scholarly journals STUDY OF FOUR-WHEEL STEERING SYSTEMS’ VIABILITY IN FUTURE AUTOMOBILES

2021 ◽  
Vol 6 (2) ◽  
Author(s):  
Aayush Soni ◽  
Adarsh Sahu ◽  
Prakhar Shrivastava ◽  
Shubhrata Nagpal
Keyword(s):  
High Speed ◽  
Rear Wheel ◽  
Steering System ◽  
Front Wheel ◽  
Low Speed ◽  
Medium Speed ◽  
Turning Radius

- Presently, all vehicles have a two-wheel steering system irrespective of the vehicle being front wheel driven, rear wheel driven or all-wheel driven. A four-wheel steering system known as “quadra steering” system is a system in which both the front wheels and rear wheels get steered according to the speed of the vehicle and space available for turning. This system makes the vehicle more stable and enhances its performance. In this report, the performance of quadra steering system has been considered under low speed, medium speed and high-speed conditions. For parking and low speed conditions, rear wheels are turned in the opposite directions while at medium and high-speed conditions, rear wheels and front wheels are turned in the same direction. As a result, the vehicle becomes more stable and its turning radius reduces greatly.

Modeling and Analysis of the Proportional Control Four-Wheel Steering Vehicle Handling and Stability

2013 ◽  
Vol 376 ◽  
pp. 243-247 ◽  
Author(s):  
Shi Jun Zhang ◽  
Hui Zhi Sun
Keyword(s):  
Dynamic Equation ◽  
High Speed ◽  
Lateral Force ◽  
Rear Wheel ◽  
Vehicle Dynamic ◽  
Vehicle Handling ◽  
Modeling And Analysis ◽  
Turning Radius ◽  
Vehicle Dynamic Model ◽  
Two Degree Of Freedom

Four-wheel steering (4ws) refers to the meaning of besides usually turn the front wheels of the vehicle, plus the corresponding rear wheel steering. Its main purpose is to increase the vehicle steering stability at high speed or in lateral force under the action , improve the vehicle steering portability at low speed and turning radius at high speed.A 4ws vehicle dynamic model with two-degree of freedom[1,2] was established, and presents the corresponding dynamic equation. Using the theory of vehicle handling dynamics,according to the 4ws vehicle dynamic equation,the transient response of 4ws vehicle steering are detailed analyzed.Compared with 2ws steering, illustrates the manipulation of 4ws vehicle has strong handling stability.

Implementation of SSM to Lateral Guided Steering Vehicle With Body Fixed High-Speed Camera

2013 ◽  
Author(s):  
Yoshihiro Takita ◽  
Date Hisashi
Keyword(s):  
High Speed ◽  
Rear Wheel ◽  
Front Wheel ◽  
Dump Truck ◽  
Reverse Phase ◽  
Automated Vehicle ◽  
Steering Mechanism ◽  
And Performance ◽  
The Stability ◽  
Rotating Camera

This paper proposes an SSM (Sensor Steering Mechanism) for a lateral guided vehicle with an articulated body. Authors demonstrated a simple lateral guiding method SSM for front wheel steer type, the reverse phase four-wheel steer type and rear wheel steer type vehicles. SSM presents a stable lateral guiding performance for automated vehicle that following a straight and curved path created by a guideway. This paper proposes a simplified SSM to remove the following servo system for a rotating camera. The simplified SSM is applied to 1/25 scale articulated dump truck that was developed and discussed in the previous paper. The stability of the simplified SSM is discussed. Experimental and simulation results show stable movement and performance of the proposed method.

scholarly journals Optimization of Four Wheel Steering

2018 ◽  
Vol 6 (02) ◽  
Author(s):  
R. Vigneshwaran ◽  
K. Saalai Chaithanyan ◽  
N. Sathish ◽  
S. Prashanth ◽  
M. Parasaran
Keyword(s):  
Steering System ◽  
Front Wheel ◽  
Full Size ◽  
Low Speed ◽  
And Control

A Four wheel steering system also known as Quadra steering system. In this paper, both front wheel and rear wheels can be steered according to speed other vehicle and space available for turning. Quadra steer gives full size vehicle greater ease while driving at low speed, improves stability, handling and control at higher speed. Production-built cars tend to under steer or, in few instances, overseer. If a car could automatically compensate for an under steer overseer problem, the driver would enjoy nearly neutral steering under varying conditions.

