I get an error when launching the razer hydra publisher. I am using indigo-devel branch. Here is the output from roslaunch razer_hydra hydra.launch:

Checking log directory for disk usage. This may take awhile.
Press Ctrl-C to interrupt
Done checking log file disk usage. Usage is <1GB.

started roslaunch server http://192.168.100.81:39343/

SUMMARY
========

PARAMETERS
 * /razer_hydra_driver/corner_hz: 3.0
 * /razer_hydra_driver/device: /dev/hydra
 * /razer_hydra_driver/grab_x: 0.12
 * /razer_hydra_driver/grab_y: 0.0
 * /razer_hydra_driver/grab_z: 0.0
 * /razer_hydra_driver/pivot_x: 0.04
 * /razer_hydra_driver/pivot_y: 0.0
 * /razer_hydra_driver/pivot_z: 0.0
 * /razer_hydra_driver/polling_ms: 10
 * /razer_hydra_driver/publish_tf: False
 * /razer_hydra_driver/use_grab_frame: True
 * /rosdistro: indigo
 * /rosversion: 1.11.8

NODES
  /
    razer_hydra_driver (razer_hydra/hydra_node)

ROS_MASTER_URI=http://localhost:11311

core service [/rosout] found
process[razer_hydra_driver-1]: started with pid [12502]
[ INFO] [1408542580.469668184]: Using filter corner frequency of 3.0 Hz
[ INFO] [1408542580.474835312]: Setting pivot offset [0.040, 0.000, 0.000]
[ INFO] [1408542580.474863200]: Setting grab offset [0.120, 0.000, 0.000]
[ INFO] [1408542580.474879655]: Sending messages using the 'grab' frame.
[ INFO] [1408542580.476446018]: opening hydra on /dev/hydra
[ERROR] [1408542580.476481953]: couldn't open hidraw device
[FATAL] [1408542580.476504570]: couldn't open hydra on /dev/hydra
[razer_hydra_driver-1] process has died [pid 12502, exit code 1, cmd /home/haidu/sandbox/catkin_workspace/devel/lib/razer_hydra/hydra_node __name:=razer_hydra_driver __log:=/home/haidu/.ros/log/fb8cb616-286a-11e4-b7fa-e03f4979f6f0/razer_hydra_driver-1.log].
log file: /home/haidu/.ros/log/fb8cb616-286a-11e4-b7fa-e03f4979f6f0/razer_hydra_driver-1*.log
all processes on machine have died, roslaunch will exit
shutting down processing monitor...
... shutting down processing monitor complete
done