Research And Application Of Multi-core Heterogeneous Structured Light 3D Measurement System

Structured light is a non-contact 3D measurement technology known for its high accuracy,and it has found diverse applications in various fields.However,the existing structured light systems rely mainly on general-purpose PCs,which limit their deployment flexibility and portability,thereby restricting their applications.To overcome these limitations,this thesis proposes a multi-core heterogeneous system that enhances the flexibility,portability,and speed of structured light 3D measurement systems.The main works of this thesis are as follows.To meet the requirements of efficiency,integration,universality,and flexibility,a multi-core heterogeneous architecture consisting of three different cores: a Linux-based CPU,a bare-metal CPU,and an FPGA,is proposed and designed.This hierarchical and structurally flexible architecture can be easily integrated with various optical devices using a range of general interfaces.Additionally,we address the bottleneck problem of data communication between inter-cores by designing a well-designed multi-core data communication scheme.The core devices are carefully selected to construct the final structured light 3D measurement system.Peripheral hardware systems,such as the power module,HDMI interface module,and SD card module,are also designed for seamless integration.At last,the final printed circuit board is designed and rigorously tested to ensure optimal performance and reliability.We have well-designed procedures for two different CPUs,i.e.,CPU(Linux)and CPU(Bare Metal),ensuring their synchronization and cooperation.Moreover,various optimization techniques are employed to take full advantage of FPGA parallel pipeline calculation.More specifically,the entire processes for structured light algorithm,including phase demodulation,unwrapping,and triangulation,are accelerated.Additionally,a structured light offline calibration algorithm based on the local homograph matrix calibration of the projector is realized as well.On the basis of the works above,further experiments are tested for the proposed multi-core heterogeneous structured light system.Experimental results demonstrate that the proposed system 1)effectively measures complex objects,2)achieves comparable measurement precision(0.1948mm)while the processing speed is 11 times that of PC.