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The purpose of this paper is to introduce a co‐simulation method to study the ground maneuvers of aircraft anti‐skid braking and steering.

A virtual prototype of aircraft is established in the multibody system dynamics software MSC.ADAMS/Aircraft. The anti‐skid braking control model, which adopts the multi‐threshold PID control method with a slip‐velocity‐controlled, pressure‐bias‐modulated (PBM) system, is established in MATLAB/Simulink. EASY5 is used to establish the hydraulic system of nose wheel steering. The ADAMS model is connected to block diagrams of the anti‐skid braking control model in MATLAB/Simulink, and is also connected to the block diagrams of nose wheel steering system model in EASY5, so that the ground maneuvers of aircraft anti‐skid braking and steering are simulated separately.

Results are presented to investigate the performance of anti‐skid braking system in aircraft anti‐skid simulation. In aircraft steering simulation, the influence of two important parameters on the forces acting on the tires is discussed in detail, and the safe area to prevent aircraft sideslip is obtained.

This paper presents an advanced method to study the ground maneuvers of aircraft anti‐skid braking and steering, and establishes an integrated aircraft model of airframe, landing gear, steering system, and anti‐skid braking system to investigate the interaction of each subsystem via simulation.

The number of robot assembly systems in the UK is very low. One of the first to come on stream is helping Cam Gears assemble automobile steering units. Brian Rooks has been to investigate.

Steer-by-wire (SBW) system mainly relies on sensors, controllers and motors to replace the traditionally mechanical transmission mechanism to realize steering functions. However, the sensors in the SBW system are particularly vulnerable to external influences, which can cause systemic faults, leading to poor steering performance and even system instability. Therefore, this paper aims to adopt a fault-tolerant control method to solve the safety problem of the SBW system caused by sensors failure.

This paper proposes an active fault-tolerant control framework to deal with sensors failure in the SBW system by hierarchically introducing fault observer, fault estimator, fault reconstructor. Firstly, the fault observer is used to obtain the observation output of the SBW system and then obtain the residual between the observation output and the SBW system output. And then judge whether the SBW system fails according to the residual. Secondly, dependent on the residual obtained by the fault observer, a fault estimator is designed using bounded real lemma and regional pole configuration to estimate the amplitude and time-varying characteristics of the faulty sensor. Eventually, a fault reconstructor is designed based on the estimation value of sensors fault obtained by the fault estimator and SBW system output to tolerate the faulty sensor.

The numerical analysis shows that the fault observer can be rapidly activated to detect the fault while the sensors fault occurs. Moreover, the estimation accuracy of the fault estimator can reach to 98%, and the fault reconstructor can make the faulty SBW system to retain the steering characteristics, comparing to those of the fault-free SBW system. In addition, it was verified for the feasibility and effectiveness of the proposed control framework.

As the SBW fault diagnosis and fault-tolerant control in this paper only carry out numerical simulation research on sensors faults in matrix and laboratory/Simulink, the subsequent hardware in the loop test is needed for further verification.

Aiming at the SBW system with parameter perturbation and sensors failure, this paper proposes an active fault-tolerant control framework, which integrates fault observer, fault estimator and fault reconstructor so that the steering performance of SBW system with sensors faults is basically consistent with that of the fault-free SBW system.

THE landing gear of Anglo‐French Concorde is of conventional tricycle type. It consists of two main legs each fitted with a four‐wheel bogie (fig. 1) a nose leg fitted with a twin wheel unit (FIG. 2); a retractable tail bumper is also fitted. The main gear is manufactured by Hispano Suiza and the nose gear by Messier. The majority of the components are made from very high tensile steel (35NCD16) which is vacuum melted, treated to 270,000 lb./sq. in. and for which special anti‐corrosive measures have been taken.

BETWEEN May 18 and 26, airline experts from the United States, Australia, India, the Middle East, France and Great Britain gathered at Bristol and later at Toulouse in France to hear details of the progress which had been made with the Concorde supersonic airliner. This was the first time that representatives of the Concorde customer airlines had received this type of ‘on‐the‐spot’ technical presentation from British Aircraft Corporation, Sud‐Aviation, Bristol Siddeley Engines and S.N.E.C.M.A., and the whole venture has been described as highly successful. Not only did the customer airlines benefit from seeing, at the various plants, just exactly how the Concorde project is progressing, but they were also able to discuss in detail all engineering aspects of the aircraft with senior engineers of the Anglo‐French consortium. The manufacturers were also able to learn from the customers their views on particular aspects of the Concorde.

THE opening months of the last war were conducted in a very leisurely fashion because the expected disasters had not befallen us. Not until our armies were rescued from the beaches of Dunkirk did the stark realities of the situation percolate into the public mind. Once the facts were understood the whole country was galvanised into activity.

The paper aims to identify, prioritize and rank lean practices in the context of an Indian automotive component manufacturing organization using interpretive ranking process (IRP) and interpretive structural modeling (ISM) approaches.

Lean practices are identified from the literature. Then, two hierarchical models were are developed using two distinct modeling approaches – ISM and IRP with expert opinions from an Indian automotive component manufacturing organization to analyze the contextual relationships among the various lean practices and to prioritize and rank them with respect to performance dimensions.

In the study, the hierarchical structural models are developed using ISM and IRP approaches for an Indian automotive component manufacturing organization. In ISM-based modeling, lean practices can be categorized into five levels. Top priority should be given to the motivators followed by value chain, system/technology and organization centric practices. IRP model shows the dominance relationship among the various lean practices with respect to performance dimensions.

The models are constructed from the organizational standpoint to evaluate their impact to the implementation of lean manufacturing. The study leverages the organizations to prioritize limited resources as per the hierarchy. Managers get the inter-linkages and ranking of various lean practices, which leads to a better perspective for the effective implementation of lean. The structural models also assist management to assign proper roles to employees/departments for effective lean implementation.

There is hardly any structural model of lean practices in the literature for clustering, prioritizing and ranking of lean practices. The study fills this gap and develops the hierarchical models of lean practices through IRP and ISM approaches for an Indian automotive component manufacturing organization. The results from both approaches are compared for illustrating the benefits of one over the other.

The purpose of this paper was to solve the shortage of carrying energy in probing robot and make full use of wind resources in the Antarctic expedition by designing a four-wheel land-yacht. Land-yacht is a new kind of mobile robot powered by the wind using a sail. The mathematical model and trajectory of the land-yacht are presented in this paper.

The mechanism analysis method and experimental modeling method are used to establish a dual-input and dual-output mathematical model for the motion of land-yacht. First, the land-yacht’s model structure is obtained by using mechanism analysis. Then, the models of steering gear, servomotors and force of wing sail are analyzed and validated. Finally, the motion of land-yacht is simulated according to the mathematical model.

The mathematical model is used to analyze linear motion and steering motion. Compared with the simulation results and the actual experimental tests, the feasibility and reliability of the proposed land-yacht modeling are verified. It can travel according to the given signal.

This land-yacht can be used in the Antarctic, outer planet or for harsh environment exploration.

A land-yacht is designed, and the contribution of this research is the development of a mathematical model for land-yacht robot. It provides a theoretical basis for analysis of the land-yacht’s motion.

THE QUADRICYCLE CONFIGURATION landing gear chosen by the aircraft designers consists of a single wheel steerable nose leg, a twin wheel main leg, and two fully castoring single wheel outrigger legs at the wing tips. All retract aft into very confined spaces. Two standards of gear, normal and high speed, were designed and developed to meet the initial and final maximum landing speed requirements.