Project: 37 module Flat Hexagonal Detector Array - OUWECAD/MOWE GitHub Wiki

##Table of Contents Project Description
Results

Project Description

The 37-module flat hexagonal array shown below was constructed as an example of arrays with large spatial coverage. Its combined FoV cross-section area is 299.8 cm^2 at the convergence distance (dR=8.66mm from the array surface.) Maximum measured scan rate reached 794 Hz when reporting back 74 bytes per scan. Further tuning as well as increasing the serial ports baudrate can push the scan rate well above 1 KHz. Each module takes a 12-bit ADC sample and reports it back in a 16-bit value, which renders the four most significant bits (MSB) redundant (They can be used for signaling or data integrity.) The array measures 21 cm from corner to corner, weighs about 75 grams, and costs less than $200 to build.

Serial port baudrate should be set to 3000000 and data is read from module 1. The array topology is available in the subfolder /Firmware/Inc/37_flat_rx.h.

37_flat1 37_flat2 37_flat3 37_flat4 37_flat5

The array electrical backbone (built out of DMA streams) is shown in below. Module 1 is the master.

37_flat_DMA

Results

The Matlab file 37_flat.m is used to read captured data offline and plot graphs and record videos. The intensity values can be equalized to compensate for sensitivity variations between modules or can be left as is. Also, if some modules have different load resistors, this can be corrected in the Matlab file as is the case with module 1. The following video recordings represent various experiments using the flat all-receiver array. Click on each picture to open the video in YouTube.

37_flat_pas_uneq

  • 37_flat_pas_eq: A passive object crossing the array (equalized version).

37_flat_pas_eq

37_flat_act1_uneq

37_flat_track_uneq

  • 37_flat_act3_uneq: Two active objects with different intensities moving across the array.

37_flat_act3_uneq

  • 37_flat_speed: Speed estimation of an active object (1.5m/sec).

37_flat_speed