Header Assignment block error in ROS Toolbox: Header Assignment/Current Time' error occurred

I'm currently setting up a UAV simulation with a LiDAR and an RGB camera. My 3d animation scene is perfectly running and simulating. Now, I want to take some of the lidar data and camera data, and publish it over ROS (not ROS2), to a specific topic. I've registered my customMsg structure, which is:

std_msgs/Header header

uint32 seq

time stamp

string frame_id

uint64 timebase

uint32 point_num

uint8 lidar_id

uint8[3] rsvd

livox_ros_driver/CustomPoint[] points

uint32 offset_time

float32 x

float32 y

float32 z

uint8 reflectivity

uint8 tag

uint8 line

The Simulink model diagram should help understanding the setup.

The MATLAB function simply populates the Points array, and then outputs it to the Points field in the bus assignment block. The blank message has the above mentioned structure. In header assignment, i checked set timestamp, and i set the frame_id as camera_init, which is what I found from a bag file of data, which I'm essentially attempting to replicate. The topic is /livox/lidar, and I simply want to publish my data there, or just generally test it.

Now that i've given enough context (better safe than sorry), the error occurs in the header assignment block. The error is:

MATLAB System block 'UAV_LIDAR_HASAN_TEST/Header Assignment/Current Time' error occurred when invoking 'getOutputDataTypeImpl' method of 'ros.slros.internal.block.CurrentTime'. The error was thrown from '

'/usr/local/MATLAB/R2024b/toolbox/ros/utilities/+ros/+slros/+internal/+bus/Util.m' at line 307

'/usr/local/MATLAB/R2024b/toolbox/ros/utilities/+ros/+slros/+internal/+block/CurrentTime.m' at line 286

'/usr/local/MATLAB/R2024b/toolbox/ros/utilities/+ros/+slros/+internal/+block/CurrentTime.m' at line 215

'/usr/local/MATLAB/R2024b/toolbox/simulink/ui/studio/config/m/+SLStudio/StartPauseContinue.p' at line 0

'/usr/local/MATLAB/R2024b/toolbox/simulink/ui/studio/config/m/+SLStudio/ToolBars.p' at line 0'.

Caused by:

Invalid Simulink object name: 'untitled'.

The block diagram 'untitled' is not loaded

I've tried restarting MATLAB and Simulink. I always use rosinit and generally can't seem to find why this error is occuring. I can't open the header block subsystem as well as it says hidden? I may be wrong here, just can't understand the cause. I see error is with the Current Time block, and that the block diagram "untitled" is not loaded, but it makes no sense to me. I know the Current Time block should get the ros system time, so i don't know if maybe its unable to get it. My model itself is saved, and there's no unconnected blocks or ports.

This issue is currently also occuring in the default "ros/RosHeaderAssignmentBlockExample", as well as in my own simulation. So I figure it has to be some sort of global issue?

Can anyone help? Am I missing something really basic? Sorry if the issue's really small. My environment is Ubuntu 20.04, and Ros Noetic.

Answer 1

[Josh Chen]

Hello Hasan,

Thanks for bring this issue to our attention. This is a known bug caused by an internal infrastructure update. We are actively working on addressing this issue in future updates.

Before the update is available, can you try the following options and see if it works?

1. Get the latest update of MATLAB
2. Save and close the model, then reopen the model. After reopening the model, use Ctrl+D to update the model

If none of these resolve the issue, would you be able to create some simple dummy model and share here so we can take a look on our end?

Thanks,

Josh

[Hasan]

Hey Josh! Thanks for the reply. I checked, and there was R2024b Update 2 available. I updated and tried again, and it's working. I waited just incase and tested it in different ways, and so far so good. Thanks so much! I appreciate the fast reply.