Cable-suspended load lifting by a quadrotor UAV: hybrid model, trajectory generation, and control
- 1.6k Downloads
In the last years, autonomous aerial vehicles have become promising mobile robotic platforms capable of manipulating external objects. In particular, quadrotors, rotorcrafts with four propellers, have been used for aerial transportation of cable-suspended loads. A critical step before transporting a payload is the lift maneuver. However, the analysis and planning of this maneuver have received a little attention in the literature so far. In this work, we decompose the cable-suspended load lifting into three simpler discrete states or modes: Setup, Pull, and Raise. Each of these states represents the dynamics of the quadrotor-load system at particular regimes during the maneuver. Furthermore, we define a hybrid system based on these states and show that it is a differentially-flat hybrid system. Exploiting this property, we generate a trajectory by using a series of waypoints associated with each mode. We design a nonlinear hybrid controller to track this trajectory and therefore execute the lift maneuver. We verify the proposed approach by carrying out experiments on an actual quadrotor with a cable-suspended load.
KeywordsAerial transportation Lift maneuver Hybrid systems Differential flatness Trajectory generation
This work was supported in part by the Army Research Lab Micro Autonomous Systems and Technology Collaborative Alliance (ARL MAST-CTA #W911NF-08-2-0004). We would like to thank the Ecuadorian scholarship program administrated by the Secretaría de Educación Superior, Ciencia, Tecnología e Innovación (SENESCYT) for providing part of the financial support for P. J. Cruz. We gratefully acknowledge Prof. Meeko Oishi from UNM for numerous discussions and her invaluable feedback about the hybrid model. Special thanks to Christoph Hintz for his help in recording the experimental tests.
Supplementary material 1 (wmv 134748 KB)
- Achtelik, M., Achtelik, M., Weiss, S., & Siegwart, R. (2011). Onboard IMU and monocular vision based control for MAVs in unknown in- and outdoor environments. In IEEE international conference on robotics and automation (ICRA), (pp. 3056–3063).Google Scholar
- Ascending Technologies (2010). AscTec Hummingbird with AutoPilot User’s Manual. http://ugradrobotics.wikispaces.com/file/view/AscTec_AutoPilot_manual_v1.0_small.pdf. Accessed Jan 2016.
- Ascending Technologies (2015). AscTec Hummingbird. http://wiki.asctec.de/display/AR/AscTec+Hummingbird. Accessed Jan 2016.
- Beloti Pizetta, I., Santos Brandão, A., & Sarcinelli-Filho, M. (2015). Modelling and control of a PVTOL quadrotor carrying a suspended load. In international conference on unmanned aircraft systems (ICUAS), (pp. 444–450).Google Scholar
- Construction Safety Association (2000). Helicopter lifting. Ontario: Safety Guidelines for Construction.Google Scholar
- Cruz, P. J. & Fierro, R. (2014). Autonomous lift of a cable-suspended load by an unmanned aerial robot. In IEEE conference on control applications (CCA), (pp. 802–807).Google Scholar
- Cruz, P. J., Oishi, M., & Fierro, R. (2015). Lift of a cable-suspended load by a quadrotor: A hybrid system approach. In American control conference(ACC), (pp. 1887–1892).Google Scholar
- Faust, A., Palunko, I., Cruz, P., Fierro, R., & Tapia, L. (2014). Automated aerial suspended cargo delivery through reinforcement learning. Artificial Intelligence (In press) Google Scholar
- Ghadiok, V., Goldin, J., & Ren, W. (2011). Autonomous indoor aerial gripping using a quadrotor. In IEEE/RSJ international conference on intelligent robots and systems (IROS), (pp. 4645–4651).Google Scholar
- Goodarzi, F. & Lee, T. (2015). Dynamics and control of quadrotor UAVs transporting a rigid body connected via flexible cables. In American control conference (ACC), (pp. 4677–4682).Google Scholar
- Gurdan, D., Stumpf, J., Achtelik, M., Doth, K.-M., Hirzinger, G., & Rus, D. (2007). Energy-efficient autonomous four-rotor flying robot controlled at 1 kHz. In IEEE international conference on robotics and automation (ICRA), (pp. 361–366).Google Scholar
- Hehn, M. & D’Andrea, R. (2011). Quadrocopter trajectory generation and control. In Proceedings of the IFAC world congress, (pp. 1485–1491).Google Scholar
- Lewis, F. L., Vrabie, D., & Syrmos, V. L. (2012). Optimal control (3rd ed.). Hoboken: WileyGoogle Scholar
- Lygeros, J., Sastry, S., & Tomlin, C. (2012). Hybrid systems: Foundations, advanced topics and applications. Department of Electrical Engineering and Computer Sciences: University of California, Berkeley. (in preparation).Google Scholar
- Marhes Lab (2016). Cable-Suspended Load Lifting by a Quadrotor UAV. https://www.youtube.com/watch?v=rHtw80dqcGk. Accessed June 2016. YouTube Channel.
- Mellinger, D. & Kumar, V. (2011). Minimum snap trajectory generation and control for quadrotors. In IEEE international conference on robotics and automation (ICRA), (pp. 2520–2525).Google Scholar
- National Instruments (2016a). LabVIEW real-time module. http://www.ni.com/labview/realtime/. Accessed Jan 2016.
- National Instruments (2016b). NI CompactRIO. http://www.ni.com/compactrio/. Accessed Jan 2016.
- Orsag, M., Korpela, C., Bogdan, S., & Oh, P. (2014). Valve turning using a dual-arm aerial manipulator. In International conference on unmanned aircraft systems (ICUAS), (pp. 836–841).Google Scholar
- Spica, R., Franchi, A., Oriolo, G., Bulthoff, H., & Giordano, P. (2012). Aerial grasping of a moving target with a quadrotor UAV. In IEEE/RSJ international conference on intelligent robots and systems (IROS), (pp. 4985–4992).Google Scholar
- Sreenath, K., Michael, N., & Kumar, V. (2013). Trajectory generation and control of a quadrotor with a cable-suspended load—a differentially-flat hybrid system. In IEEE international conference on robotics and automation (ICRA), (pp. 4888–4895).Google Scholar
- Stengel, R. (1994). Optimal Control and Estimation. Dover Books on Advanced Mathematics. New York: Dover Publications.Google Scholar
- Tang, S. & Kumar, V. (2015). Mixed integer quadratic program trajectory generation for a quadrotor with a cable-suspended payload. In IEEE international Conference on Robotics and Automation (ICRA), (pp. 2216–2222).Google Scholar
- UK Civil Aviation Authority (2006). Helicopter external load operations (4th ed.). Safety Regulation Group.Google Scholar
- van Nieuwstadt, M., Rathinam, M., & Murray, R. (1994). Differential flatness and absolute equivalence. In IEEE conference on decision and control (CDC), (Vol. 1, pp. 326–332).Google Scholar