Can multiple cameras be connected as slaves to a signal generator

[neufieldrobotics]

Can multiple cameras be connected as slaves to a signal generator

Yes, this should be doable. It is a feature we have added recently. You should be able to use the code in the branch called external_trigger. Hope this helps. Let us know if you have issues using it.

Cheers,
Vik

[mihir7714]

Thanks Vik. I am trying to build the external-trigger code but getting the following CMake Error.

Could not find a package configuration file provided by "trigger_msgs" with any of the following names:
trigger_msgsConfig.cmake
trigger_msgs-config.cmake

Where can the trigger_msgs package be found? Thanks

Try removing trigger_msgs from CMakeLists.txt under catkin required components (line 27). The idea is that if you have the package it would use it otherwise it won't.

[mihir7714]

Yes I did that, but it then gives me the following error:

/home/demo/catkin_ws/src/spinnaker_sdk_camera_driver/src/capture.cpp:1172:30: error: ‘sync_message_queue_vector_’ was not declared in this scope
if(img_q->empty() || sync_message_queue_vector_.at(cam_no).empty()){
^~~~~~~~~~~~~~~~~~~~~~~~~~
/home/demo/catkin_ws/src/spinnaker_sdk_camera_driver/src/capture.cpp:1182:43: error: ‘sync_message_queue_vector_’ was not declared in this scope
if (abs((int)img_q->size() - (int)sync_message_queue_vector_.at(cam_no).size()) > 100){

Invoking "make -j8 -l8" failed

This is super wierd. I just downloaded the repo fresh on a computer and removed line 27 from CMakeLists and was able to compile fine. Also, sync_message_queue_vector_ is declared in the capture.h file, so that error doesn't make sense. Can you try starting from a clean slate. commenting line 27 and compiling.

[mihir7714]

Yes tried it. Works! Thanks Vik.
I am trying to generate live images through "rqt" but no images are seen, gray screen. While it says ACQUISITION on the terminal there are no updates after that to show images are being taken.
There is a particular warning about trigger_msgs.

Pasting it below, is this expected to work despite that warning? is one of the acquisition.launch parameters configured wrong?

process[acquisition_node-2]: started with pid [25670]
[ INFO] [1584371320.197257931]: [ OK ] USB memory: 1500 MB
[ INFO] [1584371320.197986024]: *** PARAMETER SETTINGS ***
[ INFO] [1584371320.198020138]: ** Date = 20200316
[ INFO] [1584371320.198304735]: Save path set via parameter to: /home/demo
[ INFO] [1584371320.198337380]: Camera IDs:
[ INFO] [1584371320.198645886]: 17416721
[ INFO] [1584371320.198668764]: 17416723
[ INFO] [1584371320.198964673]: Camera Aliases:
[ INFO] [1584371320.198986965]: 17416721 >> cam0
[ INFO] [1584371320.198997755]: 17416723 >> cam1
[ INFO] [1584371320.199284913]: External trigger: true
[ WARN] [1584371320.199306197]: Using 'external_trigger'. Trigger msgs package not found, will use machine timestamps
[ INFO] [1584371320.199575928]: Unique time stamps for each camera: false
[ INFO] [1584371320.199814226]: color set to: true
[ INFO] [1584371320.200046860]: Exporting images to ROS: true
[ INFO] [1584371320.200267405]: Showing live images setting: true
[ INFO] [1584371320.200450630]: Showing grid-style live images setting: true
[ INFO] [1584371320.200704065]: Max Rate Save Mode: false
[ INFO] [1584371320.200906774]: Displaying timing details: true
[ INFO] [1584371320.201119020]: No. of images to skip set to: 20
[ INFO] [1584371320.201335687]: Init sleep delays set to : 1.00 sec
[ WARN] [1584371320.201547525]: 'fps' Parameter not set, using default behavior: fps=20.00
[ INFO] [1584371320.201755497]: 'exposure_time'=0, Setting autoexposure
[ INFO] [1584371320.201965135]: 'target_grey_value'=0, Setting AutoExposureTargetGreyValueAuto to Continuous/ auto
[ INFO] [1584371320.202170359]: Binning set to: 2
[ INFO] [1584371320.202378549]: Using Software rate control, rate set to: 30
[ INFO] [1584371320.202586208]: Saving images set to: 0
[ INFO] [1584371320.202767523]: save_type set as: bmp
[ INFO] [1584371320.203254184]: tf_prefix set to:
[ INFO] [1584371320.204002868]: Camera coeffs not provided correctly, camera info messges will not be published.
[ INFO] [1584371320.204027871]: Creating system instance...
[ INFO] [1584371320.205332037]: Retreiving list of cameras...
[ INFO] [1584371321.269132461]: Numer of cameras found: 2
[ INFO] [1584371321.269229690]: Cameras connected: 2
[ INFO] [1584371321.269373965]: -17416721
[ INFO] [1584371321.269458658]: -17416723
[ INFO] [1584371321.310479005]: Dynamic Reconfigure: Level : 4294967295
[ INFO] [1584371321.311123284]: *** FLUSH SEQUENCE ***
[ INFO] [1584371321.311143590]: Initializing cameras...
[ INFO] [1584371323.790295136]: Deinitializing cameras...
[ INFO] [1584371324.204446857]: All cameras deinitialized.
[ INFO] [1584371326.204972989]: Initializing cameras...
[ INFO] [1584371328.389388063]: *** ACQUISITION ***

First step to debug is making sure that your hardware setup works with SpinView with the same external trigger. Have you tried that?