RViz: How to Visualize a Voxblox Mesh as a MarkerArray?

Question

I am currently trying to run the test cow and lady dataset with Voxblox. The process appears to execute properly in the terminal, but I cannot view the mesh in RViz.

When I try to add the topic voxblox_node/mesh to RViz, the topic name is greyed out and I cannot add the topic. This topic is listed under "unvisualizable topics".

In Rviz, I tried creating a topic of type MarkerArray and manually typing in the topic name to add it. This does not work and I get the following error:

process[voxblox_node-2]: started with pid [18452]
[ INFO] [1523646547.806476760]: Opening /media/ubuntu/jetsontx2b/data/voxblox/data.bag
[ INFO] [1523646548.104770697]: Static transforms loaded from file.
T_B_D:
    0.971048      0.15701    -0.180038 -0.000432202
   -0.120915     0.973037     0.196415   -0.0522007
    0.206023    -0.168959      0.96385   -0.0341353
           0            0            0            1
T_B_C:1 0 0 0
0 1 0 0
0 0 1 0
0 0 0 1
[ERROR] [1523646548.172363508]: Client [/rviz_1523646021870801813] wants topic /voxblox_node/mesh to have datatype/md5sum [visualization_msgs/MarkerArray/d155b9ce5188fbaf89745847fd5882d7], but our version has [voxblox_msgs/Mesh/ca70fabcc211b61f795cb5e7c8210eb6]. Dropping connection.
[ INFO] [1523646549.056998208]: Updating mesh.

The Voxblox documentation states that the node voxblox_node publishes:

mesh of type visualization_msgs::MarkerArray. A visualization topic showing the mesh produced from the tsdf in a form that can be seen in RViz.

Why doesn't Rviz recognize mesh as a MarkerArray? What do I need to do to get Rviz to visualize /voxblox_node/mesh?

Thanks.

Answer 1

So the doc's were out of date. I just updated them as the mesh is actually of type voxblox_msgs::MeshBlock. Voxblox use to output a standard MarkerArray, however this form of visualization means you have to output the entire mesh every time any part of it changes. This meant when running on a robot and visualizing on a laptop we were saturating our wifi connection to display even relatively small areas.

To correct this issue we made a custom message that supports partial updates only changing the mesh where needed. To use this custom message you have to build voxblox_rviz_plugin and have it in your workspace when running rviz.

Answer 2

I had this problem too. You just have to source the corresponding setup.bash for the terminal that runs rviz and the /voxblox_node/mesh topic will be available to show in rviz.