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2022-02-14 16:06:29 -0500 asked a question How are Goals Used in Move_Base?

How are Goals Used in Move_Base? I'm trying to get a better understanding of how Move_Base uses goals it receives from /

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2021-03-07 22:54:42 -0500 marked best answer What Range of Costs Does ROS Navigation Support?

I'm looking to make custom costmap2d layer, where each cell in the occupancy grid would be a range of values rather than a binary OBSTACLE/NO OBSTACLE. For instance, if the robot was trapped between cells with cost 20, and cells with cost 50, it would opt to travel over the lower cost area (20 in this case).

While I know that the occupancy grid can technically take a range of values from [0,100], the costmap2d page on ROS wiki seems to indicate what I want to do is not possible: http://wiki.ros.org/costmap_2d/

Occupied, Free, and Unknown Space While each cell in the costmap can have one of 255 different cost values (see the inflation section), the underlying structure that it uses is capable of representing only three. Specifically, each cell in this structure can be either free, occupied, or unknown. Each status has a special cost value assigned to it upon projection into the costmap. Columns that have a certain number of occupied cells (see mark_threshold parameter) are assigned a costmap_2d::LETHAL_OBSTACLE cost, columns that have a certain number of unknown cells (see unknown_threshold parameter) are assigned a costmap_2d::NO_INFORMATION cost, and other columns are assigned a costmap_2d::FREE_SPACE cost.

Based on my reading of that, the costmap points essentially only has three states it can be in (Occupied, Free, or Unknown), and I can't assign an actual cost to bias the robot to go certain directions.

Is my reading of "only three states" correct? The original layered costmap paper from David Lu (http://wustl.probablydavid.com/public...) seems to indicate that there is a concept of adding non-lethal costs, and variable costs overall, but the wiki entry seems to contradict that.

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2021-01-25 07:58:13 -0500 marked best answer navsat_transform_node to find pose coordinates for a given GPS lat/long

I'm working on a robotic convoy setup entirely in simulation, and want to do the following:

Vehicle 1 - Send its GPS coordinates to follower vehicle (called Vehicle 2)

Vehicle 2- Take the GPS coordinates, convert them to pose coordinates in Vehicle 2's global frame (X,Y coordinates, in case I'm using the wrong words here...), and then use that as a waypoint.

Looking into navsat_transform_node, it seemed like the appropriate tool to do this, but cannot get it to work in a way that makes sense. Here are the things I've tried to do:

1.) Send Vehicle 1's IMU and GPS data to Vehicle 2's navsat_transform_node. When I do this, Veh2's navsat_transform_node ends up publishing pose coordinates in Vehicle 1's global frame. Basically, it just spits out Vehicle 1's odometry/filtered data from Vehicle's 1 perspective.

2.) Send Vehicle 1's GPS data to Vehicle 2's navsat_transform_node, while using Vehicle 2's IMU information. When I do this...the results don't seem to make much sense. The GPS coordinates and how they're transformed into Vehicle 2's global pose coordinate frame don't seem to correspond to cause and effect of what's seen in RVIZ/Gazebo, so I'm assuming this is way off base.

As my assumption of what navsat_transform_node does incorrect, or am I not setting it up correctly?

Some additional notes in case it helps, I'm using Clearpath Husky simulation and robot_localization.

2021-01-24 21:22:35 -0500 commented question navsat_transform_node to find pose coordinates for a given GPS lat/long

Also, didn't realize there was a distinction between Comments and Answers. Just tried to mark this as the answer and was

2021-01-24 21:18:50 -0500 commented question navsat_transform_node to find pose coordinates for a given GPS lat/long

I had some funky thinks going on due to vehicle rotation, but after changing the default alignment of the vehicles so th

2021-01-19 08:25:30 -0500 commented answer launch file doesn't use the parameters

When you run only the node, there are no parameters that are being loaded. In the output for example one, notice that t

2021-01-19 08:25:12 -0500 commented answer launch file doesn't use the parameters

When you run only the node, there are no parameters that are being loaded. In the output for example one, notice that t

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2021-01-18 23:16:21 -0500 answered a question launch file doesn't use the parameters

http://wiki.ros.org/roslaunch/XML/param "You can also set private parameter across a group of nodes by using the ~param

