A Conjugate Gradient-Based BPTT-Like Optimal Control Algorithm With Vehicle Dynamics Control Application

The paper presents a gradient-based algorithm for optimal control of nonlinear multivariable systems with control and state vectors constraints. The algorithm has a backward-in-time recurrent structure similar to the backpropagation-through-time algorithm, which is mostly used as a learning algorithm for dynamic neural networks. Other main features of the algorithm include the use of higher order Adams time-discretization schemes, numerical calculation of Jacobians, and advanced conjugate gradient methods for favorable convergence properties. The algorithm performance is illustrated on an example of off-line vehicle dynamics control optimization based on a realistic high-order vehicle model. The optimized control variables are active rear differential torque transfer and active rear steering road wheel angle, while the optimization tasks are trajectory tracking and roll minimization for a double lane change maneuver

Determination of free energies on a simulation model

Social free energy was recently introduced as a measure of social action obtainable from a given social system, without changes in its structure. In this article its relation with physical free energy for a toy-model of interacting agents is analysed. Values of the social and physical free energies are equivalent for the case of quasi-stationary state of toy-model of interacting agents. Classification-ACM-1998: J.4 [Computer Applications]; Social and behavioral sciences - Sociologysocial free energy, social entropy, social systems, agent, modelling

Mediated Character of Economic Interactions

Abstract: Economic interactions are conducted between economic agents - individuals and collectives, through exchange of natural or artificial entities - goods, services and money, in a myriad of combinations. In this article we adopt a microscopic point of view, concentrate on the exchanged entities, and extract their relevant attributes as seen from structurally simple economic processes. Following that, we approach the interpretation of the economic interactions with their mediated character emphasized. Mediators of the interaction are locally available environment units. They are locally recognized and appropriately interpreted in a given value set as goods and money. The overall intensity of economic interactions considered is related to mediators' spatial and temporal characteristics. Extracted characteristics of mediators and economic processes are compacted in the set of formal rules. The approach is connected with similar approaches in economy and physics

Heavy-Lift Multirotor Unmanned Aerial Vehicles Characterization and Sizing

In this paper, the characterization and sizing of heavy-lift multirotor UAVs are carried out. For this purpose, the electric multirotor UAV system is briefly described, and the parameters are carefully selected encompassing a wide range of UAVs regarding size and power. In the first phase, comprehensive experimental measurements are conducted for selected propulsion components. Through a systematic data acquisition process, a database for two series of electric propulsion units (low voltage and high voltage setups), is obtained. Using the presented identification procedure, the data is processed, and the characterization is completed in the following phase. Based on experimental data, a more accurate model of aerodynamic forces and torques and electric power was obtained, compared to previous approaches. In the final phase of this research, sizing of conventional heavy-lift multirotor configurations is carried out, where the diagonal, take-off mass, hovering power, and payload capacity are considered, and results are shown graphically. The proposed sizing steps enable further performance analysis to design a more efficient system, especially from the aspect of payload capacity

[Photograph 2012.201.B1038.0046]

Photograph used for a newspaper owned by the Oklahoma Publishing Company