Research on Elastic Damping Control Strategy at High Speed for a Vehicle Electronic Power Steering System Stability

2014 ◽  
Vol 620 ◽  
pp. 240-245
Author(s):  
Xin Lei Ma ◽  
Yong Feng Guo ◽  
Ping Shi ◽  
Yue Guo
Keyword(s):  
Control Strategy ◽  
High Speed ◽  
Steering System ◽  
Front Wheel ◽  
System Stability ◽  
Control Technique ◽  
System Control ◽  
Damping Force ◽  
Power Steering ◽  
Resistance Decrease

Electronic power steering (EPS) system is a critical component for vehicle safety driving. The damping force of automobile steering is decreased at high speeds, so the driving feel is floating. When vehicle suspension shock and a front wheel sensitive to road counterforce it is relation with the driver safety. For the subject of vehicle stability at high speed, an EPS system control strategy of stability has been presented. In order to keep driving feel, when the steering resistance decrease an elastic damping will be increased. Current follow control technique is introduced, and the torque sensor can estimate the vehicle state. This method can be verified by the experiment.

A Multibody Motorcycle Model for the Analysis and Prediction of Chatter Vibrations

2013 ◽  
Author(s):  
Giuseppe Catania ◽  
Luca Leonelli ◽  
Nicolò Mancinelli
Keyword(s):  
High Speed ◽  
Three Dimensional ◽  
Rear Wheel ◽  
Front Wheel ◽  
Critical Discussion ◽  
Chatter Vibrations ◽  
Race Track ◽  
Chain Transmission ◽  
Linearized System ◽  
Overall Performance

The chatter phenomenon, appearing during high speed cornering maneuvers performed by racing motorcycles, consists of a self-excited vertical oscillation of both the front and rear unsprung masses in the range of frequency between 17 and 22 Hz. The suspensions are not generally able to dampen the above vibrations which start from the rear wheel and suddenly propagate to the front wheel during the corner entry phase, making the vehicle’s handling unpredictable and, ultimately, weakening the overall performance, that is the lap time. It is not clear which is the determining factor causing this phenomenon. Therefore, numerical simulation on a three dimensional, multibody motorcycle model is proposed, taking into account the effects of the major parameters involved, in order to highlight which of them takes part in the vibration. Accurate models for tire and drivetrain have been developed, making it possible to consider tire carcass deformability, chain transmission in both traction and braking states, full drivetrain inertia and anti-hop clutch effect. A critical maneuver experimentally measured on the race track is analyzed. The modal response of the linearized system is evaluated for several configurations extracted from the maneuver. The above maneuver is then simulated with the model, showing the actual vibration uprising. A critical discussion of the possible physical interpretations of the phenomenon is given.

scholarly journals Effects of Airspeed on the Respiratory Rate, Rectal Temperature, and Immunity Parameters of Dairy Calves Housed Individually in an Axial-Fan-Ventilated Barn

Animals ◽  
2021 ◽  
Vol 11 (2) ◽  
pp. 354
Author(s):  
Wanying Zhao ◽  
Christopher Choi ◽  
Dapeng Li ◽  
Geqi Yan ◽  
Hao Li ◽  
...  
Keyword(s):  
High Speed ◽  
Negative Impact ◽  
Warm Season ◽  
Dairy Calves ◽  
Immune Functions ◽  
Axial Fan ◽  
Low Speed ◽  
Select Group ◽  
Speed Flow ◽  
Medium Speed

At many modern dairy farms, calves raised in barns are kept in individual stalls separated by solid partitions, which act as barriers. Ventilation fans blowing air perpendicular to these stalls only provide the optimal airflow to the first few calves, while those further away receive a slower airflow. To ascertain whatever effects different airflow speeds may have on the health of animals kept in stalls located at increasing distances from ventilation fans, we divided a select group of 43 Holstein dairy calves into six subgroups based on age, and each subgroup was subjected to either a specified high-speed or low-speed airflow as follows: (1) Six 3-day-olds received high-speed airflow (D3-HA); (2) Six 3-day-olds received low-speed airflow (D3-LA); (3) Eight 19 (±3)-day-olds received high-speed airflow (D19-HA); (4) Eight 19 (± 3)-day-olds received low-speed airflow (D19-LA); (5) Eight 29 (±3)-day-olds received high-speed airflow (D29-HA); and (6) Seven 29 (±3)-day-olds received medium-speed airflow (D29-MA). These trials show that the rectal temperatures and respiratory rates of D19-LA (39.37 °C; 72.90 breaths/min) were significantly higher than those of D19-HA (39.14 °C; 61.57 breaths/min) (p ≤ 0.05), and those of D29-MA (39.40 °C; 75.52 breaths/min) were significantly higher than those of D29-HA (39.20 °C; 68.41 breaths/min) (p ≤ 0.05). At 33 (±3) days of age, those calves receiving high-speed airflow (p ≤ 0.05) registered significantly higher immunoglobulins A and M than calves receiving low-speed flow. Those calves subjected to a high-speed airflow also registered significantly lower tumor necrosis factor levels than those receiving low-speed flow (p ≤ 0.05). Among the 29 to 43-day-old calves, no significant differences in immunity parameters were found to exist between groups D29-HA and D29-MA. On the basis of these findings, we were able to conclude that in the warm season, when the calves were less than 0.5 months old, low-speed (0.17–0.18 m/s) airflows had no significant effect on calves; when the calves were 1 month old, low-speed airflow (0.20–0.21 m/s) may impair the immune functions; when the calves were 1 to 1.5 months old, the airflow velocity higher than 0.9 m/s can meet the needs of the calf without a negative impact on the calf.

