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2019-07-24 16:21:55 -0600 received badge  Famous Question (source)
2019-04-23 12:50:37 -0600 commented question Prevent Model from flexing

Can you please post your URDF file? Need to be able to see that as well. I suspect the problem may be in your URDF file.

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2019-04-10 17:22:35 -0600 commented answer 4 Wheel Robot wheels unstable. Fix needed.

@josephcoombe I found another way around it. I found that if you put a "pre" tag before and a "/pre" tag after the code,

2019-04-10 16:50:18 -0600 received badge  Notable Question (source)
2019-04-09 23:16:39 -0600 commented question Simple open/close operation (ROS)

I'm guessing the reason no one has attempted to answer this is because it is VERY vague. You may need to reconstruct you

2019-04-09 23:16:13 -0600 answered a question Simple open/close operation (ROS)

I'm guessing the reason no one has attempted to answer this is because it is VERY vague. You may need to reconstruct you

2019-04-09 10:31:37 -0600 received badge  Popular Question (source)
2019-04-09 06:32:54 -0600 answered a question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

So I found out you can stop gazebo from broadcasting the odom -> Base_footprint transform by going to the launch file

2019-04-09 03:17:05 -0600 commented question custom 3d mesh does not show in Gazebo

Hi, @Ince I sincerely doubt this is an OS problem. I tried seeing your project via the link you posted and it says I nee

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2019-04-05 09:27:03 -0600 answered a question LIDAR model publishes upside-down pointcloud

Maybe you should try creating a different reference link for your lidar sensor. <link name="laser_optical_link"/>

2019-04-05 09:19:43 -0600 commented question custom 3d mesh does not show in Gazebo

Can you post your code here? That way it is easier to attempt to replicate the problem you have. Your SDF file and your

2019-04-05 08:59:24 -0600 answered a question Difference between writing stuff directly into URDF vs. into <gazebo reference=""> tags?

As far as I know... A gazebo reference tag tells your ROS URDF file what properties a link should have in gazebo. It def

2019-04-05 08:54:35 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:53:25 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:51:55 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:48:18 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:47:15 -0600 commented answer 4 Wheel Robot wheels unstable. Fix needed.

Oh wow. I meant '' '' tags. Thanks.

2019-04-05 08:46:35 -0600 commented answer 4 Wheel Robot wheels unstable. Fix needed.

Hi @josephcombe Please can you tell me how you edited my post to neatly box up the code? I'm struggling to get it done.

2019-04-05 08:35:02 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:33:18 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:31:58 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:30:35 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

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2019-04-05 08:28:23 -0600 edited question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-05 08:27:13 -0600 asked a question GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED.

GAZEBO SPAWNING UNWANTED ODOM TO BASE LINK TRANSFORM. FIX NEEDED. Hi all, I built my custom 4wheeler and after spawning

2019-04-02 02:50:08 -0600 commented answer 4 Wheel Robot wheels unstable. Fix needed.

WOW!!! I did not even need to rerun the simulation to know this was correct. The verdict lined up perfectly with what I

2019-04-02 02:48:31 -0600 marked best answer 4 Wheel Robot wheels unstable. Fix needed.

Hi All, I am new here and this is my first question and as a result I can't post images so will do the best I can to explain what I'm experiencing.

Platform Details: Distributor ID: Ubuntu Description: Ubuntu 18.04.2 LTS Release: 18.04 Codename: bionic ROS Distro: Melodic

I successfully spawned a 4 wheeler in Gazebo and for some reason, every half revolution, this Robot's wheels sink into an imaginary hole in Gazebo's plane. Imagine that you have 4 wheels with a small segment cut off (not enough to make their cross section a semi circle but almost), that's exactly how they behave. What happens is after every half revolution, part of the wheels sink below the ground plane in Gazebo and then literally rise back to the surface. Between revolutions everything is fine by the way.

