ZED Integration with Robot

Software ROS1
1

Hello,
I am trying to integrate the ZED camera with a Clearpath Husky that’s using ROS1. I am trying to use RTABMAP to used LIDAR + Camera for SLAM. I started by trying to add the ZED URDF to the Husky URDF, but I am running into issues.

2

Hi @sesem738
Welcome to the Stereolabs community.

Please provide more information concerning the problems that you are facing.

3

I changed the URDF of the Husky, by following the tutorial for the ZED robot integration for ROS 2, but modifying it for ROS1. I am not receiving any errors outright, but I cannot see any links or joints when I run rviz. This only started to happen when I added the ZED to the URDF so I am definitely doing something wrong.
I have attached pictures showing how I added the ZED to the URDF

zed
zed879×236 37.7 KB

4

ROS and ROS 2 have different behaviors.
You cannot use the guide for ROS 2 in ROS.

5

How do I go about it with ROS1?

6

The file zed_descr.urdf.xacro is only an example of how to include the ZED macro in a robot.
You can simply copy and paste this part

  <xacro:include filename="$(find zed_wrapper)/urdf/zed_macro.urdf.xacro" />
  <xacro:zed_camera name="$(arg camera_name)" model="$(arg camera_model)" parent="$(arg base_frame)">
    <origin 
      xyz="$(arg cam_pos_x) $(arg cam_pos_y) $(arg cam_pos_z)" 
      rpy="$(arg cam_roll) $(arg cam_pitch) $(arg cam_yaw)"
    />
  </xacro:zed_camera>

in the URDF of your robot, after setting the correct value for each parameter:

  • base_frame
  • camera_name
  • camera_model
  • cam_pos_x, cam_pos_y, cam_pos_z
  • cam_roll, cam_pitch, cam_yaw
7

Hi,
I was able to add the ZED to the robot’s URDF following your instructions. However, now when I launch the roslaunch zed_wrapper zed2i, the transforms get all messed up. I edited the launch file to set publish_tf to false, but the transforms still get messed up. Please, how do I go about this?

8

Please publish your TF tree to understand more concerning the “messed” status.

9

This is the TF tree before I run the ZED Wrapper launch file

frames
frames7038×1702 617 KB

10

This is the TF tree after I run the launch file. I do get an error says Failed to get static transforms. Is the ROBOT STATE PUBLISHER node correctly working

frames_after_zed_nodes
frames_after_zed_nodes7897×1850 1010 KB

11

You changed something in the ZED URDF file that broke the tree.
Please check it against the online version

12

Hi, you were right. I made the mistake of making the name in the zed2i launch file zed2i instead of zed. Anyways, I am going to write down what I did so that people can use it as a reference should they run into the same issues.

I am using the Clearpath Husky Robot which has “base_link” as its base link. However, I have my camera mounted with respect to the “user_rail_link” so that’s what I declared as my base_link.

  1. I copy pasted sample from the zed_descr.urdf.xacro in another file and included it in my URDF of the Husky. The camera name="zed", the model="zed2i", parent="user_rail_link" and the camera position with respect to the user_rail_link

  2. I edit the zed2i launch file in the zed_wrapper. I change `publish_urdf=false’ and the camera position w.r.t user_rail_link

  3. I edit common.yaml in params. I change base_frame: user_rail_link and publish_tf=false

13

Anytime, I turn set “publish_tf=true”, it attaches odom directly to user_rail_link instead of odom -> base_link -> user_rail_link how do I add that transform?

14

You must change it here and in the URDF