Research on the Steering Character for Kiloton all Terrain Crane

2014 ◽  
Vol 1078 ◽  
pp. 187-190
Author(s):  
Zhong Ying Liu
Keyword(s):  
Deflection Angle ◽  
Steering System ◽  
Front Wheel ◽  
All Wheel Steering ◽  
Turning Radius ◽  
Minimum Turning Radius ◽  
Vehicle Capacity ◽  
Relationship Of ◽  
The Relationship ◽  
Two Degree Of Freedom

Based on the two degree of freedom model of kiloton all-terrain crane, he effects of relationship of deflection angle on turning radius were investigated in multi-axle steering system. MATLAB/Simulink was used to analyze the relationship of every axle in multi-axle steering and optimize the minimum turning radius. The studies show that the kiloton all-terrain crane adapted all-wheel steering driving at 5speed , and the front wheel angle was 32.3°, as compared to the rolling radius before optimization, the turning radius in all wheel turnaround reduced by 33%, which improved the vehicle capacity through the complex curve and increased the vehicle steering flexibility.

Rear Wheel Steering Dynamics Compared to Front Steering

1990 ◽  
Vol 112 (1) ◽  
pp. 88-93 ◽  
Author(s):  
J. C. Whitehead
Keyword(s):  
High Speed ◽  
Rear Wheel ◽  
Front Wheel ◽  
Slip Angle ◽  
Vehicle Speed ◽  
Lateral Dynamics ◽  
High Speeds ◽  
Control Response ◽  
Steady State Responses ◽  
State Responses

The lateral dynamics of rear wheel steering vehicles are examined using low order linear mathematical models. The response to rear steer angle inputs differs significantly from the front wheel steering response at low speeds. However, both the transient and steady state responses become less dependent on which wheels are steered as vehicle speed increases. This fact indicates that the unusual fixed control response does not alone cause rear wheel steering vehicles to be unsafe at high speeds. The free control instability unique to rear wheel steering vehicles is analyzed using a torque input model which treats steer angle as a degree of freedom. The cause of this unstable weave mode and the stable front wheel steering weave mode is a ratio of tire slip angle to steer angle in excess of unity during high speed cornering.

scholarly journals Development of Program in VB to Compute Tractor Parameters on Automatic Steering

2017 ◽  
Vol 10 (3) ◽  
pp. 636-643
Author(s):  
Raghuvirsinh Parmar ◽  
Nitin Karwasra ◽  
Aseem Verma ◽  
Baldev Dogra
Keyword(s):  
Velocity Vector ◽  
Visual Basic ◽  
Rear Wheel ◽  
Steering System ◽  
Front Wheel ◽  
Trajectory Data ◽  
Turning Angle ◽  
Automatic Steering ◽  
Input Variables ◽  
Agricultural Tractor

A comprehensible Visual Basic (VB) computer program is developed to find out the tractor parameters for an automated steering system. Tractor parameters such as real wheel and front wheel trajectory coordinates, clockwise front and rear wheel angle and corrected front and rear wheel angle can be calculated. Front wheel trajectory data, rear wheel trajectory, distance between front and rear wheel(X13), Tractor velocity vector(V) and Tractor turning angle with center line are input variables for developed software. The tractor parameters are being calculated with the help of mathematical model which are already fed in program. The developed program successfully calculates the tractor parameters on automated steering . This developed software could guide an autonomous agricultural tractor in the field. Furthermore, software navigates agricultural tractor both in straight or curved path at normal field operational speed.

Study of Tool Materials Rapid Selection in Cutting 300M Steel

2012 ◽  
Vol 472-475 ◽  
pp. 986-990 ◽  
Author(s):  
Jun Xian Xie ◽  
Wu Yi Chen ◽  
Jian Fei Sun
Keyword(s):  
High Speed ◽  
Cutting Speed ◽  
Low Speed ◽  
Tool Materials ◽  
Speed Condition ◽  
300M Steel ◽  
Medium Speed ◽  
Tool Performance ◽  
The Relationship

The validity of tool materials rapid selection based on initial wear for milling 300M steel were investigated under different cutting speed condition. Wear experiments of three tool materials selected from 17 tools suggested by the tool makers were conducted at three levels of cutting speed: low speed (100.5m/min), medium speed (150.7 m/min) and high speed (201.0m/min).Wear curves of the three tool materials are obtained through the above wear experiments. The relationship between tool performance and initial wear is analysed based on the obtained wear curves.

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