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This paper proposes a control method to remotely operate cooperative multiple heterogeneous slave unmanned aerial vehicles (UAVs) via a single master robot to perform different tasks on different targets in one mission. The UAV team is formed by different automated aircrafts. They are equipped with a vehicle-task-target pairing algorithm to be assigned their proper tasks and targets when moving in a leader-follower formation to track and perform assigned targets and tasks, respectively. The proposed leader-follower formation control method is modified based on a potential field algorithm to guide the UAV team or sub-team. In the UAV team, only a single leader vehicle is teleoperated by a human operator while all other follower vehicles autonomously form the formation regarding the leader movement. Therefore, the number of long distance transmission links between UAVs is reduced to minimize the possibility of occurrences of large communication delays.

Legislation world-wide has made it necessary to find ways to control the level of engine emissions and reduce the damage to our environment. Increasing restrictions have made the elimination of zinc dithiophosphates from crankcase oils and increasing the effectiveness of catalytic converters viable options. Lead and phosphorus containing compounds in the exhaust are known catalyst poisons that shorten the life of current automotive catalysts. Unleaded fuel has successfully resulted in a reduction of harmful emissions due to the fuel. Current government and industry research is actively pursuing replacement of phosphorus additives with phosphorus free additives. Several phosphorus-free oils were developed and are evaluated in bench tests in this study. Test comparisons with phosphorus- containing oils demonstrated satisfactory oxidation stability and wear performance of the phosphorus free oils.

Efficient aftertreatment management requires accurate sensing of both particulate filter soot and ash levels for optimized feedback control. Currently a combination of pressure drop measurements and predictive models are used to indirectly estimate the loading state of the filter. Accurate determination of filter soot loading levels is challenging under certain operating conditions, particularly following partial regeneration events and at low flow rate (idle) conditions. This work applied radio frequency (RF)-based sensors to provide a direct measure of the particulate filter soot levels in situ. Direct measurements of the filter loading state enable advanced feedback controls to optimize the combined engine and aftertreatment system for improved DPF management. This study instrumented several cordierite and aluminum titanate diesel particulate filters with RF sensors. The systems were tested on a range of light- and heavy-duty applications, which included on- and off-road engines.

Radio frequency (RF)-based sensors provide a direct measure of the particulate filter loading state. In contrast to particulate matter (PM) sensors, which monitor the concentration of PM in the exhaust gas stream for on-board diagnostics purposes, RF sensors have historically been applied to monitor and control the particulate filter regeneration process. This work developed an RF-based particulate filter control system utilizing both conventional and fast response RF sensors, and evaluated the feasibility of applying fast-response RF sensors to provide a real-time measurement of engine-out PM emissions. Testing with a light-duty diesel engine equipped with fast response RF sensors investigated the potential to utilize the particulate filter itself as an engine-out soot sensor.

The operational life and reliability of internal combustion (I.C.) engines are limited by the breakdown of the engine components due to wear under boundary lubricated conditions. It is very advantageous to know the condition of an engine and its components without disassembling the engine for examination. This paper employs the chemical and physical analysis of used synthetic crankcase oil to predict the condition of the lubricant and engine wear components during continuous operation. In this research, it is concluded that the iron content of the used oil can be used to define the oil drain interval to optimize oil use in the engine and minimize the wear process. Using an engine dynamometer, the optimum oil drain interval for a fully synthetic 15W50 was found to be 11,000 km.

This paper summarizes the results of both the preliminary studies and the initial cycle tests of a unique type of IC engine capable of operating in the absence of an atmosphere. This engine has been designed specifically for use in the general space program, and it is intended to satisfy requirements of high power to weight ratio, reliability, compactness, and short development time. The history of the en-engine's development is discussed together with problems encountered in the study. However, primary emphasis is on the recently conducted cycle tests.