Tilt Control System Research Articles

Failure Effects of Tilting Control System on Train

The mechanical-electrical coupled dynamic model of the tilting train is established in order to study the failure effects of tilting control system. Four kinds of movement of the driving actuator are compared, specifically including: normal tilting, no tilting, insufficient tilting and tilting on the contrary. The results has shown: when the tilting is insufficient or no tilting, the influence to the dynamic is small, the curve-passing speed reduces obviously; when tilting on the contrary, the dynamic performances of front bogie become worse and the curve-passing speed decreases much more.

410 動圧軸受血液ポンプのための傾き制御機構の研究開発(OS5-(4)オーガナイズドセッション《ライフサポートにおける工学技術》)

410 動圧軸受血液ポンプのための傾き制御機構の研究開発(OS5-(4)オーガナイズドセッション《ライフサポートにおける工学技術》)

Development and Experimental Evaluation of a Tilt Stability Control System for Narrow Commuter Vehicles

This paper concentrates on development and experimental investigation of a compound control system designed for tilt stability of a narrow commuter vehicle. The control system is a combination of three different types of control schemes: Steering Tilt Control (STC) system, Direct Tilt Control (DTC) system and Tilt Brake system. These schemes utilize different types of actuators and offer complementary advantages over different ranges of operating speeds. The design of the control system is discussed. Then the combined STC-DTC system is first validated by running standard vehicle maneuver experiments such as turns and lane changes. The performance of the Tilt Brake algorithm is then verified for different low speed maneuvers. The feasibility of a stand alone DTC system is also experimentally investigated. Finally different experimental results are presented to demonstrate the effect of desired tilt angle definition on the handling of a narrow tilting vehicle.

Study on intelligent baby carriage with power assist system and comfortable basket

In Japan, lightweight and easy-to-fold baby carriages are commonly used because a parent has to hold both the baby and its carriage while ascending or descending a flight of stairs. Since families commuting by private automobiles are increasing, there is a demand for carriages with high functionality. In this study, an intelligent baby carriage equipped with an advanced electro-hybrid power assist system that uses in-wheel-type motors is experimentally developed. This system assists the parent in lifting the carriage onto a sidewalk by detecting the edge of the sidewalk using an ultrasonic distance sensor. The carriage also has the following features: a tilt control system that keeps the basket in a horizontal position even on a slope, and a heartbeat simulator that provides comfort to the baby in the basket by simulating the heartbeat of the parent. The effectiveness of the proposed carriage is confirmed by performing experiments.

1203 流量比例弁を用いた空気ばね車体傾斜制御システムの開発(OS1-1:乗心地・快適性,OS1:交通・物流システムの高速化,利便性,快適性の向上,オーガナイズド・セッション(OS),第18回交通・物流部門大会(TRANSLOG2009))

1203 流量比例弁を用いた空気ばね車体傾斜制御システムの開発(OS1-1:乗心地・快適性,OS1:交通・物流システムの高速化,利便性,快適性の向上,オーガナイズド・セッション(OS),第18回交通・物流部門大会(TRANSLOG2009))

Development of a tilting system for electric multiple unit to speed up on conventional lines

An advanced tilting system for KTT (Korean Tilting Train) was developed and a performance test of the system has been completed. KTT has been constructed to speed up and promise a significant enhancement in service quality on a conventional line. KTT is an electric multiple unit composed of 6 cars running at the design speed of 200 km/h. The tilting system is the core technology of KTT and combined with the conventional bogie system. It has a self-steering mechanism and a swing link. The self-steering mechanism of Z-bar type is free to rotate on the curve and stable to run on a straight line. The swing link mechanism of the bolster enables the carbody to tilt up to 8°. A tilting control system detects a curve with sensors and commands the electro-mechanical actuators to move the bolster through the computer network system. GPS collaborates with the tilting system to perceive the curve previously and enables gradual tilting so as not to violate passenger comfort. The performance of the tilting system has been verified by a trial test running of KTT on a commercial conventional line. The tilting system is ready for commercial use.

Reduced-order robust tilt control design for high-speed railway vehicles

This paper presents a study of model reduction techniques, as well as controller reduction via closed-loop considerations in designing robust tilt controllers to improve the curving performance of high-speed railway vehicles. The schemes make exclusive use of local practical signal measurements, i.e. sensors mounted on the current passenger coach. The fundamental problem related to straight-forward classical nulling-feedback control is presented, and the commercially used command-driven with precedence scheme is introduced. Simulation results and an appropriately defined tilt control system assessment method are employed for illustrating the efficacy of the reduced-order robust tilt controller.

