Summary: | 碩士 === 國立臺灣大學 === 土木工程學研究所 === 101 === This research aims at developing a motion planning and coordination method for commonly-used construction machines, including excavators, mobile cranes, trucks and tractor trailers. This method includes four steps: (1) model development, (2) C-Space (configuration space) construction, (3) path finding and (4) machines coordination The first step is to categorize the construction machines into three types, including wheel, track and chain. This allows further simulating the behaviors of the machined using mathematics equations. The second step is to construct the configuration space (C-Space) for the machines. This transfers a complicated geometric problem in the real-world space (Cartesian space) into an artificial space, which can simplify the following path-planning process. The third step is to compute the collision-free paths in the C-Space and transfer them into Cartesian space. The fourth step is to coordinate the paths of the machines to avoid possible conflicts. I implemented a computer program to demonstrate and validate the four-step method. The computer program simulated and visualized the construction machines motion by using a graphic engine Microsoft XNA and a physics engine Nvidia PhysX. A virtual construction site is constructed for testing the efficiency of the developed method, the working areas are narrow, only allow the pass of crawler crane or similar machines. On the virtual site, I designed a case in which two construction machines simultaneously move in a construction site and have the possibility of collision. From the test, I found that the calculation for path planning and coordination of the machines spend is approximate one second, and the construction of C-Space require 10.45 seconds for wheel and track machines, and 45.21 seconds for chain machines. The result of this research can successfully building model and C-Space of construction machines and generate a collision free path for multiple machines. This research provides an effective method for planning construction machines, and can be used for practical case in construction planning.
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