碩士 / 國立臺灣科技大學 / 電機工程系 / 98 / This thesis presents an embedded system based omni-wheeled robot control system to deal with autonomous path planning, odometry localization and reactive navigations. A Local-optimized rapidly-exploring random tree (LoRRT) is proposed to plan feasible navigation paths for unknown environments. At the same time, an artificial potential field (APF) approach is used by combining virtual obstacles to perform reactive navigations. Especially, the novel virtual obstacle approach effectively resolves the deadlock or oscillation situations when compared to conventional APF approaches. The proposed control system is implemented in terms of a hybrid-core system architecture which combines an Intel XScale-PXA270 based decision kernel and a field programmable gate array (FPGA) based motion control kernel. The FPGA controller is further developed using the system on a programmable chip (SoPC) technique to realize software/ hardware co-design architecture. The software module is implemented upon a NIOS II microprocessor, which is used to carry out the algorithms for kinematics based robotic odometry and motion controls. The verilog hardware modules are constructed to deal with serial communications, motor counters, motor controls and ultrasonic sensor collections so that the real-time signal processing and frequent I/O interrupts can be well arranged. On the other hand, the XScale-PXA270 embedded system is responsible of the algorithm implementations for LoRRT, APF, human-machine interface and laser range finder based map construction based on an embedded Linux operation system. Finally, a three omni-wheeled robot platform is fabricated in our laboratory. Several practical experiment results are discussed based on ground-truth evaluations to verify the performance of the proposed control system.
| Identifer | oai:union.ndltd.org:TW/098NTUS5442153 |
| Date | January 2010 |
| Creators | Shu-hao Chang, 張書豪 |
| Contributors | Chung-Hsien Kuo, 郭重顯 |
| Source Sets | National Digital Library of Theses and Dissertations in Taiwan |
| Language | zh-TW |
| Detected Language | English |
| Type | 學位論文 ; thesis |
| Format | 115 |
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