Abstract
In this paper, two approaches for generating deflection reduction shaping commands are proposed to reduce the transient and residual deflections of flexible systems subject to asymmetric first-order actuators. The commands are limited-state in that they consist of two positive actuations of different magnitudes and one negative actuation, similar to on-off-on commands. Standard on–off commands that are commonly used in robots, cranes, and spacecrafts can degrade the control performance of conventional input-shaped commands and cause detrimental damage resulting from large transient deflections of flexible structures due to asymmetric first-order actuators. Therefore, to cope with the performance degradation resulting from the effects of first-order actuators, an approximated closed-form solution and a numerically optimized approach for deflection reduction shaping commands are presented with an exponential function, final impulse magnitude modification of an input shaper is determined by a transient deflection constraint and a phasor vector approach. The performance assessment showed that the approximated analytical approach has an advantage in real-time control applications. The characteristics of the proposed deflection reduction shaping commands are analyzed with respect to system parameters, deflection reduction ratios, and actuator time constants. The proposed command shaping techniques are numerically evaluated using a pendulum system and are experimentally validated on a mini-bridge crane.
Highlights
Input shaped commands with standard on-off actuators have been effectively used without large transient and residual deflections of linear flexible systems such as those applied in large cranes, robot manipulators, microstages and space structures [1,2,3,4]
The control performances of the proposed input shapers are evaluated in comparison to
Two methods for the of deflectionof reduction were developed to reduce the transient andgeneration residual oscillations flexible shaping systemscommands with asymmetric first-order reduce thebytransient andlimited-state residual oscillations flexible systemsdeflection with asymmetric actuators utilizing the operations.of
Summary
Input shaped commands with standard on-off actuators have been effectively used without large transient and residual deflections of linear flexible systems such as those applied in large cranes, robot manipulators, microstages and space structures [1,2,3,4]. The objective was to develop two command-shaping approaches with the limited-state operation of asymmetric first-order actuators while reducing the transient and residual deflections of elastic modes. Many techniques have been proposed to generate input shaped commands that are time optimal [8,9,10,11], limit transient deflection [12], and limit fuel consumption [13,14] using reliable optimization algorithms. Some practical developments based on input shaping have been made by considering robustness [15], limitation of transient deflection [16], and fuel efficiency [17]. As one of the open-loop control approaches, the input shaping process is implemented by convolving a reference
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
