Motion Control Analysis of the Fruit-Trees Robot

The article tracks the fruit-trees robot, and analyzes the fruit-trees robot’s dual-motor control system. Based on the speed incremental PID closed-loop control algorithm of the step DC motor, the PID controller’s proportional coefficient, integral coefficient and differential coefficient is concluded. It demonstrates from the stimulations and experiments that the usage of speed incremental PID control do better at the response speed and stability than the open-loop control motor when the robot is run by a straight line on the ground at the 3000rpm.

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The Improved Design of Test Machine Linear-Velocity Closed-Loop Control Circuit

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.365-366.874 ◽

2013 ◽

Vol 365-366 ◽

pp. 874-877

Author(s):

Chang Hai Li ◽

Yuan Tao Yu ◽

Shi Yang Ma ◽

Yan Chun Liu

Keyword(s):

Pid Control ◽

Control Algorithm ◽

Response Speed ◽

Test Machine ◽

Static Error ◽

Loop Control ◽

Improved Design ◽

Value Changes ◽

The Given ◽

Control Accuracy

Incremental PID has its shortcomings: great integral truncation effect, static error and spillover affect. In the control system, the controller system is required having a quick response speed, and also a certain anti-interference ability. When adopting the improved differential PID control algorithm, only the output differential is made, instead of the given values. So, when a given value changes, the output will not change, and the controlled quantity change is usually mild, in which case the control accuracy is improved, and the system dynamic characteristics is greatly improved.

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An Analytical Tension Model for Continuum Robots with n Generally Positioned Tendons

Journal of Medical Robotics Research ◽

10.1142/s2424905x19420030 ◽

2019 ◽

Vol 04 (03n04) ◽

pp. 1942003

Author(s):

Mohsen Moradi Dalvand ◽

Saeid Nahavandi ◽

Robert D. Howe

Keyword(s):

Stereo Vision ◽

Control Algorithm ◽

Open Loop ◽

Open Loop Control ◽

Continuum Robots ◽

Loop Control ◽

Proposed Model ◽

Continuum Robot ◽

Tension Loading ◽

Tendon Compliance

The estimation of tension loads in multi-tendon continuum robots or catheters plays an important role not only in the design process but also in the control algorithm to avoid slack. An analytical tension loading model is developed that, for any given beam configuration within the workspace, calculates tendon tensions in [Formula: see text]-tendon continuum robots with general tendon positioning. The model accounts for the bending and axial compliance of the manipulator as well as tendon compliance. A 6-tendon continuum robot integrated with a stereo vision-based 3D reconstruction system is utilized to experimentally validate the proposed analytical model in open-loop control architecture. The proposed model demonstrates around 95% accuracy in estimating tendon tensions in a continuum robot with general tendon positioning and axial stretch in its tendons for all of the trials and experiments.

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PWM Control Accuracy for Scratch Drive Actuators

ASME 2010 Dynamic Systems and Control Conference, Volume 2 ◽

10.1115/dscc2010-4119 ◽

2010 ◽

Author(s):

Jenelle Armstrong Piepmeier ◽

Samara L. Firebaugh

Keyword(s):

Open Loop ◽

Open Loop Control ◽

Forward Motion ◽

Loop Control ◽

Wheeled Vehicle ◽

Straight Line ◽

Fixed Radius ◽

Turning Radius ◽

Wheeled Vehicles ◽

Control Accuracy

In this paper we investigate the problem of controlling a scratch drive actuator that has two discrete modes of locomotion: forward motion in a straight line, and forward motion with fixed radius curvature. This type of device can be modeled as a two-wheeled vehicle (with the previously stated constraints). By alternating between these two modes of operation, the device can move along a variable-radius curved path. In practice, the robots do not move in a purely straight manner. This paper seeks to quantify the accuracy that can be achieved by switching between the two modes of locomotion. This type of low-level open-loop control facilitates the use of a higher level feedback controller designed for two-wheeled vehicles with a variable turning radius.

