In this paper, we employ a hybrid feedback control strategy to globally asymptotically stabilize a setpoint on a smooth compact manifold without boundary satisfying the following: there exists a finite maximal atlas such that the desired setpoint belongs to each chart of the atlas. The proposed hybrid controller includes a proportional-derivative (PD) action during flows and, at jumps, uses hysteresis to switch between local coordinate charts to stabilize the desired setpoint robustly with respect to exogenous disturbances. We show that the proposed controller can be used for attitude stabilization of a rigid body and we illustrate the behavior of the closed-loop system via simulation results.
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Assessment of internal and external disturbances on the fuzzy-based thermal control of a sub-scaled building testbed
This experimental study follows on our previous work on the development of robust fuzzy-based thermal control strategies of a multi-room sub-scaled building testbed. In the present analysis, the focus is placed on testing the robustness of the fuzzy controller under internal and external disturbances, as it deals with maintaining specific setpoint values of room temperatures. The testbed has eight rooms, distributed on two floors, with a cooling unit that supplies cool air to each room, and eight 40 W light bulbs serving as heat sources. T-type thermocouples gather the temperature data, and eight dampers deliver the airflow. The controller uses information about the difference between setpoint and actual temperatures, their derivative, and their cumulative integral. The fuzzy sets and if-then rules are built based on experimental data, and a Mamdani inference method is used to provide the inputs to the actuators. Results from experimental tests show that the fuzzy control strategy can handle the different types of disturbances while maintaining the room setpoints.
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- Award ID(s):
- 2112554
- PAR ID:
- 10525817
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Journal of Physics: Conference Series
- Volume:
- 2766
- Issue:
- 1
- ISSN:
- 1742-6588
- Page Range / eLocation ID:
- 012103
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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