No abstract

High speed air transportation became the most common way of transportation, especially on the long distances. Though very fast and convenient, air transportation is a significant source of pollution: noise pollution and air pollution. The alternative to reduce emissions and noise pollution is to improve the operational performance of the aircraft. In this paper the new ground traction system for the aircraft LTO cycle based on an electric machine is proposed to reduce the pollution.

To hide personnel, equipments and vehicles modern battlefield uses many techniques such as natural and artificial obstacles (e.g. vegetation, and masking and netting, respectively). Even if the enemy would not use these methods there are some situations when conditions like bad weather may make difficult or impossible to visualize these obstacles. To overcome this inconvenience, a stabilized platform made of a complex sensor (visible and infrared camera) and a LASER radar is designed. This paper presents the results obtained in solving this complex problem by using complex data (image) processing not only to find the kind of targets described above, but also to identify them.

The constraints during the atmospheric ascent of the small NERVA rocket launcher are investigated, especially in regard to the limited flight envelope and mass optimization requirements. The usual flight ascent optimization faces in this case additional constraints, which must be solved with minimum losses of mass efficiency of the vehicle. A methodology of investigating the best ascent control laws is presented with emphasize on the second stage of the vehicle, regarding both the gas-dynamic controller system of the control unit and the accuracy of the inertial sensors of the self-guidance onboard system. The methodology is also focused on accommodating the high orbital insertion requirements of the gravity turn trajectory with a low-cost, highly secure flight controller system. Minimum technological modifications of the existing rocket propulsion system of the second stage are considered, which is a typical liquid propellant stage with aerodynamic and gas-dynamic attitude controls. Possible technological solutions are analyzed and compared regarding the accessibility of the ascent trajectories and optimal constrained solutions to the safety problem. The constraints are of safety, technological and international nature.

As a part of the ORVEAL project, a real scale laboratory model of the inertial platform for ADDASAT is developed by the joint ADDA and UPB teams, ensuring the capability of a three-axis attitude control demonstration in the ground laboratory that simulates weightlessness by low friction bearings. The study is part of the larger ADDA-UPB program for developing the low cost NERVA orbital system for applications in enhanced environmental policies and land resources surveillance. The ORVEAL research is granted by Romanian UEFISCDI financing authority.