Vehicle Cruise Braking Distance Calibration based on Embedded CNC System

2021 ◽  
Vol 13 (4) ◽  
Author(s):  
Linsheng Wang ◽  
Donghe Xi
Keyword(s):  
Rolling Resistance ◽  
Calculation Model ◽  
Calibration Error ◽  
System Control ◽  
Vehicle Speed ◽  
Cnc System ◽  
Time Model ◽  
Air Resistance ◽  
Braking Distance ◽  
Embedded Cnc

Most of the vehicle cruise braking calibration algorithms only calibrate the distance, ignoring that the driver cannot control the vehicle braking in time under fatigue conditions. Therefore, an embedded CNC system is added to the vehicle cruise braking distance calibration algorithm to control the vehicle speed and prevent the vehicle from rear-end collisions. At this time, the CNC system uses incremental control to control the vehicle cruise braking. The reaction time model and braking distance calculation model under control increment are established. At the same time, air resistance and rolling resistance of cruise braking distance parameters are calculated. Cruise braking distance calibration is completed by integrating the two models, CNC system control increment, air resistance and rolling resistance parameters. The experimental analysis shows that the calibration error of the algorithm is within ±30cm and the calibration accuracy is high, which meets the practical application standard of cruise braking.

Ground Transportation: Road and Rail

2017 ◽  
Author(s):  
Peter Rez
Keyword(s):  
Internal Combustion Engines ◽  
Energy Use ◽  
Rolling Resistance ◽  
Electrical Energy ◽  
Combustion Engines ◽  
Peak Efficiency ◽  
Railroad Tracks ◽  
Air Resistance ◽  
Thin Structure ◽  
Main Disadvantage

Everything that rolls along the ground uses energy to overcome both rolling resistance and air resistance. Air resistance is more significant at higher speeds. Repeated accelerations dominate energy use in stop–start city driving. Not surprisingly, heavy, large SUVs use more energy to go a given distance than lighter, more streamlined cars. Due to the mismatch between the torque required and the rotation rate of the drive wheels, internal combustion engines in cars or trucks do not operate at their peak efficiency. Trains are the most efficient form of ground transportation due to both the lower rolling resistance of steel wheels on railroad tracks and the lower air resistance of its long and thin structure. A further advantage is that rail with fixed tracks can take advantage of the efficient generation of electrical energy. This is also obviously the main disadvantage; trains can only go where tracks have been laid.

Rollover Warning of Articulated Vehicles Based on a Time-To-Rollover Metric

1999 ◽  
Author(s):  
Bo-Chiuan Chen ◽  
Huei Peng
Keyword(s):  
Real Time ◽  
The Other ◽  
Roll Angle ◽  
Vehicle Speed ◽  
Time Model ◽  
Whole Process ◽  
Articulated Vehicles ◽  
Articulated Vehicle ◽  
The One ◽  
Accuracy Problem

Abstract A Time-To-Rollover (TTR) metric is proposed as the basis to assess rollover threat for an articulated vehicle. Ideally, a TTR metric will accurately “count-down” toward rollover regardless of vehicle speed and steering patterns, so that the level of rollover threat is accurately indicated. To implement TTR in real-time, there are two conflicting requirements. On the one hand, a faster-than-real-time model is needed. On the other hand, the TTR predicted by this model needs to be accurate enough under all driving scenarios. An innovative approach is proposed in this paper to solve this dilemma and the whole process is illustrated in a design example. First, a simple yet reasonably accurate yaw/roll model is identified. A Neural Network (NN) is then developed to mitigate the accuracy problem of this simplified real-time model. The NN takes the TTR generated by the simplified model, vehicle roll angle and change of roll angle to generate an enhanced NN-TTR index. The NN was trained and verified under a variety of driving patterns. It was found that an accurate TTR is achievable across all the driving scenarios we tested.

scholarly journals Bioenergetics and Biomechanics of Handcycling at Submaximal Speeds in Athletes with a Spinal Cord Injury

Sports ◽  
2020 ◽  
Vol 8 (2) ◽  
pp. 16 ◽  
Author(s):  
Gabriela Fischer ◽  
Pedro Figueiredo ◽  
Luca Paolo Ardigò
Keyword(s):  
Spinal Cord ◽  
Spinal Cord Injury ◽  
Rolling Resistance ◽  
Metabolic Cost ◽  
Mechanical Efficiency ◽  
Metabolic Power ◽  
Ecological Conditions ◽  
Air Resistance ◽  
Cord Injury ◽  
Biomechanical Parameters

