Research for the steering wheel shake during high-speed based transfer functions

2014 ◽  
Author(s):  
Z.H. Hu ◽  
D.L. Duan
Keyword(s):  
High Speed ◽  
Transfer Functions ◽  
Steering Wheel

scholarly journals The Changes of Ergonomic Engine Vibroacoustic Response Regarding Their Development

Energies ◽  
2021 ◽  
Vol 14 (14) ◽  
pp. 4215
Author(s):  
Radosław Wróbel ◽  
Lech Sitnik ◽  
Monika Andrych-Zalewska ◽  
Łukasz Łoza ◽  
Radostin Dimitrov ◽  
...  
Keyword(s):  
Human Health ◽  
Power Density ◽  
High Speed ◽  
Internal Combustion Engines ◽  
Spectral Power ◽  
Spectral Power Density ◽  
Steering Wheel ◽  
Combustion Engines ◽  
Head Restraint ◽  
Vibroacoustic Response

The article presents the results of research on the vibroacoustic response of internal combustion engines mounted in a vehicle. The vehicles studied belong to popular models, which became available in successive versions. Each group included vehicles of the same model of an older generation (equipped with a naturally aspirated engine) and of a newer generation, including downsized (and turbocharged) engines. Tests in each group were carried out under repeatable conditions on a chassis-load dynamometer. The vibrations were measured using single-axis accelerometers mounted on the steering wheel, engine, and driver’s head restraint mounting. The primary purpose of the study was to verify whether the new generations of vehicles equipped with additional high-speed elements (compressors) generate additional harmonics (especially those within the range potentially affecting travel comfort and human health) and whether there are significant changes in the distribution of spectral power density in the new generations. As the study showed, new generations of vehicles are characterized by a different vibroacoustic response, and the trend of change is the same in each of the families studied.

Airbag Inflators

1999 ◽  
Author(s):  
William G. Broadhead ◽  
D. Theodore Zinke
Keyword(s):  
High Speed ◽  
Motor Vehicle ◽  
Seat Belt ◽  
Design Parameters ◽  
Steering Wheel ◽  
Instrument Panel ◽  
Highway Traffic ◽  
National Highway Traffic Safety ◽  
Column Collapse ◽  
Wide Range

Abstract The design of an airbag restraint system presents a classic engineering challenge. There are numerous design parameters that need to be optimized to cover the wide range of occupant sizes, occupant positions and vehicle collision modes. Some of the major parameters that affect airbag performance include, the airbag inflator characteristics, airbag size and shape, airbag vent size, steering column collapse characteristics, airbag cover characteristics, airbag fold pattern, knee bolsters, seat, seat belt characteristics, and vehicle crush characteristics. Optimization of these parameters can involve extremely costly programs of sled tests and full scale vehicle crash tests. Federal Motor Vehicle Safety Standards (FMVSS) with regard to airbag design are not specific and allow flexibility in component characteristics. One design strategy, which is simplistic and inexpensive, is to utilize a very fast, high output gas generator (inflator). This ensures that the bag will begin restraining the occupant soon after deployment and can make up for deficiencies in other components such as inadequate steering column collapse or an unusually stiff vehicle crush characteristic. The use of such inflators generally works well for properly positioned occupants in moderate to high-speed frontal collisions by taking advantage of the principle of ridedown. When an airbag quickly fills the gap between the occupant and the instrument panel or steering wheel it links him to the vehicle such that he utilizes the vehicle’s front-end crush to help dissipate his energy, thus reducing the restraint forces. Unfortunately, powerful airbag systems can be injurious to anyone in the path of the deploying airbag. This hazard is present for short statured individuals, out of position children or any occupant in a collision that results in extra ordinary crash sensing time. Currently, the National Highway Traffic Safety Administration (NHTSA) is proposing to rewrite FMVSS 208 to help reduce such hazards.

Study on Driver and Vehicle System With Lane-Tracking Control System Using Steering Torque Input

2001 ◽  
Author(s):  
Masao Nagai ◽  
Hidehisa Yoshida ◽  
Kiyotaka Shitamitsu ◽  
Hiroshi Mouri
Keyword(s):  
Tracking Control ◽  
High Speed ◽  
Driving Simulator ◽  
Tracking System ◽  
Torque Control ◽  
Steering Wheel ◽  
Control Input ◽  
Steering Angle ◽  
Lane Tracking ◽  
Steering Torque

Abstract Although the vast majority of lane-tracking control methods rely on the steering wheel angle as the control input, a few studies have treated methods using the steering torque as the input. When operating vehicles especially at high speed, drivers typically do not grip the steering wheel tightly to prevent the angle of the steering wheel from veering off course. This study proposes a new steering assist system for a driver not with the steering angle but the steering torque as the input and clarifies the characteristics and relative advantages of the two approaches. Then using a newly developed driving simulator, characteristics of human drivers and the lane-tracking system based on the steering torque control are investigated.