See my robot URDF below. I have seen a similar question in this link but all it stated was the wheels were perpetually below the ground plane. This is not my case. The Robot behaves as it should in between half revolutions. Note that I have experimented with robot weights and Kp values of the wheels (used a stepwise approach to no avail). Please help. I am at my wits' end. Note that the part of the code that is the wheels is refered to <xacro:macro name="wheel_position_macro" params="prefix suffix reflect1 reflect2">

Thanks in anticipation of your help.

<?xml version = "1.0"?>
<robot name="Rover" xmlns:xacro="http://www.ros.org/wiki/xacro">

<xacro:property name="wheel_thickness" value="0.15"/>
<xacro:property name="wheel_diameter" value="0.4"/>
<xacro:property name="wheel_guide_thickness" value="0.05"/>
<xacro:property name="wheel_guide_length" value="0.4"/>
<xacro:property name="wheel_guide_height" value="0.1"/>
<xacro:property name="body_length" value="0.6"/>
<xacro:property name="body_width" value="0.5"/>
<xacro:property name="body_height" value="0.3"/>
<xacro:property name="camera_width" value="0.01"/>
<xacro:property name="wheel_mass" value="0.5"/>
<xacro:property name="body_mass" value="1"/>
<xacro:property name="guide_mass" value="0.5"/>
<xacro:property name="axel_mass" value="0.5"/>
<xacro:property name="camera_mass" value="0.1"/>
<xacro:property name="kinect_mass" value="0.5"/>
<xacro:property name="pi" value="3.1415"/>

<xacro:macro name="default_inertial" params="mass">
  <inertial>
    <mass value="${mass}"/>
    <inertia ixx="1.0" ixy="0.0" ixz="0.0" iyy="1.0" iyz="0.0" izz="1.0"/>
  </inertial>
</xacro:macro>


<xacro:macro name="shape_visual" params="length width height color">
  <visual>
    <pose xyz="0 0 1.0"/>
    <geometry>
      <box size="${length} ${width} ${height}"/>
    </geometry>
    <material name="${color}"/>
  </visual>
  <collision>
    <geometry>
      <box size="${length} ${width} ${height}"/>
    </geometry>    
  </collision>

</xacro:macro>

<xacro:macro name="camera_visual" params="length width height color">
  <visual>
    <geometry>
      <box size="${length} ${width} ${height}"/>
    </geometry>
    <material name="${color}"/>
  </visual>
  <collision>
    <geometry>
      <box size="${length} ${width} ${height}"/>
    </geometry>    
  </collision>

</xacro:macro>

<xacro:macro name="wheel_guide_macro" params="prefix reflect">
<link name="${prefix}_wheel_guide">
  <visual>
    <origin xyz="0 ${reflect*wheel_guide_thickness/2} 0"/>
    <geometry>
      <box size="${wheel_guide_length} ${wheel_guide_thickness} ${wheel_guide_height}"/>
    </geometry>
    <material ...
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2019-04-01 13:19:34 -0600 commented question 4 Wheel Robot wheels unstable. Fix needed.

I'm a newbie on here @josephcoombe I am not allowed to post images and/or videos. However, Imagine that there were potho

2019-04-01 12:15:25 -0600 received badge  Popular Question (source)
2019-03-31 11:12:02 -0600 asked a question 4 Wheel Robot wheels unstable. Fix needed.

4 Wheel Robot wheels unstable. Fix needed. Hi All, I am new here and this is my first question and as a result I can't

2019-03-31 11:12:00 -0600 commented answer My wheeled robot model sometimes flies up into the air while driving. Why?

Some of these links are damaged. This one is. PLease could you point us to the current functional link if you don't mind

2019-03-31 11:11:59 -0600 commented answer Gazebo 1.5: libgazebo_openni_kinect.so: pointcloud data is rotated and flipped?

@M.Otubela Your solution is apt. i used it and it worked like magic. using a different TF for just the sensor nailed it.