Feedback Control of Non-holonomic Mobile Robots by Path-generating Regulator

Mathematical Problems in Engineering

Kazama

et al. 2014

Self Cite

The improved path-generating regulator (PGR) is proposed to path track the circle/arc passage for two-wheeled robots. The PGR, which is a control method for robots so as to orient its heading toward the tangential direction of one of the curves belonging to the family of path functions, is applied to navigation problem originally. Driving environments for robots are usually roads, streets, paths, passages, and ridges. These tracks can be seen as they consist of straight lines and arcs. In the case of small interval, arc can be regarded as straight line approximately; therefore we extended the PGR to drive the robot move along circle/arc passage based on the theory that PGR to track the straight passage. In addition, the adjustable look-ahead method is proposed to improve the robot trajectory convergence property to the target circle/arc. The effectiveness is proved through MATLAB simulations on both the comparisons with the PGR and the improved PGR with adjustable look-ahead method. The results of numerical simulations show that the adjustable look-ahead method has better convergence property and stronger capacity of resisting disturbance.

Section: The Influence Of Coefficient Constantmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

An Improved Path-Generating Regulator for Two-Wheeled Robots to Track the Circle/Arc Passage

Dai

Mathematical Problems in Engineering

Kazama

et al. 2014

Self Cite

“…Assuming that the steering angular velocityφ = u 2 , we can obtain the following mathematical model of two-wheeled mobile robot [11].ẋ…”

Section: Mathematical Model Of Two-wheeled Mobile Robotmentioning

confidence: 99%

“…Path-generating regulator(PGR) is a method aimed at controlling mobile robot to move in the tangential direction of the path which passes through the current position of the robot among the path group [11]. The purpose is to make the robot stop at the origin of the rectangular coordinate system fixed to the ground.…”

Section: Introductionmentioning

confidence: 99%

Path-generating regulator along a straight passage for two-wheeled mobile robots

Yang

2013 IEEE/RSJ International Conference on Intelligent Robots and Systems

Yamamoto

et al. 2013

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In this paper, the path-generating regulator is extended to tracking problem along a straight passage for two-wheeled mobile robots. As most of mobile robots are with nonholonomic constraints, it is difficult for us to make them converge to the target state with a control law. To solve this problem, many methods have been proposed. One of them is Path-generating Regulator(PGR) which designs a nonlinear regulator carrying out asymptotic convergence to a given trajectory family. However, the original method is not well suited for passages. In this paper, we will present the extended PGR for the tracking problem along a straight passage. Numerical simulations and experiments are also performed to show the effectiveness of this method.

“…As described in this paper, the Path-generating Regulator (PGR) algorithm is applied to robot control (Takashima, et al, 2004). Unlike other methods, the PGR is neither the coordinate transformation nor the input transformation.…”

Section: Introductionmentioning

confidence: 99%

Steering angle saturation analysis in PGR under feedback gain switching strategy for car-like robots

Dai

Mechanical Engineering Journal

Kazama

et al. 2014

Self Cite

This work analyzes the influence of steering angle saturation to the convergent property in the Path-generating Regulator (PGR) under the feedback gain switching strategy for car-like robots. The PGR control method carries out asymptotic convergence to a given path function group. It has been extended to car-like robots, and its convergent region has been expanded by the feedback gain switching strategy. However, under this strategy, when the robot restarts after the feedback gain switches, the command of the steering angle tends to be close to ±π/2 rad, which might exceed the maximum steering angle. This phenomenon causes steering angle saturation. The robot then drives along the minimum turning circle. In this paper, the convergent property of the robot under steering angle saturation is investigated first. Results show that the convergent property is related strongly to the number of singular points, which depends on the center location of the minimum turning circle. Then the convergent properties at different locations are clarified through region division. Moreover, an extended feedback gain switching strategy method is proposed to change the convergent property in the specific region. Based on simulation and experiment results, we summarize the convergent property related to the region and verify the proposed method.