An Evaluation of Stability Indices Using Sensitivity Functions for Active Magnetic Bearing Supported High-Speed Rotor

2006 ◽  
Vol 129 (2) ◽  
pp. 230-238 ◽  
Author(s):  
Naohiko Takahashi ◽  
Hiroyuki Fujiwara ◽  
Osami Matsushita ◽  
Makoto Ito ◽  
Yasuo Fukushima
Keyword(s):  
High Speed ◽  
Transfer Functions ◽  
Mimo System ◽  
Magnetic Bearing ◽  
Singular Value ◽  
Active Magnetic Bearing ◽  
Sensitivity Functions ◽  
Phase Lags ◽  
The Stability ◽  
Stability Indices

In active magnetic bearing (AMB) systems, stability is the most important factor for reliable operation. Rotor positions in radial direction are regulated by four-axis control in AMB, i.e., a radial system is to be treated as a multi-input multioutput (MIMO) system. One of the general indices representing the stability of a MIMO system is “maximum singular value” of a sensitivity function matrix, which needs full matrix elements for calculation. On the other hand, ISO 14839-3 employs “maximum gain” of the diagonal elements. In this concept, each control axis is considered as an independent single-input single-output (SISO) system and thus the stability indices can be determined with just four sensitivity functions. This paper discusses the stability indices using sensitivity functions as SISO systems with parallel/conical mode treatment and/or side-by-side treatment, and as a MIMO system with using maximum singular value; the paper also highlights the differences among these approaches. In addition, a conversion from usual x∕y axis form to forward/backward form is proposed, and the stability is evaluated in its converted form. For experimental demonstration, a test rig diverted from a high-speed compressor was used. The transfer functions were measured by exciting the control circuits with swept signals at rotor standstill and at its 30,000 revolutions/min rotational speed. For stability limit evaluation, the control loop gains were increased in one case, and in another case phase lags were inserted in the controller to lead the system close to unstable intentionally. In this experiment, the side-by-side assessment, which conforms to the ISO standard, indicates the least sensitive results, but the difference from the other assessments are not so great as to lead to inadequate evaluations. Converting the transfer functions to the forward/backward form decouples the mixed peaks due to gyroscopic effect in bode plot at rotation and gives much closer assessment to maximum singular value assessment. If large phase lags are inserted into the controller, the second bending mode is destabilized, but the sensitivity functions do not catch this instability. The ISO standard can be used practically in determining the stability of the AMB system, nevertheless it must be borne in mind that the sensitivity functions do not always highlight the instability in bending modes.

Needle Fatigue Analysis for High-Speed Knitting Machines

1995 ◽  
Author(s):  
Richard H. Lyon ◽  
Leonid M. Malinin
Keyword(s):  
High Speed ◽  
Transfer Functions ◽  
High Capacity ◽  
Time History ◽  
Stationary Problem ◽  
Element Analysis ◽  
Speed Increase ◽  
Design Engineers ◽  
Machine Element ◽  
Needle Longevity

Abstract In modern, high capacity circular knitting machines, the small and fragile latch needles are often a performance-limiting machine element (Schuler, 1980). For these machines, the operating circumferential speed may exceed 1.5 m/sec. Due to the kinematics of the process, the cam driven needles are exposed to periodic excitation with frequency proportional to the speed. Increase in rotational speed gives rise to needle head fatigue breakages unless special design measures are undertaken. Frequencies up to 15 kHz have been observed and up to 60 kHz may be expected in the vibration spectrum. To understand what particular features of needle design may be responsible for their longevity, several techniques were developed to apply Finite Element Analysis software to estimating the fatigue life under a non-harmonic periodic loading. The known FEA packages handle dynamics of a system with such loading as a general non-stationary problem, whereas much more efficient solution can be constructed by combining the analytical solution for a one DOF system under recurring impulses (5-functions of amplitude A) at the moments 0, T, 2T, …, and the natural modes of the system (with the driving point fixed) provided by FEA. As applied to the system in question, from the broad frequency range of the excitation forces and displacements, only frequencies close to those providing maxima to the transfer functions from the driving point to the head of the needle were selected. These frequencies are referred to further on as the response frequencies. Then the time history simulating polyharmonic stresses in the dangerous area was generated and processed according to the chosen fatigue criteria (a corrected linear hypothesis of damage summation, see below). Thus for any given node of the needle a point on the S-N diagram was obtained. A wide spread desktop package, ALGOR, was selected as a Linear Stress Analysis solver. The described procedure is built on top of this package and allows design engineers to make judgements as to what design is more advantageous for needle longevity.

