coppeliasim_plugin_velodyne

This CoppeliaSim / V-REP plugin that publishes a full revolution of points in PointCloud2 into ROS under the topic /velodyne_points. Instead of serializing the Velodyne data directly with Non-threaded scripts, this plugin uses C++ to greatly increase publication speed.

The points are global (relative to the odom frame). This plugin is meant to be used with sensors like the built-in model velodyne VPL-16.

The reason why the point cloud is published globally is because at every simulation step the points are converted to the origin frame in order to correct the mismatch due to the movement of the vehicle. You can modify the plugin or simply create a node that reads this point cloud and converts it to the base_link (or whatever the velodyne frame is) frame.

Installation

After cloning this repository and compiling with catkin make, the plugin lib needs to be copied into the CoppeliaSim folder:

$ cp ~/catkin_ws/devel/.private/coppeliasim_plugin_velodyne/lib/libv_repExtRosVelodyne.so $COPPELIASIM_ROOT_DIR

CoppeliaSim / VREP sensor configuration

This is a sample configuration for the stock Velodyne VPL16:

if (sim_call_type==sim.syscb_init) then
    local visionSensorHandles={}
    for i=1,4,1 do
        visionSensorHandles[i]=sim.getObjectHandle('velodyneVPL_16_sensor'..i)
    end
    local frequency=5 -- 5 Hz
    local options=2+8 -- bit0 (1)=do not display points, 
                -- bit1 (2)=display only current points,
                -- bit2 (4)=returned data is polar (otherwise Cartesian), 
                -- bit3 (8)=displayed points are emissive
    local pointSize=2
    local coloring_closeAndFarDistance={1,4}
    local displayScaling=0.999 -- so that points do not appear to disappear in objects


	-- added for local frame version
    h_velodyne_sensor = sim.getObjectHandle('velodyneVPL_16')
    local frameId = "lidar"
    local topic = "/velodyne"
	
    _h=simExtVelodyneROS_createVelodyneROSModel(visionSensorHandles,frequency,options,pointSize,coloring_closeAndFarDistance,displayScaling, h_velodyne_sensor, frameId, topic)
end

if (sim_call_type==sim.syscb_sensing) then
    --Boolean, true if data is published (via VelodyneROS plugin)
    local fullRev=simExtVelodyneROS_handleVelodyneROSModel(_h, sim.getSimulationTimeStep()) 
    --local fullRev=simExtVelodyneROS_handleVelodyneROSModel(_h, sim.getSimulationTimeStep()) --use this if the full 360 cloud is needed instead of 4 separated pointclouds
end

if (sim_call_type==sim.syscb_cleanup) then
    simExtVelodyneROS_destroyVelodyneROSModel(_h)
end