot. Autom. (ICRA), pp. 3244-3249, May 2017.

[18] T. Naseer, J. Sturm and D. Cremers, "FollowMe: Person following and gesture recognition with a quadrocopter", Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst., pp. 624-630, Nov. 2013.

[19] V. M. Monajjemi, J. Wawerla, R. Vaughan and G. Mori, "HRI in the sky: Creating and commanding teams of UAVs with a vision-mediated gestural interface", Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst., pp. 617-623, Nov. 2013.

[20] D. Szafir, B. Mutlu and T. Fong, "Communication of intent in assistive free flyers", Proc. ACM/IEEE Int. Conf. Hum.-Robot Interact. (HRI), vol. 2, no. 1, pp. 358-365, Mar. 2014, [online] Available: http://dl.acm.org/citation.cfm?doid=2559636.2559672.

[21] H. Zhang and J. P. Ostrowski, "Visual servoing with dynamics: Control of an unmanned blimp", Proc. IEEE Int. Conf. Robot. Autom., vol. 1, pp. 618-623, May 1999, [online] Available: http://ieeexplore.ieee.org/lpdocs/epic03/wrapper.htm?arnumber=770044.

[22] J.-C. Zufferey, A. Guanella, A. Beyeler and D. Floreano, "Flying over the reality gap: From simulated to real indoor airships", Auto. Robots, vol. 21, no. 3, pp. 243-254, Nov. 2006.

[23] P. González, W. Burgard, R. Sanz Domínguez and J. López Fernández, "Developing a low-cost autonomous indoor blimp", J. Phys. Agents, vol. 3, no. 1, pp. 43-52, 2009.

[24] J. Muller, A. Rottmann, L. M. Reindl and W. Burgard, "A probabilistic sonar sensor model for robust localization of a small-size blimp in indoor environments using a particle filter", Proc. IEEE Int. Conf. Robot. Autom., pp. 3589-3594, May 2009.