Tractor-trailer-train braking time sequence detection based on monocular vision

2021 ◽  
Vol 13 (12) ◽  
pp. 168781402110670
Author(s):  
Libin Zhang ◽  
Shiyuan Feng ◽  
Hongying Shan ◽  
Guanran Wang
Keyword(s):  
Template Matching ◽  
Slip Rate ◽  
Calibration Method ◽  
Time Sequence ◽  
Monocular Vision ◽  
Sequence Detection ◽  
Detection Scheme ◽  
Intelligent Detection ◽  
Vehicle Test ◽  
Braking Process

The tractor-trailer-train at the braking process prone to braking instability caused by asynchronous braking between the shafts. With respect to the lack of intelligent detection of Braking Time Sequence (BTS), a non-contact dynamic detection scheme of intelligent vehicle BTS is proposed. Based on the monocular vision principle, the edge markers of tractor-trailer train tires are identified, and the tire slip rate is solved. The noise reduction of the collected image is processed. The marker area is obtained by Blob analysis. This region at the image to be matched is identified by the template matching algorithm based on contour. The camera is calibrated by Zhang’s calibration method. In order to verify the effectiveness of the detection scheme, the real vehicle test was carried out. The test results show that the error of slip rate solution is below 4.2%.

Industrial part localization and grasping using a robotic arm guided by 2D monocular vision

2018 ◽  
Vol 45 (6) ◽  
pp. 794-804 ◽  
Author(s):  
Zhaohui Zheng ◽  
Yong Ma ◽  
Hong Zheng ◽  
Yu Gu ◽  
Mingyu Lin
Keyword(s):  
Camera Calibration ◽  
High Precision ◽  
Calibration Method ◽  
Monocular Vision ◽  
Robotic Arm ◽  
Robot Arm ◽  
Content Type ◽  
Calibration Algorithm ◽  
Target Locating ◽  
Practical Implications

Purpose The welding areas of the workpiece must be consistent with high precision to ensure the welding success during the welding of automobile parts. The purpose of this paper is to design an automatic high-precision locating and grasping system for robotic arm guided by 2D monocular vision to meet the requirements of automatic operation and high-precision welding. Design/methodology/approach A nonlinear multi-parallel surface calibration method based on adaptive k-segment master curve algorithm is proposed, which improves the efficiency of the traditional single camera calibration algorithm and accuracy of calibration. At the same time, the multi-dimension feature of target based on k-mean clustering constraint is proposed to improve the robustness and precision of registration. Findings A method of automatic locating and grasping based on 2D monocular vision is provided for robot arm, which includes camera calibration method and target locating method. Practical implications The system has been integrated into the welding robot of an automobile company in China. Originality/value A method of automatic locating and grasping based on 2D monocular vision is proposed, which makes the robot arm have automatic grasping function, and improves the efficiency and precision of automatic grasp of robot arm.

A Real-Time Sequence Detection Algorithm for Floating Point Unit Design

2014 ◽  
Vol 687-691 ◽  
pp. 3494-3497
Author(s):  
Wei Sun ◽  
Jun She An ◽  
Shuang Yang
Keyword(s):  
Fixed Point ◽  
Real Time ◽  
Detection Algorithm ◽  
Time Sequence ◽  
Floating Point ◽  
Design Data ◽  
Sequence Detection ◽  
Unit Design ◽  
Floating Point Unit ◽  
Short Time

Sequence detection is used in many algorithms and applications. Sequences are different depending on different demands. In the process of floating-point CORDIC coprocessor design,data are need to change from floating point format to fixed point format. This process is necessary to detect the number of consecutive zeros. We design the leading-zero-counting algorithm to achieve this function, and this conversion process is completed in a very fixed short time, to ensure the needs of the floating point CORDIC coprocessor.

scholarly journals A New Model of Stopping Sight Distance of Curve Braking Based on Vehicle Dynamics

2016 ◽  
Vol 2016 ◽  
pp. 1-8 ◽  
Author(s):  
Rong-xia Xia ◽  
De-hua Wu ◽  
Jie He ◽  
Ya Liu ◽  
Deng-feng Shi
Keyword(s):  
Calculation Model ◽  
Emergency Situations ◽  
Process Dynamics ◽  
Sight Distance ◽  
Straight Line ◽  
Braking Distance ◽  
Vehicle Test ◽  
Stopping Sight Distance ◽  
Braking Process ◽  
Experimental Values

Compared with straight-line braking, cornering brake has longer braking distance and poorer stability. Therefore, drivers are more prone to making mistakes. The braking process and the dynamics of vehicles in emergency situations on curves were analyzed. A biaxial four-wheel vehicle was simplified to a single model. Considering the braking process, dynamics, force distribution, and stability, a stopping sight distance of the curve braking calculation model was built. Then a driver-vehicle-road simulation platform was built using multibody dynamic software. The vehicle test of brake-in-turn was realized in this platform. The comparison of experimental and calculated values verified the reliability of the computational model. Eventually, the experimental values and calculated values were compared with the stopping sight distance recommended by the Highway Route Design Specification (JTGD20-2006); the current specification of stopping sight distance does not apply to cornering brake sight distance requirements. In this paper, the general values and limits of the curve stopping sight distance are presented.

