setting up sensor networks

[sherryyu]

Hi,

I have a few questions.

1.Does anyone know if there is a way to set up wireless communications between the robots? For example zigbee network, or anyway to allow robots to exchange information?

2. What are "range and bearing" sensor and "range and bearing" actuator? And what are their differences?

3. How to add grippers on footbots like in swamanoid project?

Sorry if my questions sound too naive but I do appreciate the help!

[sherryyu]

Btw, by saying grippers I meant grippers that can grab on to another robot not just an object, and potentially lift another robot up

[pincy]

Hi sherryyu,

1.Does anyone know if there is a way to set up wireless communications between the robots? For example zigbee network, or anyway to allow robots to exchange information?

The preferred way is through the range-and-bearing communication system.

A classical WiFi communication system would be nice to introduce, but I never got the time to work on it properly. RoboNetSim is a possible option, but it's for ARGoS2. (see http://people.idsia.ch/~gianni/SwarmRob ... _draft.pdf)

If you feel like contributing with a plugin for WiFi, it's pretty easy to do. I would be happy to help you.

2. What are "range and bearing" sensor and "range and bearing" actuator? And what are their differences?

In ARGoS, the sense phase and act phase are executed separately. The range-and-bearing sensor is that part of the device that receives the data; the actuator is that part that sends the data. For two-way communication (i.e., sending and receiving), you need to use both. Refer to the foraging example (http://www.argos-sim.info/examples.php) to see how to use them.

3. How to add grippers on footbots like in swamanoid project?

The foot-bot gripper is fully simulated. Refer to the gripping example (http://www.argos-sim.info/examples.php). I am working on an enhanced version of this example in these days.

Cheers,
Carlo

[sherryyu]

Hi, Carlo,

Thank you for your reply!

If you feel like contributing with a plugin for WiFi, it's pretty easy to do. I would be happy to help you.

I think range and bearing should be enough for me right now, but I'll be more than happy to try implementing WiFi though. My phd confirmation is in Sept, I will give it a try after that.

The range-and-bearing sensor is that part of the device that receives the data; the actuator is that part that sends the data.

I'm not quite sure how I should see this in reality...like a ZigBee module? If so, what's range-and-bearing's communication range?

The foot-bot gripper is fully simulated. Refer to the gripping example (http://www.argos-sim.info/examples.php). I am working on an enhanced version of this example in these days.

I have added the gripper and was trying to drag a footbot with another footbot, but couldn't move it.

What I did was setting one footbot

Code: Select all

m_pcWheels->SetLinearVelocity(0.0f, 0.0f);

, then let another footbot approach it,

Code: Select all

m_pcGripper->LockPositive()

, then move back. However the two footbots just stuck together and didn't move.

Do you have any idea why? And is it possible for one footbot to lift another one up?

I really appreciate the help!

[pincy]

If you feel like contributing with a plugin for WiFi, it's pretty easy to do. I would be happy to help you.

I think range and bearing should be enough for me right now, but I'll be more than happy to try implementing WiFi though. My phd confirmation is in Sept, I will give it a try after that.

OK, awesome!

The range-and-bearing sensor is that part of the device that receives the data; the actuator is that part that sends the data.

I'm not quite sure how I should see this in reality...like a ZigBee module? If so, what's range-and-bearing's communication range?

The range and bearing communication range is 6 meters on the foot-bot and the eye-bot, and 80cm on the e-puck -- although it's actually a parameter you can set in the experiment configuration file. Have a look at the output of argos3 -q foot-bot.

The foot-bot gripper is fully simulated. Refer to the gripping example (http://www.argos-sim.info/examples.php). I am working on an enhanced version of this example in these days.

I have added the gripper and was trying to drag a footbot with another footbot, but couldn't move it.
What I did was setting one footbot

Code: Select all

m_pcWheels->SetLinearVelocity(0.0f, 0.0f);

, then let another footbot approach it,

Code: Select all

m_pcGripper->LockPositive()

, then move back. However the two footbots just stuck together and didn't move.
Do you have any idea why? And is it possible for one footbot to lift another one up?

I never actually tested this It's probably just due to the fact that the foot-bot is too heavy to be moved away. In real life this is rather accurate. If you need to drag robots around, I can come up with a solution (e.g., add a parameter to make a robot `draggable', or make the robot stronger when it drags stuff around).

Do you actually need to have robots dragged around? What are you trying to achieve?

Cheers,
Carlo

[sherryyu]

Hi, Carlo,

Thank you so much for your reply!

The range and bearing communication range is 6 meters on the foot-bot and the eye-bot, and 80cm on the e-puck -- although it's actually a parameter you can set in the experiment configuration file. Have a look at the output of argos3 -q foot-bot.

Got it, thanks!

I never actually tested this It's probably just due to the fact that the foot-bot is too heavy to be moved away. In real life this is rather accurate. If you need to drag robots around, I can come up with a solution (e.g., add a parameter to make a robot `draggable', or make the robot stronger when it drags stuff around).

I've did some more tests on this. I think the mass is the issue. I was able to drag the cylinder in the examples with footbot speed set to (-5,-5) and (0,0) alternatively. (Sorry this is a really bad controller, but I've fixed this bug) This doesn't work with dragging another footbot though. The other footbot got dragged for a short distance and stopped. Then I set the "mover" footbot to constant speed, it was able to drag another footbot around. So I guess it's fine now

Do you actually need to have robots dragged around? What are you trying to achieve?

I'm doing an self-assembly project. Kinda like the Symbrion project. Ideally I should simulate 3D experiments where robots can connect and move together.

[pincy]

[...] I set the "mover" footbot to constant speed, it was able to drag another footbot around. So I guess it's fine now

Great! Happy to hear that

Do you actually need to have robots dragged around? What are you trying to achieve?

I'm doing an self-assembly project. Kinda like the Symbrion project. Ideally I should simulate 3D experiments where robots can connect and move together.

That sounds like a nice idea. Keep me posted, I'd be curious to see what you achieve

[sherryyu]

That sounds like a nice idea. Keep me posted, I'd be curious to see what you achieve

Will certainly do! I'm Dr. Jan Carlo Barca's student btw