Experimental Development of On-Line Flame Transfer Function Measurements for Fielded Gas Turbines

2021 ◽  
Author(s):  
Austin Matthews ◽  
Anna Cobb ◽  
Subodh Adhikari ◽  
David Wu ◽  
Tim Lieuwen ◽  
...  
Keyword(s):  
Transfer Function ◽  
Heat Release ◽  
Gas Turbine ◽  
Gas Turbines ◽  
High Speed ◽  
Transfer Functions ◽  
Full Scale ◽  
Fuel Injector ◽  
Experimental Development ◽  
On Line

Abstract Understanding thermoacoustic instabilities is essential for the reliable operation of gas turbine engines. To complicate this understanding, the extreme sensitivity of gas turbine combustors can lead to instability characteristics that differ across a fleet. The capability to monitor flame transfer functions in fielded engines would provide valuable data to improve this understanding and aid in gas turbine operability from R&D to field tuning. This paper presents a new experimental facility used to analyze performance of full-scale gas turbine fuel injector hardware at elevated pressure and temperature. It features a liquid cooled, fiber-coupled probe that provides direct optical access to the heat release zone for high-speed chemiluminescence measurements. The probe was designed with fielded applications in mind. In addition, the combustion chamber includes an acoustic sensor array and a large objective window for verification of the probe using high-speed chemiluminescence imaging. This work experimentally demonstrates the new setup under scaled engine conditions, with a focus on operational zones that yield interesting acoustic tones. Results include a demonstration of the probe, preliminary analysis of acoustic and high speed chemiluminescence data, and high speed chemiluminescence imaging. The novelty of this paper is the deployment of a new test platform that incorporates full-scale engine hardware and provides the ability to directly compare acoustic and heat release response in a high-temperature, high-pressure environment to determine the flame transfer functions. This work is a stepping-stone towards the development of an on-line flame transfer function measurement technique for production engines in the field.

Steering Analysis of Multi-Axle Vehicle Based on ADAMS/VIEW

2012 ◽  
Vol 538-541 ◽  
pp. 2878-2881
Author(s):  
Yong Qiang Zhu ◽  
Ping Xia Zhang
Keyword(s):  
High Speed ◽  
Large Angle ◽  
Lateral Acceleration ◽  
Steering Wheel ◽  
Low Speed ◽  
Vehicle Simulation ◽  
Yaw Rate ◽  
Wheel Turning ◽  
Double Phase ◽  
All Wheel Steering

In order to improve low-speed flexibility and high-speed handling and stability of multi-axle vehicle, a double-phase steering system was designed with planetary gear system. An in-phase steering mode is used when steering wheel turning in small angle. A adverse-phase steering mode is used when steering wheel turning in large angle. A five-axle vehicle simulation model was established with software ADAMS/VIEW. The research of all-wheel steering and non-all-wheel steering for high speed and low speed was respectively processed. When running in high speed, the lateral acceleration and yaw rate of the centroid are significantly lower when rear wheels steering in in-phase mode than the rear wheels not turning, which makes the possibility of roll and drift decrease, when vehicle overtaking in high-speed. When running in low speed, compared with rear wheels not steering, when rear wheels sreering, lateral acceleration increased by only 12.8%, yaw rate is 17.3% higher, diameter of the centroid trajectory is reduced by 12.9%, which greatly increases the mobility and flexibility of the multi-axle vehicle when turning at low speed.

Torque Neutrality for Active Steering Systems

2012 ◽  
Vol 134 (5) ◽  
Author(s):  
Jonas Müller
Keyword(s):  
Transfer Functions ◽  
Steering System ◽  
Experimental Results ◽  
System Model ◽  
Steering Wheel ◽  
Control Law ◽  
Feed Forward Control ◽  
Power Steering ◽  
Active Steering ◽  
Active Steering System

This paper outlines a method for using an active steering system with two electrical actuators (one power-steering actuator and one superposition actuator) in order to manipulate the steering rack position without torque feedback to the steering wheel. To this effect, the power-steering actuator is used to implement a feed-forward control in order to compensate for the inertial effect introduced by the angle superposition. A rudimentary steering system model is used to derive the relevant transfer functions and assemble the control law for the superposition actuator. Experimental results of a research project at the BMW Group are included.

MODELING OF HIGH-SPEED FINISH MILLING PROCESS USING SOFT COMPUTING

2010 ◽  
Vol 01 (03) ◽  
pp. 405-420 ◽  
Author(s):  
B. SUREKHA ◽  
PANDU R. VUNDAVILLI ◽  
M. B. PARAPPAGOUDAR ◽  
K. SHYAM PRASAD
Keyword(s):  
Neural Network ◽  
Soft Computing ◽  
High Speed ◽  
Transfer Functions ◽  
Forward Modeling ◽  
Milling Process ◽  
Rule Base ◽  
Machining Parameters ◽  
Layer Transfer ◽  
Hidden Layer

In the present study, forward modeling of high-speed finish milling process has been solved using soft computing. Two different approaches, namely neural network (NN) and fuzzy logic (FL), have been developed to solve the said problem. The performance of NN and FL systems depends on the structure (i.e. number of neurons in the hidden layer, transfer functions, connection weights, etc.) and knowledge base (i.e. rule base and data base), respectively. Here, an approach is proposed to optimize the above-mentioned parameters of NN and FL systems. A binary coded genetic algorithm (GA) has been used for the said purpose. Once optimized, the NN and FL-based models will be able to provide optimal machining parameters online. The developed approaches are found to solve the above problem effectively, and the performances of the developed approaches have been compared among themselves and with that of the results of existing literature.

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