scholarly journals Monocular Vision Ranging and Camera Focal Length Calibration

2021 ◽  
Vol 2021 ◽  
pp. 1-15
Author(s):  
Lixia Xue ◽  
Meian Li ◽  
Liang Fan ◽  
Aixia Sun ◽  
Tian Gao
Keyword(s):  
Camera Calibration ◽  
Polynomial Regression ◽  
Focal Length ◽  
Three Dimensional ◽  
Calibration Method ◽  
Monocular Vision ◽  
Field Of Vision ◽  
Average Accuracy ◽  
Ground Object ◽  
The Relationship

The camera calibration in monocular vision represents the relationship between the pixels’ units which is obtained from a camera and the object in the real world. As an essential procedure, camera calibration calculates the three-dimensional geometric information from the captured two-dimensional images. Therefore, a modified camera calibration method based on polynomial regression is proposed to simplify. In this method, a parameter vector is obtained by pixel coordinates of obstacles and corresponding distance values using polynomial regression. The set of parameter’s vectors can measure the distance between the camera and the ground object in the field of vision under the camera’s posture and position. The experimental results show that the lowest accuracy of this focal length calibration method for measurement is 97.09%, and the average accuracy was 99.02%.

A Method on Monocular Vision of Camera for Spatial Position

2013 ◽  
Vol 281 ◽  
pp. 14-18 ◽  
Author(s):  
Zhen Yang ◽  
Ming Jun Wu ◽  
Fang Wang ◽  
Li Zhang ◽  
Li Na Gong
Keyword(s):  
Edge Detection ◽  
Geometric Model ◽  
Digital Camera ◽  
Calibration Method ◽  
Spatial Position ◽  
Monocular Vision ◽  
Feature Points ◽  
Intrinsic Parameter ◽  
Extrinsic Parameter ◽  
Parameter Matrix

In this paper, a method on monocular vision for spatial position is presented. The geometric model of digital camera is built and decomposed to intrinsic and extrinsic parameter matrixes under a certain assumption. Firstly, the intrinsic parameter matrix of camera is determined. Then, the extrinsic parameter matrix is solved according to the information of image. The edge detection operators are worked and in order to detect the accuracy of this method, the point of some feature points are obtained by using the principle of least squares. Compared with the conventional calibration method, this method is simple, fast and robust.

scholarly journals Research on the Coordinated Control of Regenerative Braking System and ABS in Hybrid Electric Vehicle Based on Composite Structure Motor

Electronics ◽  
2021 ◽  
Vol 10 (3) ◽  
pp. 223
Author(s):  
Qiwei Xu ◽  
Chuan Zhou ◽  
Hong Huang ◽  
Xuefeng Zhang
Keyword(s):  
Composite Structure ◽  
Energy Recovery ◽  
Slip Rate ◽  
Coordinated Control ◽  
Operating Efficiency ◽  
Regenerative Braking ◽  
Braking System ◽  
Antilock Braking System ◽  
Braking Process ◽  
Braking Energy Recovery

An antilock braking system (ABS) can ensure that the wheels are not locked during the braking process which is an important system to ensure the safety of braking. Regenerative braking is also a crucial system for hybrid vehicles and helps to improve the cruising range of the car. As such, the coordinated control of a braking system and an ABS is an important research direction. This paper researches the coordinated control of the regenerative braking system and the ABS in the hybrid vehicle based on the composite structure motor (CSM-HEV). Firstly, two new braking modes which are engine-motor coordinated braking (EMCB) and dual-motor braking (DMB) are proposed and the coordinated control model of regenerative braking and ABS is established. Then, for the purpose of optimal operating efficiency and guaranteeing the vehicle brake slip rate, a braking force distribution strategy based on predictive control algorithm is proposed. Finally, the Simulink model is established to simulate the control strategy. Results show that the slip rate can well track the target and ensure the efficient operation of the system. Compared with the normal braking mode, the braking energy recovery rate of EMCB is similar, but it can reduce the fuel loss of the engine during the braking process by 30.1%, DMB can improve the braking energy recovery efficiency by 16.78%, and the response time to track target slip is increased by 12 ms.

scholarly journals Research on Cooperative Braking Control Algorithm Based on Nonlinear Model Prediction

2021 ◽  
Vol 12 (4) ◽  
pp. 173
Author(s):  
Liang Chu ◽  
Cheng Chang ◽  
Di Zhao ◽  
Yanwu Xu
Keyword(s):  
Nonlinear Model ◽  
Energy Recovery ◽  
Control Algorithm ◽  
Slip Rate ◽  
Test Cycle ◽  
Braking System ◽  
System A ◽  
Braking Control ◽  
Vehicle Test ◽  
Braking Energy Recovery

To address the coordinated distribution of motor braking and friction braking for the regenerative braking system, a cooperative braking algorithm based on nonlinear model predictive control (NMPC) is proposed, with braking energy recovery power, tire slip rate, and motor torque variation as the optimization objectives, and online optimization of the coordinated distribution of motor braking and friction braking. Using the offline model built in Matlab/Simulink, the cooperative braking algorithm is tested for energy efficiency and braking safety. The results show that when based on World Light Vehicle Test Cycle (WLTC), the energy recovery rate can reach 30.4%, and with a single high braking intensity, the braking safety can still be ensured.

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