Removes two IMU launch files. They are not used by other
stretch_ros code, and they appear to not function properly.
For example, they do not appear to use a proper tf frame for
the IMU, can produce problematic tf trees, and can result
in tf query timing problems.

The demo launch files started IMU nodes that were
unused, produced warnings, and created problematic tf trees.
With this commit, they no longer start these nodes.
Quick tests of some of the demos indicate that they
work as well as they did before. However, I did not test
hello_world.launch.

FUNMAP obstacle detection failed due to the frustum of the
RGB colored 3D points not overlapping with the region in front
of the robot that is required to detect the floor when moving
forward. Since the IR camera 3D point frustum still overlaps
with the region, it seems that an upstream Realsense D435i
change may be causing only the RGB colored 3D points to be used
now.

For now, this is a quick fix that makes the robot look down lower
when moving forward, so that the color camera frustum overlaps
with the obstacle detection region.

The FUNMAP mapping launch file started IMU nodes that were
unused, produced warnings, and created a problematic tf tree.
With this commit, mapping.launch no longer starts these nodes.
Mapping and navigation continued to function in a brief test
and the IMU related warnings were no longer produced.

I used the following command for testing.

$ roslaunch stretch_funmap mapping.launch

I primarily removed commented code.

After these changes, FUNMAP mapping capabilities worked for me
in a small room. I tested the following capabilities:

 + head scans
 + merging head scans
 + navigating to a clicked pose
 + navigating and reaching to a clicked 3D point
 + autonomously navigating to a good place to scan
 + changing pose to a clicked pose
 + estimating nearby pose on a map
 + estimating global pose on a map

I tested these using the following launch command:

$ roslaunch stretch_funmap mapping.launch

I made a variety of changes, including the following:

 + \ => \\ for divisions that appeared to need an integer output
 + changed height bounds for floor segments (-0.05 m to 0.05 m)

Two notable remaining issues follow:

[ WARN] [1622754350.710109968]: Could not obtain transform from imu_mobile_base to base_link. Error was Could not find a connection between 'base_link' and 'imu_mobile_base' because they are not part of the same tree.Tf has two or more unconnected trees.

Transforms and URDF visualization sometimes fail after launching.
It can take multiple attempts for FUNMAP mapping to work. There is
significant nondeterminism when launching with mapping.launch.

NOT FULLY TESTED

After these very minor changes, the following command
appeared to execute properly. However, I didn't bother
attaching the dry-erase marker tool. Instead, I placed
the robot in front of a whiteboard and caught and followed
the gripper with my hand at the surface of the board
to simulate lower-friction dry-erase marker contact.
It successfully aligned itself with the board, stopped on
contact with my hand, and completed all of the writing
motions.

$ roslaunch stretch_demos hello_world.launch

After these very minor changes, surface cleaning with the
following command worked for me. Stretch wiped the top of
a small nightstand.

$ roslaunch stretch_demos clean_surface.launch

Proactive changes based on most recent porting.

+ Removed unused skimage imports

+ / => // where an integer output seemed to be expected

After these changes, object grasping with the following command
worked for me. Stretch grasped a cup from a small nightstand.

$ roslaunch stretch_demos grasp_object.launch

Changes include the following:

+ / => // for some places where an integer output is required

+ changes for scikit_image (import skimage) 0.18.1
  + skimage.measure.label argument change
  + skimage.measure.regionprops argument change

After this minor change, drawer opening worked with the
following command.

$ roslaunch stretch_demos open_drawer.launch

The following persistent warning would be good to resolve.

[ WARN] [1622728896.394958823]: Could not obtain transform from imu_mobile_base to base_link. Error was Could not find a connection between 'base_link' and 'imu_mobile_base' because they are not part of the same tree.Tf has two or more unconnected trees.

With these updates, the handover_object.launch demo succeeded.
The robot successfully moved its hand to me three times in a
row when I moved myself to different positions. The handoff
poses seemed good.

A variety of changes were required to make this work, including
the following:

  + tab vs. spaces cleanup for funmap using "autopep8 -i funmap"

  + updates to cython compilation for Python 3 and recent cython

  + changed import statement pattern to "stretch_funmap.*"

Prior to my successful run of this demo, I encountered an error
related to get_robot_floor_pose_xya in HelloNode in hello_misc.py
(details below). It seems like it may have been a failed transform
lookup by get_p1_to_p2_matrix, which queries TF2 to obtain the
current estimated transformation from the robot's base_link frame
to the frame.

I did not make changes that I would expect to resolve this issue.
I only added a few print statements to hello_misc.py that I
intended to use for debugging. I have left the print statements
in place.

[ERROR] [1622656837.765018]: Error processing request: matmul: Input operand 0 does not have enough dimensions (has 0, gufunc core with signature (n?,k),(k,m?)->(n?,m?) requires 1)
['Traceback (most recent call last):\n', '  File "/opt/ros/noetic/lib/python3/dist-packages/rospy/impl/tcpros_service.py", line 632, in _handle_request\n    response = convert_return_to_response(self.handler(request), self.response_class)\n', '  File "/home/ck/catkin_ws/src/stretch_ros/stretch_demos/nodes/handover_object", line 178, in trigger_handover_object_callback\n    at_goal = self.move_base.forward(self.mobile_base_forward_m, detect_obstacles=False, tolerance_distance_m=tolerance_distance_m)\n', '  File "/home/ck/catkin_ws/src/stretch_ros/stretch_funmap/src/stretch_funmap/navigate.py", line 245, in forward\n    xya, timestamp = self.node.get_robot_floor_pose_xya()\n', '  File "/home/ck/catkin_ws/src/stretch_ros/hello_helpers/src/hello_helpers/hello_misc.py", line 127, in get_robot_floor_pose_xya\n    r0 = np.matmul(robot_to_odom_mat, r0)[:2]\n', 'ValueError: matmul: Input operand 0 does not have enough dimensions (has 0, gufunc core with signature (n?,k),(k,m?)->(n?,m?) requires 1)\n']

I changed the rviz configuration file for
wheel_odometry_test.launch to avoid a
point cloud visualization issue.

The ROS Noetic Respeaker package did not function as expected.
For now, I'm removing this launch file that depends on it.

I tried and failed to use the following version:

$ apt show ros-noetic-respeaker-ros
Package: ros-noetic-respeaker-ros
Version: 2.1.21-2focal.20210424.002454
Priority: optional
Section: misc
Maintainer: Yuki Furuta <furushchev@jsk.imi.i.u-tokyo.ac.jp>
Installed-Size: 153 kB
Depends: flac, ros-noetic-angles, ros-noetic-audio-common-msgs, ros-noetic-dynamic-reconfigure, ros-noetic-geometry-msgs, ros-noetic-std-msgs, ros-noetic-tf
Download-Size: 20.8 kB
APT-Manual-Installed: yes
APT-Sources: http://packages.ros.org/ros/ubuntu focal/main amd64 Packages
Description: The respeaker_ros package

Python 3 was not well supported by ROS Melodic.
stretch_deep_perception required Python 3, which could
cause issues and confusion. To help clarify when code
used Python 3, the filenames had the pattern *_python3.py.

I've changed the filenames to remove this pattern,
since all of the ROS Noetic code will be using Python 3
by default, and ROS Noetic supports Python 3.