Description

This package allows ROS interface with the Novint Falcon Device.

1. Authors

Steven Martin:

Adnan Munawar: amunawar@wpi.edu

2. Dependencies

Tested on ROS Hydro, Indigo and Melodic. For this package to work, please download, build and install the libnifalcon drivers from:

https://github.com/libnifalcon/libnifalcon

3. Setting the permissions

Setting the udev permissions is required. The following commands can be used for this purpose:

roscd ros_falcon
sudo cp udev_rules/99-udev-novint.rules /etc/udev/rules.d

Then unplug and replug the device. You may also need to restart the OS.

4. How to Run:

Before running this ROS program, you may need to run the utility binaries from the libnifalcon package. If you installed the libnifalcon package properly (i.e. by running sudo make install), the binaries should be in your system include path. Otherwise, they should be in <libnifalcon/build/bin> folder.

Make sure that the power cord in plugged into the Falcon and the Falcon is connected to the PC. Run the following in your terminal

findfalcons

You should see the Falcon's LEDs change color and the terminal should indicated whether the Falcon is ready or not. If the program fails, running it a few times helps. You may need to run the program with sudo if the udev permissions were not set properly. However, you would need the udev set correctly for the ROS pacakge to work.

IMPORTANT: YOU MAY ALSO NEED TO HOME THE FALCON WHILE THE PROGRAM IS RUNNING. READ SECTION 4.1 ON HOW TO DO THAT

Now you can run another utility program to test an example where a virtual spherical collider is placed at the center of the Falcon's workspace.

barrow_mechanics

4.1 Homing the Falcon:

The Falcon is homed by running any utility program that accesses the Falcon, then pulling the knob all the way outwards and then pushing it inwards until you sense a locking force. At this point, the falcon is homed.

If these steps work, then you should be able to use the ROS pacakge.

4.2. Running the ROS package:

rosrun ros_falcon driver

This program should spawn the required ROS topics for state/command of the Falcon device.

5. Known Issues:

5.1 Moving the Falcon does not change the state data

You may need to home the Falcon as described in 4.1

5.2 Library not found

For the following error, Error while loading shared libraries: libnifalcon.so.1.0.2: cannot open shared object file: No such file or directory

Try running sudo ldconfig