I did post about my problem on answers.ros.org several days ago
(http://answers.ros.org/question/38220/unexpected-behavior-when-trying-to-set-position-of/),
but got no response.
Thanks for the tip about the gazebo mailing list though. I will try that out.

Cameron

> Cameron,
>
> You'd probably get more help by posting a question on
> http://answers.ros.org, or asking the gazebo mailing list directly:
>
> https://kforge.ros.org/mailman/listinfo/gazebo-list
>
> -j
>
> On Wed, Jul 18, 2012 at 7:26 AM,  <cameronlee@berkeley.edu> wrote:
>> Hi,
>> I am using gazebo_msgs/SetModelConfiguration.srv to move a PR2 arm
>> through
>> a path in Gazebo. For the past few months, it has worked fine, but
>> recently (within the last week or two), I have run into some unexpected
>> behavior. When I try to set the position of one arm, the PR2 seems to
>> try
>> to go back to an initial state (both arms get reset) before moving to my
>> specified position. Specifying the joint configurations of both arms in
>> a
>> service call seems to solve this problem. In either case, each time I
>> call
>> the service, the PR2 also seems to shift around like it is in collision
>> with something. When I try to move an arm through a path in small steps,
>> the shifting is more prominent, and the robot eventually just falls
>> through the floor. Does anyone have an idea of what could be happening?
>>
>> I am turning off the controllers before making the service call, so that
>> shouldn't be the problem.
>>
>> Here is the code I am using:
>> set_model_config_client =
>> rospy.ServiceProxy("/gazebo/set_model_configuration",
>> SetModelConfiguration)
>> req = SetModelConfigurationRequest()
>> req.model_name = "pr2"
>> req.urdf_param_name = "robot_description"
>> req.joint_names = rospy.get_param("/%s/joints" % ("r_arm_controller"))
>> req.joint_positions = angles
>> rospy.wait_for_service("/gazebo/set_model_configuration")
>> res = set_model_config_client(req)
>>
>> *angles is the list of joint angles specifying the position of the right
>> arm
>>
>> Thank you,
>> Cameron
>>
>>
>> _______________________________________________
>> ros-users mailing list
>> ros-users@code.ros.org
>> https://code.ros.org/mailman/listinfo/ros-users
>
>
>
> --
> Jonathan Bohren
> PhD Student
> Dynamical Systems and Control Laboratory
> Laboratory for Computational Sensing and Robotics
> The Johns Hopkins University
>
> (707) 520-4736
> jbo@jhu.edu
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