added a fake laserscanner

[hsd-dev]

Related to #52

By default publishes the laser scan from /scan topic as it is:

roslaunch metacontrol_sim fake_laserscanner_bringup.launch

The data can be "corrupted" by adding a transformation function:

roslaunch metacontrol_sim fake_laserscanner_bringup.launch range_transformer:='[0 for x in m.ranges]'

[hsd-dev]

@chcorbato

[hsd-dev]

One disadvantage I see with this method is that the scans cannot be changed to corrupted at runtime.

[marioney]

One disadvantage I see with this method is that the scans cannot be changed to corrupted at runtime.

This can be problematic. isn't it possible to add a service to change this?

[hsd-dev]

isn't it possible to add a service to change this?

Working on it. Will add another commit.

[hsd-dev]

Original code from here. Unfortunately, it not a python module. So copy-pasted with due credits

metacontrol_sim/scripts/fake_laserscanner.py

Lines 18 to 24 in 392eced

	"""
	@author: enriquefernandez
	Original file: https://github.com/ros/ros_comm/blob/noetic-devel/tools/topic_tools/scripts/transform
	CHANGES:
	- added Lock to original TopicOp class
	- added a service to change transform function at run-time
	"""

The inherited class now exposes a service which can be used to "corrupt" the data:

rosservice call /transform_range "data: true"

The transformation function can be set as an arg in the launch file:

metacontrol_sim/launch/fake_laserscanner_bringup.launch

Line 4 in 392eced

<arg name="transform_fn" default="[0 for x in m.ranges]" />

Currently the range values are simply set to 0s.

[chcorbato]

@marioney can you review this?