A fundamental investigation of tilt control systems for narrow commuter vehicles

One way of addressing traffic congestion is by efficiently utilizing the existing highway infrastructure. Narrow tilting vehicles that need a reduced width lane can be part of the solution if they can be designed to be safe, stable, and easy to operate. In this paper, a control system that stabilizes the tilt mode of such a vehicle without affecting the handling of the vehicle is proposed. This control system is a combination of two different types of control schemes known as steering tilt control (STC) and direct tilt control (DTC) systems. First, different existing variations of both STC and DTC systems are considered and their shortcomings analysed. Modified control schemes are then suggested to overcome the deficiencies. Then a new method of integrating these two control schemes that guarantees smooth switchover between the controllers as a function of vehicle velocity is proposed. The performance of the proposed STC, DTC, and integrated systems is evaluated by carrying out simulations for different operating conditions and some experimental work. The design of a second-generation narrow tilting vehicle on which the developed control system has been implemented is presented.

Study on Car Body Tilting System Using Variable Link Mechanism (2nd Report, Tilting Control Design Based on the Strategy of Perfect Tilting Condition)

This paper aims to analyze fundamental dynamic characteristics of tilting railway vehicle using variable link mechanism for compensating both lateral acceleration that passengers feel and wheel load imbalance between inner and outer rails. Theoretical analysis is conducted to find “Perfect Tilting Condition” that is a geometric parameter set of link mechanism that can provide both zero lateral acceleration and zero wheel load imbalance simultaneously. This perfect tilting condition can be realized by changing the variable length of link mechanism so that this tilting control system is a kind of semi-active control. To change the length of link mechanism on curved section, feedforward + feedback optimal control theory is applied to the vehicle body tilting system with a developed variable link mechanism presented in 1st report. From computer simulation and experiment using a scale model, it is clarified that the proposed tilting control is effective to suppress both over-centrifugal acceleration and wheel load imbalance.

Modeling and simulation of hydraulic components for passenger cars

Passenger car suspensions contain a number of hydraulic components, such as dampers, hydraulic rubber mounts, power steering and active suspension units. Modeling and simulation of these hydraulic components is reviewed and further developed on the basis of one-dimensional flows represented in the time domain, which is an effective and reliable approach for the design and analysis of automotive fluid power systems. The components of suspension systems are assembled by multi-port connectors for numerical analysis. Then, the solution by standard integration codes may result in fluid mass losses, which do not exist in reality. Therefore, an implicit integration code conserving the fluid mass is presented. The validated hydraulic component model blocks can be exported to a wide range of simulation programs without encountering problems. An active tire tilt control (ATTC) system is presented in detail. The deployment of automotive fluid power simulation allows for suspension system and vehicle dynamics design in virtual reality before a prototype vehicle is built. It is shown that accurate component models are required as a sound basis for the process chain of modeling, validation, and parameter identification, which results in full vehicle simulation. The excellent performance of ATTC vehicles has proven the quality of the predictive simulation results used for the performance optimization of this chassis system.

Development of Tilt Control System Using Electro-Hydraulic Actuators

To improve the performance and riding comfort of tilt-controlled vehicles, we developed a next-generation tilt control system that uses a position detecting system, a novel tilt pattern, high performance tilt actuators and other new technical elements. Under this system, the running train position is detected by curvature collation based on GPS signals and the tilting angle target pattern calculated to optimize the riding comfort evaluation index. The pattern thus created is called the JT pattern, according to which the tilt actuators are electro-hydraulically powered. Running tests have proved that low-frequency vibration causes train motion sickness has decreased as a result of this system.

IMPROVING THE TILT CONTROL PERFORMANCE OF HIGH-SPEED RAILWAY VEHICLES: AN LQG APPROACH

The paper discusses on the use of an optimal LQG control design to improve the vehicle curving performance at increased running speed, employing only local (rail vehicle-based) signal measurements. It addresses the fundamental problem related with straightforward feedback control, and introduces the commercially-used command-driven with precedence scheme. A combination of simulation results and, a recently proposed, tilt control system assessment method are utilised for assessing the overall performance of the tilt controller.

Study on Car Body Tilting System Using Variable Link Mechanism (Perfect Tilting Condition and Tilting Control)

This study aims to analyze fundamental dynamical characteristics of a tilting railway vehicle using variable link mechanism for compensating both lateral acceleration that passengers feel and wheel load imbalance between inner and outer rails. Theoretical analysis is conducted to find “Perfect Tilting Condition” that is a geometric parameter set of link mechanism that can provide both zero lateral acceleration and zero wheel load imbalance simultaneously. This perfect tilting condition can be realized by changing the variable length of link mechanism so that this tilting control system is a kind of semi-active control. To change the length of link mechanism on curved section, optimal control theory is applied to the vehicle body tilting system with a newly developed variable link mechanism. From computer simulation and experiment using a scale model, it is clarified that the proposed tilting system is effective to suppress both over-centrifugal acceleration and wheel load imbalance.