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Interleaved DC-DC Converter with Discrete Duty Cycle and Open Loop Control

Latvian Journal of Physics and Technical Sciences ◽

10.1515/lpts-2016-0024 ◽

2016 ◽

Vol 53 (4) ◽

pp. 14-21

Author(s):

K. Kroics ◽

A. Sokolovs

Keyword(s):

Duty Cycle ◽

Control Algorithm ◽

Open Loop ◽

Current Loop ◽

Open Loop Control ◽

Output Current ◽

Loop Control ◽

Control Principle ◽

Conduction Mode ◽

Current Ripple

Abstract The authors present the control principle of the multiphase interleaved DC-DC converter that can be used to vastly reduce output current ripple of the converter. The control algorithm can be easily implemented by using microcontroller without current loop in each phase. The converter works in discontinuous conduction mode (DCM) but close to boundary conduction mode (BCM). The DC-DC converter with such a control algorithm is useful in applications that do not require precise current adjustment. The prototype of the converter has been built. The experimental results of the current ripple are presented in the paper.

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Backup Nutation Damping Strategy for the Galileo Spacecraft

Journal of Dynamic Systems Measurement and Control ◽

10.1115/1.2896380 ◽

1991 ◽

Vol 113 (2) ◽

pp. 308-312

Author(s):

F. O. Eke ◽

E. M. Eke

Keyword(s):

Motion Compensation ◽

Control Algorithm ◽

Open Loop ◽

Remedial Measures ◽

Open Loop Control ◽

Spacecraft Motion ◽

Loop Control ◽

Compensation Algorithm

This paper discusses the design of remedial measures that can be taken to achieve reasonable nutation damping of the Galileo spacecraft in the event of failure of its boom damper in flight. One scheme exploits the effects of payload motion on the nutational stability of a spinning spacecraft. This scheme demands that the spacecraft motion compensation algorithm be enabled with the scan platform bore sight pointed in a well chosen direction to produce rapid damping of spacecraft nutation. A second method suggested for nutation damping is a thruster-based open loop control algorithm, utilizing a pair of thrusters as actuators.

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Research on system modeling and motion control simulation of automatic power trowel

Journal of Physics Conference Series ◽

10.1088/1742-6596/2125/1/012031 ◽

2021 ◽

Vol 2125 (1) ◽

pp. 012031

Author(s):

Hao Xu ◽

Yutian Zhu ◽

Mo Chen ◽

Zhao Liu

Keyword(s):

Control Algorithm ◽

Control Method ◽

System Modeling ◽

Open Loop ◽

State Feedback Control ◽

Open Loop Control ◽

Loop Control ◽

Point Motion ◽

Point To Point ◽

The Relationship

Abstract Aiming at the problems that the existing control researches on the power trowel are limited to the analysis of the motion principle and the open-loop control of some mechanisms, taking a hydraulically-driven ride-on power trowel as the research object, the closed-loop control method of the point-to-point motion of the power trowel is studied. After analyzing the motion principle of the power trowel, based on the assumption of elastic deformation of concrete, the dynamic model of a single trowel is established, and the relationship between the driving force, driving moment and hydraulic moment, velocity, and angular velocity of the trowel is obtained. The whole machine motion equation of the power trowel is deduced, the point-to-point state feedback control algorithm of the power trowel is studied, and a simulation model is built to verify the accuracy of the system model of the power trowel and the effectiveness of the control algorithm. This research can provide reference for the control method design of other complex motions of the power trowel.

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Optimal Control of Nonlinear Structures

Journal of Applied Mechanics ◽

10.1115/1.3173744 ◽

1988 ◽

Vol 55 (4) ◽

pp. 931-938 ◽

Cited By ~ 47

Author(s):

J. N. Yang ◽

F. X. Long ◽

D. Wong

Keyword(s):

Optimal Control ◽

Control Systems ◽

Active Control ◽

Control Algorithm ◽

Open Loop ◽

Control Algorithms ◽

Nonlinear Structures ◽

Open Loop Control ◽

Loop Control ◽

Optimal Control Algorithms

Three optimal control algorithms are proposed for reducing oscillations of flexible nonlinear structures subjected to general stochastic dynamic loads, such as earthquakes, waves, winds, etc. The optimal control forces are determined analytically by minimizing a time-dependent quadratic performance index, and nonlinear equations of motion are solved using the Wilson-θ numerical procedures. The optimal control algorithms developed for applications to nonlinear structures are referred to as the instantaneous optimal control algorithms, including the instantaneous optimal open-loop control algorithm, instantaneous optimal closed-loop control algorithm, and instantaneous optimal closed-open-loop control algorithm. These optimal algorithms are computationally efficient and suitable for on-line implementation of active control systems to realistic nonlinear structures. Numerical examples are worked out to demonstrate the applications of these optimal control algorithms to nonlinear structures. In particular, control of structures undergoing inelastic deformations under strong earthquake excitations are illustrated. The advantage of using combined passive/active control systems is also demonstrated.

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