Background: This study aimed at comparing bioenergetics and biomechanical parameters between athletes with tetraplegia and paraplegia riding race handbikes at submaximal speeds in ecological conditions. Methods: Five athletes with tetraplegia (C6-T1, 43 ± 6 yrs, 63 ± 14 kg) and 12 athletes with paraplegia (T4-S5, 44 ± 7 yrs, 72 ± 12 kg) rode their handbikes at submaximal speeds under metabolic measurements. A deceleration method (coasting down) was applied to calculate the rolling resistance and frontal picture of each participant was taken to calculate air resistance. The net overall Mechanical Efficiency (Eff) was calculated by dividing external mechanical work to the corresponding Metabolic Power. Results: Athletes with tetraplegia reached a lower aerobic speed (4.7 ± 0.6 m s−1 vs. 7.1 ± 0.9 m s−1, P = 0.001) and Mechanical Power (54 ± 15 W vs. 111 ± 25 W, P = 0.001) compared with athletes with paraplegia. The metabolic cost was around 1 J kg−1 m−1 for both groups. The Eff values (17 ± 2% vs. 19 ± 3%, P = 0.262) suggested that the handbike is an efficient assisted locomotion device. Conclusion: Handbikers with tetraplegia showed lower aerobic performances but a similar metabolic cost compared with handbikers with paraplegia at submaximal speeds in ecological conditions.

Research of RTCP Function for Five-Axis Machine Tools Based on Low-Cost Embedded CNC System

2016 ◽  
Vol 693 ◽  
pp. 1591-1597
Author(s):  
Xiang Xiang Zou ◽  
Yan Yu Ding ◽  
Tai Yong Wang ◽  
Zhen Sang ◽  
He Nan Xu
Keyword(s):  
Machine Tools ◽  
Low Cost ◽  
High Grade ◽  
Arc Length ◽  
Cnc System ◽  
Offset Distance ◽  
Rtcp Function ◽  
Computational Resources ◽  
Five Axis ◽  
Embedded Cnc

To solve the problem which current research of RTCP function is limited to high-grade CNC system. Based on limited computational resources of the embedded CNC system, analyzes and modeling calculates RTCP function of CA double swing structure, and points out the offset distance is only related to the chord length corresponding to the arc length that the rotating radius crosses, and obtains the calculation formula of compensation. Finally, gives the implementing flow chart of the RTCP algorithm for low-cost embedded CNC system.

Research and Design of Embedded CNC System Based on CAN Bus Technology

2014 ◽  
Vol 494-495 ◽  
pp. 1373-1376
Author(s):  
Yan Hui Cheng
Keyword(s):  
High Performance ◽  
Local Area Network ◽  
Can Bus ◽  
Local Area ◽  
Area Network ◽  
Price Ratio ◽  
Cnc System ◽  
Nc System ◽  
Set Up ◽  
Embedded Cnc

This paper is based on the expansion of the CAN bus interface on ARM so that the embedded CNC system to achieve network, and display their respective advantages of field bus technology and embedded technology, so that to set up local area network embedded NC system model. The CNC system designed in this paper has characteristic as follows: high integration, flexible structure, good expansibility and the high performance-to-price ratio and so on.

Research of Precision CNC Internal Grinder Soft-PLC System Based on Embedded Technology

2012 ◽  
Vol 430-432 ◽  
pp. 1925-1928
Author(s):  
Ou Xie ◽  
Hua Li ◽  
Zhen Yin
Keyword(s):  
Software Design ◽  
System Integration ◽  
Cnc System ◽  
Open Cnc ◽  
Logic Control ◽  
Soft Plc ◽  
Design Idea ◽  
Open Cnc System ◽  
And Control ◽  
Embedded Cnc

According to the processing and control requirements of precision CNC internal grinder, a design of ARM-based embedded precision CNC internal grinder soft-PLC system was proposed. The design idea of open CNC system was introduced and the system hardware and software were packaged as the components to develop the PLC applications, achieved the logic control of the machine tool. This design meets the requirements of software design instead of hardware design and system integration development of embedded CNC system, achieved the real-time process control and improved the precision.

