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I have been looking at various options to obtain synchronized images from three or more cameras.

The options available for the TX2 are just simply out of my price range.

I accept that of course I will have some sort of delay since I am using a non-professional solution for this. So I am trying to come up with the best way to minimize this delay. Hopefully below 10ms.

Side note: I am also exploring getting a freelance engineer to design an FGPA and getting it printed.

For the time being I have several STM32 Blue-pill MCU's. My target camera is the ArduCAM Mini 5MP Plus.

This module uses SPI to interface an MCU with the image buffers, in single and burst reads.

Note: in the application note linked above they diagram a multi-camera setup, and an external hardware trigger.

My initial thoughts are as follows:

  1. Connect each camera module to a separate BluePill
  2. Synchronize the BluePills' clocks
  3. Have each BluePill burst read from the camera using SPI1 then place the buffer onto the SPI2 bus in slave mode
  4. this is where I get lost I need to somehow "stitch" the frames together either using a different MCU or the TX2 itself.

Motivation:

The reason for doing this is pretty clear. A well synchronized camera array starts at $600!

My use case for the cameras is a PoC of an autonomous go-kart for learning purposes. I currently have the following already working:

  1. 2D object detection and localization using YOLOv3 and pytorch
  2. 2D to 3D object localization from disparity maps generated by ConvNets using pytorch
  3. All my tests have been with benchmark datasets and images downloaded from google image searches

I think the next logical step is to put some cameras on the go-kart and start taking sample images to see how this'll all work in the real world.

Bonus question how is the hardware trigger actually used?

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  • \$\begingroup\$ You already have a a recent unresolved question on this topic at electronics.stackexchange.com/questions/462925/… . DO NOT REPOST. Instead, use edits to improve your existing question. Further it does not seem you've taken any steps yet to validate if the camera would meet your needs, even without the synchronization concern. \$\endgroup\$ – Chris Stratton Oct 16 at 2:33
  • \$\begingroup\$ @ChrisStratton I deleted the previous question. As far as the camera, I inspected the datasheet of the OV5642, which states that it's able to capture 30fps at 1080p, and 60fps at 720, which should meet my needs. It should work well in outdoor light conditions since it can be used as a field camera \$\endgroup\$ – Sam Hammamy Oct 16 at 2:58
  • \$\begingroup\$ @ChrisStratton However, as I am a beginner, I am certain you are correct. Can you please let me know why you think it is not suitable? \$\endgroup\$ – Sam Hammamy Oct 16 at 2:59
  • \$\begingroup\$ media.digikey.com/pdf/Data%20Sheets/OmniVision%20PDFs/… \$\endgroup\$ – Sam Hammamy Oct 16 at 2:59
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    \$\begingroup\$ @ChrisStratton The main concern, past having duplicate questions, is deleting answers. I don't think the comments have do much value that I'd force the deleted question to swap. \$\endgroup\$ – W5VO Oct 16 at 11:14

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