2021-01-18 23:09:14 -0500 commented question navsat_transform_node to find pose coordinates for a given GPS lat/long

Hello! Thanks for the suggestion! Based on what you said, the way I was filling in the IMU data and updating it constan

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2021-01-18 09:18:32 -0500 edited question navsat_transform_node to find pose coordinates for a given GPS lat/long

navsat_transform_node to find pose coordinates for a given GPS lat/long I'm working on a robotic convoy setup entirely i

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2021-01-09 16:42:35 -0500 edited question navsat_transform_node to find pose coordinates for a given GPS lat/long

navsat_transform_node to find pose coordinates for a given GPS lat/long I'm working on a robotic convoy setup entirely i

2021-01-09 16:41:52 -0500 edited question navsat_transform_node to find pose coordinates for a given GPS lat/long

navsat_transform_node to find pose coordinates for a given GPS lat/long I'm working on a robotic convoy setup entirely i

2021-01-09 16:41:50 -0500 edited question navsat_transform_node to find pose coordinates for a given GPS lat/long

navsat_transform_node to find pose coordinates for a given GPS lat/long I'm working on a robotic convoy setup entirely i

2021-01-09 16:05:50 -0500 asked a question navsat_transform_node to find pose coordinates for a given GPS lat/long

navsat_transform_node to find pose coordinates for a given GPS lat/long I'm working on a robotic convoy setup entirely i

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2020-12-31 11:51:26 -0500 commented answer Where is the topic "imu/data" defined?

Yup. frameID is wrong, frameId is right.

2020-12-31 11:50:46 -0500 marked best answer Where is the topic "imu/data" defined?

I am running the Clearpath Husky ROS simulation (https://github.com/husky/husky) and need to change the header frame ID of the topic "imu/data" from "base_link" to add a transform prefix (overall, want it to be "husky_alpha/base_link), so that I can use navsat_transform from robot_localization. I've dug quite extensively in the launch, config, and source files, but can't find any place where I modify or alter that particular topic at all. Any advise on where to go in order to modify "imu/data" so that the header frame_id is different than the default of "base_link"?

Thanks!

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2020-12-30 16:40:32 -0500 commented answer Where is the topic "imu/data" defined?

You found my error! I did indeed try it before, but my mistake was using the tag frameID instead of frameId. Thanks for

2020-12-30 16:40:08 -0500 commented answer Where is the topic "imu/data" defined?

Do you want to pull that previous comment out as its own "Answer" post so I can mark it as "correct"? If you don't care

2020-12-30 16:38:14 -0500 commented answer Where is the topic "imu/data" defined?

You found my error! I did indeed try it before, but my mistake was using the tag <frameid> instead of <frameid&

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2020-12-30 13:27:53 -0500 commented answer Where is the topic "imu/data" defined?

Sure! The frames PDF is a beast, because I'm running three robots at the same time. Here it is: https://drive.google.com

2020-12-29 13:27:32 -0500 commented answer Where is the topic "imu/data" defined?

And for greater clarity, I want to change it because of the following line in navsat_transform: bool can_transform = Ro

2020-12-29 13:27:16 -0500 commented answer Where is the topic "imu/data" defined?

And for greater clarity, I want to change it because of the following line in navsat_transform: bool can_transform = Ro

2020-12-29 13:25:00 -0500 commented answer Where is the topic "imu/data" defined?

Thanks for the suggestion, but that didn't change it. Going to walk through how I'm testing this to sanity check... Fir

2020-12-29 02:21:52 -0500 asked a question Where is the topic "imu/data" defined?

Where is the topic "imu/data" defined? I am running the Clearpath Husky ROS simulation (https://github.com/husky/husky)

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2020-03-17 07:23:10 -0500 commented answer transformPose Not Working in Multiple Robot Setup

Needed to make changes to control.yaml https://answers.ros.org/answers/228931/revisions/

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2020-03-16 22:52:51 -0500 answered a question transformPose Not Working in Multiple Robot Setup

Found my answer here: https://answers.ros.org/question/228380/gazebo-with-multiple-odometery-frames/

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2020-03-15 18:25:13 -0500 asked a question transformPose Not Working in Multiple Robot Setup

transformPose Not Working in Multiple Robot Setup I am working on getting multiple Husky robots running in Gazebo and RV