Speed Guidance and Trajectory Optimization of Traffic Flow in a Low-Visibility Zone of a Highway Segment within Multiple Signalized Intersections

In a low-visibility environment, the speed of traffic flow is more discrete on highways, which easily causes traffic accidents. To improve the safety and efficiency level of low-visibility zones on highways, a comprehensive optimization control method is proposed. The method uses formations of a low-visibility zone to queue discrete vehicles from the upstream intersection. Then, according to the relationship between the arrival time of the fleet and the phase state of the intersection, speed guidance and trajectory optimization are carried out to improve the traffic efficiency of the fleet that enters the low-visibility zone. Finally, a low-visibility zone of a highway segment is analysed with different traffic flows for the main road and the secondary roads, and the results show that the proposed optimization control method can prevent trajectory overlap and effectively decrease traffic delays on highways.

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Analysis of the Relationship between the Number of Traffic Accidents and the Traffic Flow & Section Location in Extra Long Tunnel

Engineering ◽

10.4236/eng.2020.122007 ◽

2020 ◽

Vol 12 (02) ◽

pp. 71-81

Author(s):

Zhaoyou Ma ◽

Shouen Fang ◽

Shuo Liu ◽

Bowen Cai

Keyword(s):

Traffic Flow ◽

Traffic Accidents ◽

The Relationship

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Optimization Control of Cooperative Trajectory towards Dual Arms Based on Time-Varying Constrained Output State

Complexity ◽

10.1155/2021/5338134 ◽

2021 ◽

Vol 2021 ◽

pp. 1-18

Author(s):

Hui Zhang ◽

Wenbin Zha ◽

Xiangrong Xu ◽

Yongfei Zhu

Keyword(s):

Genetic Algorithm ◽

Trajectory Optimization ◽

Control Method ◽

Time Varying ◽

Pd Control ◽

Output State ◽

Optimization Control ◽

The Individual ◽

The Impact ◽

Dual Arm

Aiming at the impact and disturbance of dual-arm robots in the process of coordinated transportation, a dual-arm cooperative trajectory optimization control based on time-varying constrained output state is proposed. According to the constraint relationship of the end-effector trajectory of the dual-arm coordinated transportation, the joint space trajectory mathematical model of the dual-arm coordinated transportation was established by using the master-slave construction method. Based on the time impact optimization index of joint trajectory, a multiobjective nonlinear equation is established. Using random probability distribution to extract the interpolation features of nonuniform quintic B-spline trajectory, the feature optimization target is selected, and the Newton numerical algorithm is used for iterative optimization. At the same time, it is combined with an elite retention genetic algorithm to further optimize the target. Based on the disturbance and tracking problem, a PD control method based on time-varying constrained output state is proposed, and the control law is designed. Its convergence is verified by establishing the Lyapunov function equation and asymmetric term. The trajectory optimization results show that the proposed trajectory optimization method can increase the individual diversity and enhance the individual local optimization, thus avoiding the premature impact of the elite retention genetic algorithm. Finally, the proposed control method is simulated on the platform of Gazebo; compared with the traditional PD control method, the results show that the proposed control algorithm has high robustness, and the rationality of the coordinated trajectory control method is verified by the double-arm handling experiment.

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Robot trajectory optimization control of braiding for three-dimensional complex preforms

Journal of Engineered Fibers and Fabrics ◽

10.1177/15589250211043226 ◽

2021 ◽

Vol 16 ◽

pp. 155892502110432

Author(s):

Xinfu Chi ◽

Qiyang Li ◽

Hongxia Yan ◽

Sun Yize

Keyword(s):

Trajectory Optimization ◽

Control Method ◽

Three Dimensional ◽

Great Influence ◽

Variable Cross Section ◽

Variable Cross ◽

Robot Trajectory ◽

Optimization Control ◽

Braiding Angle

The quality of composite preform has great influence on its mechanical properties. Aiming at the problems of difficulty in robot teaching and unstable braiding angle in the process of braiding three-dimensional complex component, a control method of robot is proposed. Firstly, the mandrel is discretized to ensure that the axis of each discrete mandrel is perpendicular to the braiding point plane, and the orientation and direction of the tool center are calculated. Then, the take-up speed of the robot is calculated, so that the self-adjustment of the braiding angle can be realized in the braiding process. The experimental results show that the control method can effectively reduce the braiding angle error of variable cross-section mandrel within 2°, and can improve the quality of composite products in actual production.

