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The roll centre (RC) is a core parameter for vehicle lateral dynamics and control, which can be obtained via suspension geometry configuration or suspension kinematics and compliance (K&C) test. Ho...

A tri-copter unmanned aerial vehicle (UAV) with individually tilted main wings for various flight maneuvers is presented. In contrast to conventional tilt wing UAVs, thrust vectoring and control of the directions of main wing surfaces are attained by tilting main wings individually. Such individually tilted main wings allow more efficient maneuvers of the UAV. Even though the UAV is a tri-copter, it can compensate the reaction torque created by the tail motor by the individual control of the main wings. Few publications have appeared in the literature, dealing with tri-copter UAV with individually tilted main wings. Dynamic model of the UAV is established via the Newton-Euler formulation and effect of individual wing control is examined. The PID controller and PI controller for control of flight maneuvers are implemented and used for simulations and experiments. Results of simulations and experiments are presented for validation of flight performance of the UAV, including the roll rate 80% larger than that of the conventional UAV with ailerons as control surfaces.

The current wake turbulence separation standard given in ICAO DOC4444 was formed many years ago, and it limits the airport capacity while ensuring safety. By analyzing the current RECAT separation standards in Europe and the United States, based on the knowledge of wake vortex behavior together with lots of measured data, the methods of aircraft categories classification were studied systematically, and the parameters termed as the initial circulation, dimensionless relative circulation, the induced rolling moment coefficient and the Required Actual Roll Rate (RARR) were given to consider the severity and safety of wake vortex encountering. Then a new standard named RECAT-CN is proposed by the authors to obtain more balanced and reasonable results in safety domain.

This paper presents a method that designs dual extended Kalman filters (EKFs) for active roll control. There are two Kalman filters: state and parameter estimators. The roll angle of a vehicle is estimated by the state estimator with roll rate measurement. It has been well known that the recursive least square (RLS) or parameter estimation scheme can be represented with Kalman filter. Using the fact, the parameters of a vehicle model are estimated by the parameter estimator using the estimated roll angle. Simulation and experiments are done to validate the proposed dual EKFs for active roll control.

It is crucial for Indonesia as an agricultural country to have its own satellite image to be utilized in Indonesia's resources monitoring. LAPAN-A3 satellite data has been studied for earth observation and can be utilized for monitoring paddy fields, built-up areas, forests, rivers, fishponds, shrubs, sea, agricultural lands, and bare soils. But, as a sun-synchronous satellite, LAPAN-A3 has demerit of little revisit time for one specific area. Therefore, off-nadir imaging becomes one essential trait of the satellite to increase target monitoring from 17 times to 71 times in a year. This paper aims to organize the development process of off-nadir strategy in acquiring target image in Indonesia. With two kinds of off-nadir maneuver, inertial pointing maneuver and wheel speed maneuver, LAPAN-A3 satellite can conduct off-nadir imaging up to 34.5° roll angle maneuver. Furthermore, wheel speed maneuver with roll angle and roll rate approach presents the improvement in time efficiency of the maneuver, from 1 hour and 35 minutes executing time in inertial pointing to 25 minutes in wheel speed maneuver, making it become promising candidate for time-constraint off-nadir imaging.

Narrow vehicles have many possible qualities then the normal track width cars. However, the main disadvantage of the narrow vehicles is their tendency to roll over. That is why the active roll mitigation system seems to be necessary. Torque vectoring has huge impact on vehicles steering characteristics. The paper contains a description of simulation models. The three degree of freedom model (3DOF) of a vehicle as a development of former bicycle model is presented as an appropriate model for the test subject. The rolling stability is described. The basic roll detection system is presented and its usefulness is discussed. Another approach based on the roll angle and roll rate is presented. The paper contains the description of a tested narrow car, results of preliminary tests and simulations results compared with road tests results of narrow vehicle. The usefulness of a 3DOF vehicle model to describe the movement of the vehicle was tested. The usefulness of roll angle calculation using 3DOF model in roll mitigation system at narrow car is discussed.

The objectivity of the customers' feasibility is biased with the interest of the targeted credit that they are assigned to achieve. In addition, it remains an obstacle forsmall and medium class banks to be dependant on the long historical credit data of each customer to determine the credit-value loss (CKPN). This study uses a method of a qualitative case study with structured stages for determining the formation of credit-value loss (CKPN) with creditrisk+ model. The purpose of this study is to reveal the accounting practice of establishing CKPN with creditrisk+ model. The results show that the ATMR method caused BPR banks to provide a very large recovery fund when compared with CreditRisk+ method. Other findings reveal that the approach of ATMR is not maximized in producing accurate measure of credit risk and in accordance with the actual condition. This study contributes to providing an alternative to the determination of CKPN in addition to using ATMR and roll rate analysis model by the banks. For the regulators and professional organizations of the Indonesian Institute of Accountants, they can use it as sources of information to evaluate the application of PSAK 55, especially in determining the CKPN.