Manipulate Gripper Orientation

Requests regarding how to set up experiments in ARGoS.
randusr
Posts: 4
Joined: Fri Jan 19, 2018 9:21 am

Manipulate Gripper Orientation

Postby randusr » Fri Feb 02, 2018 2:46 pm

Is there a way to get or set the Gripper orientation of a Footbot?
At the beginning of a simulation the Gripper is always at the front, but the gripper moves while carrying an object. This makes a second grip impossible, without knowing the current orientation of the gripper or the possibility to move the gripper to a kown position.

pincy
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Re: Manipulate Gripper Orientation

Postby pincy » Sat Feb 03, 2018 5:54 pm

Yes, use the foot-bot gripper actuator. Use

argos3 -q footbot_gripper

to find out more, and check the header file here:

/usr/include/argos3/plugins/robots/foot-bot/control_interface/ci_footbot_gripper_actuator.h

or here:

/usr/local/include/argos3/plugins/robots/foot-bot/control_interface/ci_footbot_gripper_actuator.h

depending on where argos is installed. Type

which argos3

to know whether it's /usr or /usr/local.
I made ARGoS.

randusr
Posts: 4
Joined: Fri Jan 19, 2018 9:21 am

Re: Manipulate Gripper Orientation

Postby randusr » Mon Feb 05, 2018 4:11 pm

Hi,

the function-definitions in ci_footbot_gripper_actuator.h allow only for manipulating the gripper lock state.

My problem is the following: As soon as the gripper orientation (realtive to the robot) is altered (for example by draging a cylinder) the robot cannot grab another object, because I don't know how to get the current position of the whole gripper.
At the beginning of each simulation, the gripper is aligned with the robots wheels (0°) and thus in a defined state. But if the orientation of the gripper changes by, for example 170° relative to the robot base (so nearly at the back of the robot), I cannot find a function to check or set the grippers orientation.

In the argos-gripping-example this is not a problem, because the robot does not change its orientation relative to the cylinder and thus the gripper is still at the front, when the footbot releases the cylinder.

Could you point out to me how to overcome this problem?

I already tried the CGripperEquippedEntity.GetDirection() function. But it always returns a CVector::X.

pincy
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Re: Manipulate Gripper Orientation

Postby pincy » Mon Feb 05, 2018 8:56 pm

Have you tried the foot-bot turret actuator?
I made ARGoS.

randusr
Posts: 4
Joined: Fri Jan 19, 2018 9:21 am

Re: Manipulate Gripper Orientation

Postby randusr » Tue Feb 06, 2018 11:56 am

Thank you, that did the trick!

I did not come up with the idea to check other plugins.
Maybe it should be mentioned in the 'argos3 -q footbot_gripper' output?

pincy
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Posts: 632
Joined: Thu Mar 08, 2012 8:04 pm
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Re: Manipulate Gripper Orientation

Postby pincy » Tue Feb 06, 2018 11:10 pm

That's a nice suggestion, thanks!
I made ARGoS.


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