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Single-Point Adaptive Control Method for Urban Mixed Traffic Flow

Journal of Advanced Transportation ◽

10.1155/2020/8827824 ◽

2020 ◽

Vol 2020 ◽

pp. 1-7

Author(s):

Xuelian Liu ◽

Huazhi Yuan ◽

Jie Hu ◽

Xinlong Jiao

Keyword(s):

Adaptive Control ◽

Traffic Flow ◽

Control Method ◽

Single Point ◽

Urban Traffic ◽

Motor Vehicles ◽

Control Effect ◽

Traffic System ◽

Traffic Efficiency ◽

Urban Mixed Traffic

In urban traffic, motor vehicles, nonmotor vehicles, pedestrians, and other traffic are mixed, which seriously affects the urban traffic efficiency. At the intersections of urban roads especially, the priority setting of various travel modes is crucial to improve the urban traffic efficiency. In the urban hybrid traffic system, the architecture and algorithm flowchart of the single-point adaptive control system for urban hybrid traffic flow are presented. The control effect of this method is verified by VISSIM software. The simulation results show that the traffic efficiency of the priority objects at the intersection is increased by 6.03%, and the overall traffic efficiency is also significantly improved. This method has a certain practical value.

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Using CrowdFlower to Study the Relationship between Self-Reported Violations and Traffic Accidents

SSRN Electronic Journal ◽

10.2139/ssrn.2535443 ◽

2014 ◽

Author(s):

Joost de Winter ◽

Miltos Kyriakidis ◽

Dimitra Dodou ◽

Riender Happee

Keyword(s):

Traffic Accidents ◽

The Relationship

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Coordinated optimization control of shield machine based on dynamic fuzzy neural network direct inverse control

Transactions of the Institute of Measurement and Control ◽

10.1177/0142331220980274 ◽

2020 ◽

pp. 014233122098027

Author(s):

Xuanyu Liu ◽

Wentao Wang ◽

Yudong Wang ◽

Cheng Shao ◽

Qiumei Cong

Keyword(s):

Fuzzy Neural Network ◽

Control Method ◽

Earth Pressure ◽

Screw Conveyor ◽

Inverse Control ◽

The Earth ◽

Coordinated Optimization ◽

Optimization Control ◽

Fuzzy Neural ◽

Shield Machine

During shield machine tunneling, the earth pressure in the sealed cabin must be kept balanced to ensure construction safety. As there is a strong nonlinear coupling relationship among the tunneling parameters, it is difficult to control the balance between the amount of soil entered and the amount discharged in the sealed cabin. So, the control effect of excavation face stability is poor. For this purpose, a coordinated optimization control method of shield machine based on dynamic fuzzy neural network (D-FNN) direct inverse control is proposed. The cutter head torque, advance speed, thrust, screw conveyor speed and earth pressure difference in the sealed cabin are selected as inputs, and the D-FNN control model of the control parameters is established, whose output are screw conveyor speed and advance speed at the next moment. The error reduction rate method is introduced to trim and identify the network structure to optimize the control model. On this basis, an optimal control system for earth pressure balance (EPB) of shield machine is established based on the direct inverse control method. The simulation results show that the method can optimize the control parameters coordinately according to the changes of the construction environment, effectively reduce the earth pressure fluctuations during shield tunneling, and can better control the stability of the excavation surface.

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