Head-Raising Method of Snake Robots Based on the Bézier Curve

SUMMARY For acquiring a broad view in an unknown environment, we proposed a control strategy based on the Bézier curve for the snake robot raising its head. Then, an improved discretization method was developed to accommodate the backbone curves with more complex shapes. Besides, in order to determine the condition of using the improved discretization method, energy of framed space curve is introduced originally to estimate the shape complexity of the backbone curve. At last, based on degree elevation of the Bézier curve, an obstacle avoidance strategy of the head-raising motion was proposed and validated through simulation.

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A Head Control Strategy of the Snake Robot Based on Segmented Kinematics

Applied Sciences ◽

10.3390/app9235104 ◽

2019 ◽

Vol 9 (23) ◽

pp. 5104

Author(s):

Yunhu Zhou ◽

Yuanfei Zhang ◽

Fenglei Ni ◽

Hong Liu

Keyword(s):

Control Strategy ◽

Control Strategies ◽

The Body ◽

Head Part ◽

Joint Angles ◽

Backbone Curve ◽

Snake Robot ◽

Head Control ◽

Neck Part ◽

Snake Robots

Head control is important for snake robots to work in an unknown environment. However, the existing methods of head control have certain application limitations for snake robots with different configurations. Thus, a strategy for head control based on segmented kinematics is proposed. Compared with the existing head control strategies, our strategy can adapt to different structures of snake robots, whether wheeled or non-wheeled. In addition, our strategy can realize the accurate manipulation of the snake robot head. The robot body is divided into the base part, neck part and head part. First, parameters of backbone curve are optimized for enlarging the area of the support polygon. Then the desired pose for the head link and the dexterous workspace of the head part can in turn derive the desired position and direction of the end frame for the neck part. An optimization algorithm is proposed to help the end frame of the neck part approach a desired one and obtains the joint angles of the neck part. When the actual frames of the neck part are determined, the dexterous workspace of the head part will cover the desired pose of the head link. Then the TRAC-IK inverse kinematics algorithm is adopted to solve the joint angles of the head part. To avoid the collision between the body and the ground, a trajectory planning method of the overall body in Cartesian space is proposed. Finally, simulations validate the effectiveness of the control strategy.

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Degree elevation from Bézier curve to C-Bézier curve with corner cutting form

Applied Mathematics-A Journal of Chinese Universities ◽

10.1007/s11766-016-3369-0 ◽

2016 ◽

Vol 31 (2) ◽

pp. 165-176 ◽

Cited By ~ 1

Author(s):

Wan-qiang Shen ◽

Guo-zhao Wang

Keyword(s):

Bézier Curve ◽

Bezier Curve ◽

Degree Elevation ◽

Corner Cutting

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A NURBS transition between a Bézier curve and its control polygon

Journal of Computational and Applied Mathematics ◽

10.1016/j.cam.2021.113626 ◽

2021 ◽

pp. 113626

Author(s):

Imre Juhász

Keyword(s):

Bézier Curve ◽

Bezier Curve ◽

Control Polygon

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Optimal Bezier Curve Modification Function for Contrast Degraded Images

IEEE Transactions on Instrumentation and Measurement ◽

10.1109/tim.2021.3073320 ◽

2021 ◽

Vol 70 ◽

pp. 1-10

Author(s):

Bharath Subramani ◽

Ashish Kumar Bhandari ◽

Magudeeswaran Veluchamy

Keyword(s):

Bézier Curve ◽

Bezier Curve ◽

Degraded Images

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Automatic Lane-Changing Decision Based on Single-Step Dynamic Game with Incomplete Information and Collision-Free Path Planning

Actuators ◽

10.3390/act10080173 ◽

2021 ◽

Vol 10 (8) ◽

pp. 173

Author(s):

Hongbo Wang ◽

Shihan Xu ◽

Longze Deng

Keyword(s):

Path Planning ◽

Dynamic Game ◽

Single Step ◽

Bézier Curve ◽

Vehicle Safety ◽

Bezier Curve ◽

Lane Change ◽

Hardware In The Loop ◽

Power Performance ◽

Lane Changing

Traffic accidents are often caused by improper lane changes. Although the safety of lane-changing has attracted extensive attention in the vehicle and traffic fields, there are few studies considering the lateral comfort of vehicle users in lane-changing decision-making. Lane-changing decision-making by single-step dynamic game with incomplete information and path planning based on Bézier curve are proposed in this paper to coordinate vehicle lane-changing performance from safety payoff, velocity payoff, and comfort payoff. First, the lane-changing safety distance which is improved by collecting lane-changing data through simulated driving, and lane-changing time obtained by Bézier curve path planning are introduced into the game payoff, so that the selection of the lane-changing start time considers the vehicle safety, power performance and passenger comfort of the lane-changing process. Second, the lane-changing path without collision to the forward vehicle is obtained through the constrained Bézier curve, and the Bézier curve is further constrained to obtain a smoother lane-changing path. The path tracking sliding mode controller of front wheel angle compensation by radical basis function neural network is designed. Finally, the model in the loop simulation and the hardware in the loop experiment are carried out to verify the advantages of the proposed method. The results of three lane-changing conditions designed in the hardware in the loop experiment show that the vehicle safety, power performance, and passenger comfort of the vehicle controlled by the proposed method are better than that of human drivers in discretionary lane change and mandatory lane change scenarios.

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