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.

Application of MECHATROLINK-II Fieldbus in Multi-Axis Embedded CNC System

2011 ◽  
Vol 314-316 ◽  
pp. 1695-1701
Author(s):  
Wei Qiang Gao ◽  
Chao Ting Qing ◽  
Ze Hua Hu ◽  
Zou Ya Huang
Keyword(s):  
Embedded Systems ◽  
Embedded System ◽  
Real Time ◽  
Numerical Control ◽  
Control Problems ◽  
Cnc System ◽  
Control Field ◽  
Synchronous Control ◽  
Embedded Cnc ◽  
Transmission Bottleneck

Recently, the application of fieldbus is becoming a trend in the development of CNC system towards decentralisation, network and multi-axis linkage. It is anticipated that fieldbus will be one of the leading technologies in the area of numerical control before long. Meanwhile, embedded system has been widely used in numerical control field to solve the reliability and real-time problems. In order to give full play to the advantages of embedded systems, the MECHATROLINK-II fieldbus is introduced to solve the transmission bottleneck of servo communications and multi-axis synchronous control problems. And it is proved that the application scheme combined fieldbus and embedded system is successful and valid by a large amount of performance testings.

scholarly journals DIMENSIONAREA SISTEMULUI DE PROPULSIE AL UNUI VEHICUL ELECTRIC. STUDIU DE CAZ

2021 ◽  
Vol 2020 (1) ◽  
pp. 1-14
Author(s):  
Alexandru TURCANU ◽  
Leonard-Călin-Valentin DOBRE
Keyword(s):  
Traction Force ◽  
Rolling Resistance ◽  
Resistance Coefficient ◽  
Gear Ratio ◽  
Calculation Model ◽  
The Road ◽  
Electric Car ◽  
Resistive Forces ◽  
Wheel Radius ◽  
Resistance Forces

This paper aims to present to readers concrete mathematical models, transposed into simulation schemes, to calculate the forces acting on a car at its interaction with the road and the atmosphere, to properly size the electric motor and batteries of an electric car. For the calculation of these forces, a table with predefined values ​​such as vehicle mass, rolling resistance coefficient, gear ratio, wheel radius, was used throughout the work. In the second section of the paper, the values ​​of the resistance forces that oppose the movement of the vehicle and the traction force necessary to overcome these resistive forces were determined. The mathematical calculation model was compiled in Matlab and the graphs in figures 3-9 were obtained.

Variable Control Setting to Enhance Rail Vehicle Braking Safety

2020 ◽  
Author(s):  
Sundar Shrestha ◽  
Maksym Spiryagin ◽  
Qing Wu
Keyword(s):  
Control Algorithm ◽  
Adhesion Force ◽  
Environmental Parameters ◽  
Vehicle Speed ◽  
Rail Vehicle ◽  
Potential Capacity ◽  
Braking Distance ◽  
Proper Definition ◽  
Definition Of ◽  
Adhesion Condition

Abstract Train braking technology needs to be advanced corresponding to the vehicle advancement to fully utilize the benefits of the potential capacity, efficiency and to ensure safety. The effectiveness of the braking changes as the friction condition at the wheel-rail interface and speed of rail vehicle change. The conventional brake control systems do not differentiate these changes in conditions and consider a constant slip reference. To overcome this issue, a new control algorithm for a wheel slide protection device incorporated in the electronically controlled pneumatic brake system has been proposed. Unlike conventional controllers, the proposed controller is responsive to the change of operational and environmental parameters between wheel and rail. It is designed based on multiple modes shifting during operations as the friction conditions change which allows to utilize the maximum adhesion available and to prevent the occurrence of sliding. The control algorithm is developed in a modular approach, where the first module identifies the adhesion condition at the wheel-rail interface. The result from the first module is further implemented in the second module to search for the optimum slip range for that adhesion condition and vehicle speed. For numerical simulation, a wagon model considering in-train forces is developed. The adhesion force is modeled by a proper definition of an adhesion-creep characteristics curve achieved from measured data. The comparison between the proposed control algorithm and the conventional algorithm suggests that the proposed control algorithm can optimally utilize available adhesion between wheel and rail to ensure shorter braking distance while maintaining vehicle stability.

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