Set Gripper Direction towards the front robot

Requests regarding how to set up experiments in ARGoS.
Waqar731
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Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 12:00 pm

Hi Sir,
I am using your code (LUA code for search and rescue) in which a robot is moving towards other robot based on negative and positive angle. Actually there are two functions where in first function the robot detect the location of front robot and get length and angle with that robot. While in second function it set velocity based on previously obtained length and angle. With positive angle it turns towards other robot with following code.

Code: Select all

lvel = length * (1 - 2 * angle / math.pi) rvel = length
And by using above code the gripper becomes set towards front robot where it get easily attach with that robot.

But in case if robot get negative angle with other robot than it moves towards other robot with following code.

Code: Select all

lvel = length rvel = length * (1 + 2 * angle / math.pi)
But with above code the robot moves towards front robot but in this case the gripper is not towards the front robot which is not what i want. In negative angle robots is also moving towards front robot but gripper is not towards front robot side. As shown in attached images where green LED robot is moving towards red LED robot but gripper of green LED robot is opposite to the front RED LED robot.
Screenshot from 2020-03-24 15-54-36.png
Screenshot from 2020-03-24 15-54-36.png (5.79 KiB) Viewed 33071 times
How can we make gripper towards the front robot particularly with negative angle.?

Thanks and Best Regards
Waqar Hussain

pincy
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Re: Set Gripper Direction towards the front robot

Postby pincy » Tue Mar 24, 2020 2:30 pm

Use the turret. Details here: http://argos-sim.info/ascens/
I made ARGoS.

Waqar731
Posts: 65
Joined: Thu Oct 23, 2014 12:33 pm
Location: Pakistan
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Re: Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 3:26 pm

Hi,
Thanks for the reply, I check the link.

Thanks
Waqar Hussain

Waqar731
Posts: 65
Joined: Thu Oct 23, 2014 12:33 pm
Location: Pakistan
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Re: Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 4:53 pm

Yes, I got the idea about rotaing the gripper from the link you mentioned.

But I downloaded the project from that link but there is not a LUA file. Can I get the LUA file?
Waqar Hussain

pincy
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Re: Set Gripper Direction towards the front robot

Postby pincy » Tue Mar 24, 2020 4:55 pm

There is no Lua file. The assignment was to write one from scratch.
I made ARGoS.

Waqar731
Posts: 65
Joined: Thu Oct 23, 2014 12:33 pm
Location: Pakistan
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Re: Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 5:03 pm

I have seen your footbot_gripping example where you put robot 70 steps before the cylinder. After moving 70 steps robots turn on the gripper and attach with it.
Below is the image of your code for footbot_gripper.
Screenshot from 2020-03-24 20-59-46.png
Screenshot from 2020-03-24 20-59-46.png (76.85 KiB) Viewed 33053 times
But in large arena how can we count steps to turn on the gripper to grip the cylinder?


Thanks
Waqar Hussain

pincy
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Re: Set Gripper Direction towards the front robot

Postby pincy » Tue Mar 24, 2020 5:26 pm

You wouldn't count steps in a real robotic setting. You would use sensors. You could place LEDs around the object and use the camera to detect the object.
I made ARGoS.

Waqar731
Posts: 65
Joined: Thu Oct 23, 2014 12:33 pm
Location: Pakistan
Contact:

Re: Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 5:40 pm

Sir I am already using camera for detecting LED, but my question is that at which time should we turn on the gripper actuator?
Currently m using the proximity sensor along with camera sensor. When robot moves towards the object using camera sensor then at the same time robot is getting value from proximity sensor. When robot goes towards near object then on the basis of proximity value it turns on the girpper. I want to confirm it from your side that using proximity is good or not for detecting the nearing of robot?


Thanks
Waqar Hussain

Waqar731
Posts: 65
Joined: Thu Oct 23, 2014 12:33 pm
Location: Pakistan
Contact:

Re: Set Gripper Direction towards the front robot

Postby Waqar731 » Tue Mar 24, 2020 5:45 pm

Is there any value of gripper actuator whose value tell us either the gripper is touching to front side object or not?
Waqar Hussain

pincy
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Re: Set Gripper Direction towards the front robot

Postby pincy » Wed Mar 25, 2020 3:09 am

I am already using camera for detecting LED, but my question is that at which time should we turn on the gripper actuator?
Switch the turret on at the beginning. When your sensors (camera, proximity) tell you that you're close enough, rotate the turret to point at the object. Then approach the object. When the sensors tell you that you're close enough, lock the gripper.
Is there any value of gripper actuator whose value tell us either the gripper is touching to front side object or not?
There is no gripper sensor, no.
I made ARGoS.


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