title: A Real-Time Marker-Based Visual Sensor Based on a FPGA and a Soft Core Processor.
abstract: This paper introduces a real-time marker-based visual sensor architecture for mobile robot localization and navigation. A hardware acceleration architecture for post video processing system was implemented on a field-programmable gate array (FPGA). The pose calculation algorithm was implemented in a System on Chip (SoC) with an Altera Nios II soft-core processor. For every frame, single pass image segmentation and Feature Accelerated Segment Test (FAST) corner detection were used for extracting the predefined markers with known geometries in FPGA. Coplanar PosIT algorithm was implemented on the Nios II soft-core processor supplied with floating point hardware for accelerating floating point operations. Trigonometric functions have been approximated using Taylor series and cubic approximation using Lagrange polynomials. Inverse square root method has been implemented for approximating square root computations. Real time results have been achieved and pixel streams have been processed on the fly without any need to buffer the input frame for further implementation.
authors.affiliation: Department of Electronics and Information Engineering, Chonbuk National University, Jeonju 54896, Korea. hilaltayara@jbnu.ac.kr.
authors.forename: Hilal
authors.initials: H
authors.lastname: Tayara
authors.affiliation: Department of Electronics and Information Engineering, Chonbuk National University, Jeonju 54896, Korea. wcham@jbnu.ac.kr.
authors.forename: Woonchul
authors.initials: W
authors.lastname: Ham
authors.affiliation: Advanced Electronics and Information Research Center, Chonbuk National University, Jeonju 54896, Korea. kitchong@jbnu.ac.kr.
authors.forename: Kil To
authors.initials: KT
authors.lastname: Chong
keywords: FAST corner detection; FPGA; coplanar PosIt; image segmentation; visual sensors