CARMA II Alpha Contamination Avoidance Results

Four files consisting of datasets from Alpha contamination avoidance experiments conducted at RAICo1, Cumbria using the CARMA II UGV platform.

The UGV is instructed to follow a path consisting of concentric polygons, with each vertex as a navigation waypoint.  If avoidance behaviours are enabled, the UGV will not traverse over an area where Alpha contamination has been detected via a front mounted sensor.

All files are txt, human readable, tab delimited, derived from larger ROS bag files recorded during the experimental campaign.  All files contain a header row with descriptions of each column.  Timestamps are in Unix Epoch time (as is standard for the Robot Operating System), positions in metres are given with a captial X, Y, Z for each cartesian axis respectively.  The Z value are not necessary for this work, therefore their actual value may not correspond to realworld values, these should be ignored.  Quaternion representations of orientation are given by x, y, z, w.  Finally, any Alpha radiation intensity values are given as counts/sec.  Any position data has been referenced to the first waypoint in the follower path.

Data was originally collected in November 2022 (in ROS bag format), which was interrogated to provide the data in these .txt files.

The position of the Alpha source was located at approximately: X = 2.0 m | Y = -0.4 m

• "AlphaOnly_Travelpath.txt" represents the waypoint positions the UGV should try to match.
• "AlphaOnly_NoAvoidancePath.txt" represents the reference frame of the robot chassis and it's position in space as estimated by SLAM, whilst no avoidance behaviours are enabled.
• "AlphaOnly_WithAvoidancePath.txt" represents the reference frame of the robot chassis and it's position in space as estimated by SLAM, whilst avoidance behaviours are enabled and enacted when Alpha contamination is detected.
• "AlphaOnly_WithAvoidanceAlphaCounts.txt" represents the postion of the radiation detector and the measured counts during the experiment.