Scalaser

Overview

The scalaser package was created as a part of the bachelor thesis of Miro Voellmy. It was specifically developed for stair climbing wheelchair Scalevo.

The scalaser package has been tested under ROS Indigo and Ubuntu 14.04. This is research code, expect that it changes often and any fitness for a particular purpose is disclaimed.

The source code is released under a BSD 3-Clause license.

Author: Miro Voellmy
Contact: Miro Voellmy, mvoellmy@ethz.ch
Affiliation: Autonomous Systems Lab, ETH Zurich

Publications

If you use this work in an academic context, please cite the following publication(s):

M. Voellmy, P. Fankhauser, M. Hutter, and R. Siegwart: Stairrecognition on a stair climbing wheelchair using LIDAR Sensors. IEEE/RSJ International Conference of Placeholders (IROS), 2015. (PDF)

Installation

Dependencies

Robot Operating System (ROS) (middleware for robotics),
Eigen (linear algebra library),
Matlab (matlab),
c_matlabcppinterface (matlab C++ interface),
scalevo_msgs (messages package of scalevo),
scalebot (robot model of the scalevo wheelchair)

Building

In order to install, clone the latest version from this repository into your catkin workspace and compile the package using

cd catkin_workspace/src
git clone https://github.com/scalevo/scalaser.git
cd ../
catkin_make

Tests

Package tests have not been implemented yet. You can run this command however to watch Starwars Episode IV in the terminal:

telnet towel.blinkenlights.nl

Usage

First start the two SICK sensors on board of the Scalevo wheelchair using

roslaunch scalaser pointcloud_2.launch

then start the stair recognition node with

roslaunch scalaser angle.launch

Check the launch files if you want to change a modifiable parameters.

Nodes

Angle

Main node to determine the angle of the stair on stairs.

Subscribed Topics

cloud_1 ([sensor_msgs/PointCloud])

Pointcloud of the right laser sensor.
cloud_2 ([sensor_msgs/PointCloud])

Pointcloud of the left laser sensor.

Published Topics

beta ([std_msgs/Float64])

Angle of the wheelchair on the stairs.
stair_parameters ([std_msgs/Float64MultiArray])

Determined parameters of the stair and the wheelchairs position on the stair.
stair_model (visualization_msgs/Marker)

The marker for the stair visualization in rviz.
chair_model (visualization_msgs/Marker)

The marker for the chair visualization in rviz.

Services

trigger (std_srvs/Empty)

Trigger the computation process. For example, you can trigger the computation from the console with
```
  rosservice call /NODE_A_NAME/trigger
```

Parameters

scalaser/fov_s (int, default: 200)

The start of the field of view.
scalaser/fov_s (int, default: 150)

The size of the field of view.
scalaser/kp (double, default: 0.008)

P value used to determine the motor velocity.

StairModel

Publishes a model of the stairs for visualization in rviz.

ChairModel

Publishes a model of the wheelchair positioned on the stairs for visualization in rviz.

Bugs & Feature Requests

Please report bugs and request features using the issue feature of this package.

Scalevo/scalaser