Minimum-time S-curve commands for vibration-free transportation of an overhead crane with actuator limits

Jin

2022

Purpose The purpose of this paper is to propose a new acceleration/deceleration (acc/dec) algorithm for motion profiles. The motion efficiency, flexibility of the motion profiles and the residual vibration of the movement are discussed in this paper. Design/methodology/approach A dynamics model is developed to assess the residual vibration of these two kinds of motion profile. And a Simulink model is created to assess the motion efficiency and flexibility of the motion profiles with the proposed acc/dec algorithm. Findings Considering the flexibility of trigonometric motion profiles and the higher motion efficiency of S-curve motion profiles, the authors add the polynomial parts into the jerk profile of the cosine function acc/dec algorithm to hold the jerk when it reaches the maximum so that the motion efficiency can increase and decrease residual vibration at the same time. And the cyclical parameter k shows the decisive factor for the flexibility of trigonometric motion profiles. Originality/value Comparing with the traditional motion profiles, the proposed motion profiles have higher motion efficiency and excite less residual vibration. The acc/dec algorithm proposed in this paper is useful for the present motion control and servo system.

Section: Introductionmentioning

confidence: 99%

An optimized cosine jerk motion profile with higher efficiency and flexibility

Jin

2022

Proceedings of the Institution of Mechanical Engineers, Part C:

“…From the current studies as mentioned above, much work has been done to improve the lifting performance of different types of cranes by exploiting different trajectory planning methods. Most of the trajectory planning methods are developed using regular types of curves, for example, the B-Spline, 21 the S-curve, 22 the RBF, 23 the NURBS, 24 etc., and they usually have their own characteristics and are suitable for different occasions. However, none of them has been clearly proved to be optimal in the field of trajectory planning of ship lifting operation for PSKBC.…”

Section: Introductionmentioning

confidence: 99%

Performance-maximum optimization of the intelligent lifting activities for a polar ship crane through trajectory planning

Zou

Lai

et al. 2022

Knuckle boom crane (KBC) mounted on a polar ship (PS) is a maritime engineering equipment widely used in offshore activities. The working performance of a PS-mounted KBC (PSKBC) may degrade quickly if manipulated manually under extreme working conditions in polar region. To address the challenges, a performance-maximum optimization method through trajectory planning is developed to further promote the intelligently unmanned lifting processes of the PSKBC. Firstly, the dynamic model of lifting activities of the PSKBC is established using Lagrangian equation, based on which the point-to-point trajectory planning (PTP) method is developed for lifting processes. Subsequently, the PTP‐based optimization model is established to realize the minimum energy consumption and time cost of the lifting activities of the PSKBC, and the obtained optimal lifting performance is compared with the traditional S-curve method. To verify the superiority of the proposed performance-maximum optimization method, numerical simulations of the lifting activities of the PSKBC with respect to different crane loads and final lifting positions are performed. Results indicate that the PTP‐based performance-maximum optimization method for the PSKBC can perfectly achieve better performances with applicable lifting trajectories regarding various working conditions and demands.

IEEE/ASME Trans. Mechatron.

“…Interesting enough, with this work a new trajectory design and optimization paradigm is proposed: while the most of planners available in the literature have a fixed structure, e.g. based on a parametric expression of the trajectory, and the free parameters are chosen using a nonlinear optimization procedure to comply with the given constraints [25], [26], according to a philosophy that can be defined top-down, in our approach the perspective can be defined bottom-up since each specification is translated in an element of the trajectory planner and then all these basic bricks are combined together in an optimal manner. The result of this design method is the shortest S-shaped trajectory compliant with all the specifications.…”

Section: Introductionmentioning

confidence: 99%

Optimization of Generalized S-Curve Trajectories for Residual Vibration Suppression and Compliance With Kinematic Bounds

Biagiotti

Melchiorri

2021

This paper proposes a new optimization algorithm that assures the minimum possible duration of generalized S-curve trajectories compliant with kinematic limitations and capable of suppressing residual vibrations when tracked by a resonant plant. Thanks to the possibility of generating such kind of trajectories with a chain of filters, called smoothers, each one characterized by a single parameter, i.e. the duration Ti of its impulse response, the optimization process aims at minimizing the order of the trajectory, and accordingly the number of smoothers in the chain, and leads to rest-to-rest trajectories that, under the given specifications, cannot be made shorter in time. Therefore, the structure of the trajectory is not predetermined but is the outcome of the proposed algorithm together with the optimal parameters defining it. The effectiveness of the proposed approach is proven by applying the designed trajectories to an experimental setup based on a flexible link.