ssm_safety

The package has two modules that provide an optimized speed and separation monitoring package to slow down the robot in case of human-robot proximity.

velocity_scaling_iso15066

The module needs the information on the target trajectory, and the actual robot position. Then, the position is projected on the trajectory, and using the information on the human position with respect to the robot, the scaling override is computed.

The module subscribes:

• a message of the type sensor_msgs::JointState with the unscaled joint target.

• a message of the type geometry_msgs::PoseArray containing the poses of human body parts (i.e. a human) in the scene reference frame.

The module publishes:

• a message of the type std_msgs::Int64 containing the safety override 0-100 (the topics are two, with the same content, to have a redundant communication channel)

fixed_areas_ssm

The module needs the position of the human in the cell. The robot slows down if the human enters in predefined zones. The module subscribes:

• a message of the type geometry_msgs::PoseArray containing the poses of human body parts (i.e. a human) in the scene reference frame.

The module publishes:

• a message of the type std_msgs::Int64 containing the safety override 0-100 (the topics are two, with the same content, to have a redundant communication channel)

References

The concept behind the implementation of package velocity_scaling_iso15066 was described in Sec. III-F of the following paper:

@article{faroni2022safety,
  title={Safety-aware time-optimal motion planning with uncertain human state estimation},
  author={Faroni, Marco and Beschi, Manuel and Pedrocchi, Nicola},
  journal={IEEE Robotics and Automation Letters},
  volume={7},
  number={4},
  pages={12219--12226},
  year={2022},
  publisher={IEEE}
}