HI! im using this package https://github.com/ros-planning/moveit_grasps for grasp generator , but i had the below error , i cant foud a solution , for this error , im triyng to replicate the graspposevisualizer_demo.cpp with my own configuration , but it dosent works , has anyone can help me please

Im using kinetic ROS version.

process[joint_state_publisher-1]: started with pid [9916]
process[joint_state_desired_publisher-2]: started with pid [9917]
process[robot_state_publisher-3]: started with pid [9918]
process[moveit_grasps_demo-4]: started with pid [9925]
[ INFO] [1582151430.341388679]: Grasp Poses Visualizer
[ INFO] [1582151430.351252575]: End Effector: gripper
[ INFO] [1582151430.351296709]: Planning Group: arm
[ INFO] [1582151430.947705762]: No planning scene passed into moveit_visual_tools, creating one.
[ INFO] [1582151430.960129608]: Loading robot model 'brazo'...
[ INFO] [1582151430.960245690]: No root/virtual joint specified in SRDF. Assuming fixed joint
[ WARN] [1582151431.293907899]: Could not identify parent group for end-effector 'gripper_eef'
[ INFO] [1582151432.449661323]: Publishing maintained planning scene on ''
[ WARN] [1582151433.450576079]: Joint 'virtual_joint' does not exist.
[ WARN] [1582151433.450800916]: Unable to apply virtual joint transform, hideRobot() functionality is disabled
[ERROR] [1582151433.505550943]: Group '' not found in model 'brazo'
[ERROR] [1582151433.505593642]: Link '' not found in model 'brazo'
[moveit_grasps_demo-4] process has died [pid 9925, exit code -11, cmd /home/ixmatix-manuel/openDog_arm/devel/lib/moveit_grasps/moveit_grasps_grasp_poses_visualizer_demo __name:=moveit_grasps_demo __log:=/home/ixmatix-manuel/.ros/log/65874568-5367-11ea-b347-9822ef891d27/moveit_grasps_demo-4.log].
log file: /home/ixmatix-manuel/.ros/log/65874568-5367-11ea-b347-9822ef891d27/moveit_grasps_demo-4*.log

The error occurs in this line : graspdata.reset(new GraspData(nh, eegroupname, visualtools->getRobotModel()));