Point-to-point control of a gantry crane: A combined flatness and IDA-PBC strategy

We have designed a controller based on gain-scheduling feedback to move a load from point to point within one oscillation cycle and without inducing large swings. The settling time of the system is taken to be equal to the period of oscillation of the load. This criterion enables us to calculate the controller feedback gains for varying load weight and cable length. First, we designed the controller for gantry cranes and then extended it to tower cranes by considering the coupling between the translational and rotational motions. Numerical simulations show that the controller is effective for reducing load oscillations and transferring the load in a reasonable time compared with that of optimal control. To experimentally validate the theory, we had to compensate for friction. To this end, we estimated the friction, then applied an opposite control action to cancel it. To estimate the friction force, we assumed a mathematical model, then we estimated the model coefficients using an off-line identification technique, the least-squares method. First, the process of identification was applied to a theoretical model of a dc motor with known friction coefficients. From this example, some guidelines and rules were deduced for the choice of the least-squares parameters. Then, the friction coefficients of the gantry crane model were estimated and validated.

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Motion profile planning of repetitive point-to-point control for maximum energy conversion efficiency under acceleration conditions

Mechatronics ◽

10.1016/0957-4158(96)00012-8 ◽

1996 ◽

Vol 6 (6) ◽

pp. 649-663 ◽

Cited By ~ 54

Author(s):

J.S. Park

Keyword(s):

Energy Conversion ◽

Conversion Efficiency ◽

Energy Conversion Efficiency ◽

Maximum Energy ◽

Point Control ◽

Point To Point ◽

Motion Profile

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Modeling and Mechanical Design of an Active-Caster Omnidirectional Mechanism with a Ball Transmission

Journal of Robotics and Mechatronics ◽

10.20965/jrm.2018.p0910 ◽

2018 ◽

Vol 30 (6) ◽

pp. 910-919 ◽

Cited By ~ 1

Author(s):

Kosuke Kato ◽

◽

Masayoshi Wada

Keyword(s):

Power Distribution ◽

Control Function ◽

Mechanical Design ◽

Computer Control ◽

Single Layer ◽

Control Algorithms ◽

Angle Sensor ◽

Simple Motor ◽

Point Control ◽

Point To Point

This paper presents kinematic and static analyses of an active-caster robotic drive with a single-layer ball transmission (ACROBAT-S). On the basis of the analyses, a single-wheel prototype is designed, and fundamental experiments using the prototype are conducted. The proposed ACROBAT-S includes a ball transmission that transmits power to a wheel axis and steering axis of an active-caster wheel in an appropriate ratio to produce so-called “caster motion.” The power distribution is realized mechanically rather than by complicated computer control algorithms. Therefore, the angle sensor for detecting the wheel orientation, and the control calculations for coordinated control of the wheel and steering motors of a conventional system are eliminated. Thus, the proposed mechanical design, which transfers a part of the control function to the mechanism, contributes to simplifying the overall control system. The results of the analyses and experiments with a prototype confirm that the proposed active-caster mechanism, ACROBAT-S, can realize the expected omnidirectional motion with simple motor control, such as Point-To-Point control.

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A Hybrid Scheme Motion Controller by Sliding Mode and Two-Degree-of-Freedom Controls to Minimize the Chattering

Mathematical Problems in Engineering ◽

10.1155/2014/583280 ◽

2014 ◽

Vol 2014 ◽

pp. 1-10

Author(s):

Chiu-Keng Lai

Keyword(s):

Sliding Mode ◽

Gain Control ◽

High Gain ◽

Degree Of Freedom ◽

Servo Motor ◽

Motion Controller ◽

Point Control ◽

High Gain Control ◽

Point To Point ◽

Two Degree Of Freedom

Sliding mode control (SMC) is rapped for the chattering due to high gain control. However, high gain control causes the system robust. For developing a system with robustness of SMC, a servo motor motion controller combining the two-degree-of-freedom (2DOF) system and SMC is proposed. The discussed motion type is point-to-point control with the constraint of trapezoid velocity profile. SMC is designed to guide the motor motion to follow a predefined trail, and the inner 2DOF system is used to compensate the deterioration due to the adoption of load observer. The proposed hybrid system is realized on a PC-based motion controller, and the validness is verified by simulation and experimental results.

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Point-to-Point Positioning of Flexible Structures Using a Time Domain LQ Smoothness Constraint

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2897363 ◽

1992 ◽

Vol 114 (3) ◽

pp. 416-421 ◽

Cited By ~ 2

Author(s):

S. P. Bhat ◽

D. K. Miu

Keyword(s):

Time Domain ◽

Finite Time ◽

Flexible Structures ◽

Control Input ◽

Time Control ◽

Smoothness Constraint ◽

Point Control ◽

Point To Point ◽

The Time Domain ◽

Different Order

An analytical procedure to implement optimal smoothing of the finite-time control waveform for point-to-point control problem is presented, which minimizes an optimality constraint consisting of a linear combination of the quadratic norms of its time derivatives. It is shown that the resulting control input is essentially the minimum norm solution augmented to satisfy some additional continuity requirements in the time domain. Application of the proposed technique to finite-time maneuvering of flexible structures is experimentally demonstrated and performances are compared using control torques evaluated based on different order of the smoothness constraint and order of the truncated plant model.

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