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Currently, several 1D physics-based high-fidelity engine simulation software packages exist and provide reasonably accurate predictions of engine performance. However, most of the current high-fidelity engine simulation packages are developed in conventional programming languages and cannot be directly implemented in today's predominant MATLAB/Simulink simulation environment. In an effort to develop a MATLAB/Simulink-based engine simulation package, a high-fidelity 1D physics-based engine simulation model is currently being developed at The University of Alabama. The proposed model library includes various functional blocks capable of being connected in a logical manner to form a full engine system. Some of the functional blocks include a 1D unsteady flow section, cylinder valve, throttle, flow junction, cylinder, and engine dynamics. In this paper, preliminary simulation results are presented as well as descriptions of the functional blocks.

Hydraulic excavators perform numerous tasks in the construction and mining industry. Although ground grading is a common task, proper grading cannot easily be achieved. Grading requires an experienced operator to control the boom, arm, and bucket cylinders in a rapid and coordinated manner. Due to this reason, automated grade control is being considered as an effective alternative to conventional human-operated ground grading. In this paper, a path-planning method based on a 2D kinematic model and inverse kinematics is used to determine the desired trajectory of an excavator's boom, arm, and bucket cylinders. Then, the developed path planning method and PI control algorithms for the three cylinders are verified by a simple excavator model developed in Simulink®. The simulation results show that the automated grade control algorithm can grade level or with reduced operation time and error.