Dynamics of Narrow Tilting Vehicles

Narrow commuter vehicles can address many congestion, parking and pollution issues associated with urban transportation. In making narrow vehicles safe, comfortable and acceptable to the public, active tilt control systems are likely to play a crucial role. This paper concentrates on developing a dynamic model for narrow vehicles that can be used for the design and evaluation of active tilt control systems. The model has four degrees of freedom including lateral and tilt dynamics. The influence of gyroscopic forces due to rotating wheels and the influence of front wheel trail are included but secondary coupling effects are ignored so as to keep the model tractable. The model is used in this paper to understand the influence of vehicle tilt on the steering angle required for cornering, the desired tilt angle for any specified cornering maneuver and the influence of gyroscopic moments on transient tilting/cornering maneuvers. A study of the model equations also provides insight into how narrow vehicles can be designed so as to be self-stabilizing.

A201 Tilt Control System for Railway Vehicles Using Air Springs

In recent years, there has been growing needs to improve maximum speed on curved tracks. For this purpose, there are many tilting systems. However, vehicles that have special tilting mechanism, are much different from the ordinary ones and expensive. Thus we have developed a tilt control system that is constituted from the ordinary car body and bogie truck with less remodeling. Therefore the maximum tilting angle of this system is restricted to 2 degrees. This system mainly consists of a Controller, Air supply valves, Exhaust valves and Height sensors. The control method is programmed. The tilting operation is performed by the controller, which all data of the curved tracks have been memorized. The location of the vehicle is measured by the tachometer generator and the devices (ground coil) that are attached on the sleeper in order to correct running position. From several running test results, we confirmed that stationary lateral acceleration of car body was reduced by tilt control. The running stability and riding comfort was also adequate so the vehicle equipped with this system could run rapidly than the vehicle with the former restricted speed limit on curved track.

Tilt Control for Gyro-Stabilized Two-Wheeled Vehicles

Fully enclosed motorcycles could form the basis for extremely fuel and space efficient vehicles, but their inherent instability upon encountering even a momentary loss of traction renders them unsuitable for general use. It will be shown that a relatively simple tilt control system using a gyroscope to provide a tilt control moment is capable of stabilizing the vehicle at still stand or at speed on a very low traction surface. Furthermore, the system can achieve a coordinated turn on high traction surfaces. Since the gyro is an energy storage device, it can be used also in a hybrid system to provide extra power for acceleration and to recover some energy during braking. This relatively old idea should be reconsidered in light of the improved electromechanical devices, which have been developed recently for hybrid electric vehicles.

Hardware-in-loop Simulation of Railway Vehicles with Tilting and Active Suspension Systems

SUMMARYAn integrated model has been developed of a three-car tilting train. The model includes full non-linear wheel-rail contact modelling and significant suspension non-linearities. A realistic model of the tilt control system is also included. Simulations are presented of the effect of a number of system parameters on the behaviour of the tilting train. The development of a facility for hardware-in-loop testing of real tilt and active suspension control systems is discussed.

An Active Roll-Moment Control Strategy for Narrow Tilting Commuter Vehicles

SUMMARY An automatic tilt control strategy for a narrow commuter vehicle is described. Such a vehicle would be enclosed like a conventional car but would bank into turns like a motorcycle and so it would feel quite unconventional to drive. The proposed tilt control system uses the steering to tilt the car over like a motorcycle but this is augmented by actively generating a rolling moment about the pivot axis between the tilting upper body and non-tilting base. The provision of this active direct tilt control enables the vehicle to remain upright at low or zero speed and also permits the designer to fine tune the transient roll response. Although it appears complex the proposed tilting control relies on only a few simple sensor measurements, some modest, microprocessor based signal processing and low power, low bandwidth steering and tilt control actuators which might be derived from existing automotive components.

Control system studies of an active anti-roll bar tilt system for railway vehicles

This paper describes a theoretical study of an active anti-roll bar tilt control system for a railway vehicle. It presents the rationale behind body tilting, the advantages and disadvantages associated with body tilting and the key tilt control system requirements. The paper also describes the control modelling process and presents some simulation results from control system studies. A number of competing control systems have been designed and analysed, including both classical and optimal control strategies. The performance of the control systems for a variety of curves is considered, as well as their response to track irregularities. The results show that all the strategies provide good tilting performance, the optimal control approach being marginally better.

Curving Simulation of a Pendulum Vehicle.

A detailed dynamic model of the curving of a roller-type pendulum vehicle with tilting control was formulated and general equations of motion were derived, based on the use of a natural pendulum mechanism, an air spring secondary suspension system with height control, and an aircylinder-type car-body tilting control system. Digital simulations of curving for a representative example were made, introducing random track irregularities which were generated artificially from a track irregularity PSD. Effects of various track irregularities on lateral wheel-rail force and inner wheel unload were examined. It was shown that the maximum dynamic lateral wheel-rail force is effected mainly by lateral irregularity and that dynamic inner wheel unload increases due to superimposition of lateral irregularity, radius of curvature irregularity and cant irregularity.