What technology lies behind collaborative robots?

[maxobot]

Hi all,

I am aware of some types of motors used in robotics, however I am struggling to find any information on what technology lies behind collaborative robots.
The only version I've got so far is measuring current and adjusting pose to maintain current according to the pose. This would allow human to interact with the robot rather than robot stubbornly maintain set pose and not allow its actuators to be adjusted by simple physical interaction.

Am I overcomplicating this? Maybe there is a simpler solution?

I believe the same technology is employed in exoskeleton.

I am sure there many problems solved in this kind of robots, I am just trying to find where to start learning.

Thanks.

[mklrobo]

  Hello!
I would offer an opinion......  your request;

The only version I've got so far is measuring current and adjusting pose to maintain current according to the pose. This would allow human to interact with the robot rather than robot stubbornly maintain set pose and not allow its actuators to be adjusted by simple physical interaction.
If I am interpreting you correctly, you want the robot to remember what position you told it to maintain, (pose), rather than recording the current of the servo(s) for the movement, correct?
To approach the question, I would look in the robot video section of this forum. They have robots
(I think) close to what you are asking for. This may lead to more options that you are looking for.
In the meantime, I have been pondering over the same question. The only solution that I could come
up with, is to;
Create a movement library that has;
pre-recorded movements associated with certain commands.
catalog these movements into math models, so they can be recombined in new
ways with new or old commands.
A lot of work, to be sure. If you find a better way, please tell me. 

[maxobot]

Thanks mklrobo for your reply!

That's not what I meant. I meant how, say exoskeleton, understands that you want it to lift something? Say, it's holding some weight and you want it to lift it higher by just moving you arm that the exoskeleton is attached to. How would it know that you are putting some effort to lift the weight or lower it?

So it's not about trajectories or movement itself. The question is about sensing that you are moving your arm and helping you to do so. That's what collaborative robots are about, in my understanding.

[mklrobo]

  Hello!
Your reply;
I meant how, say exoskeleton, understands that you want it to lift something? Say, it's holding some weight and you want it to lift it higher by just moving you arm that the exoskeleton is attached to. How would it know that you are putting some effort to lift the weight or lower it?
The question is about sensing that you are moving your arm and helping you to do so. That's what collaborative robots are about, in my understanding.

To further analyze what you are asking; a robotic exoskeleton lifting weight, correct? I have seen
some algorithims on collaborative robots, and, it seems complex how they would integrate separate
AI's into one functioning unit, from that example I saw. But, applications usually are quite different
from the lab ideal.
If I were to invoke imagination, I would look for concept options in movies, such as, Robocop, The 6 Million dollar Man, and/or heros in Comic books.
While this activity is without practical merit, (but fun) it could help in finding options from a certain point of view.
From what I have seen for documentaries, the nerve ending of an amputee is routed to a computer to interpret the motor to be moved. The person has to "re-train" their mind to accommodate the
"bionic" appendage. I assume to have a fully functioning exoskeleton, someone would have to
"jack" into the human brain, and demultiplex the motor commands to the muscles, then activate
the intended muscles for work. Interesting Question....

[maxobot]

Thanks knlrobo for elaborating on this!

By exoskeleton I mean a robotic skeleton that a completely healthy person can wear as a means assisting in carrying heavy objects - an example is a soldier carrying all the ammunition and other stuff (can get to around 40 kg overall at times). So we are not yet on the same page on this.

The ones you are referring to are not yet that mature to perfectly interpret person's intended moves to execute, while I am referring to the ones perfectly and timely executing all required operations and ready for mass production.
This is the kind I am talking about https://www.youtube.com/watch?v=0hkCcoenLW4

I guess FSR (force sensitive resistors can be utilized for an exoskeleton.
But how this beast would let move itself https://www.youtube.com/watch?v=1KevQchHS4w
There are no FSRs there, that's for sure, and that's what I am trying to find out.

[maxobot]

The answer is Force Torque Sensor.

Here is an example: http://robotiq.com/products/robotics-force-torque-sensor/

Those are pretty expensive, unfortunately.

[artbyrobot1]

All you need is to install a "pressure sensor" into the exoskeleton that senses when the arm or leg is trying to move forward and how hard it is pressing against the exoskeleton and the exoskeleton will then be coded to move along with that pressure and direction to accommodate that movement and enhance/strengthen it.  This "pressure sensor" is also called a strain gauge

pressure sensors (aka strain gauge) x10 for robot                                  $9.94 USD

As you can see from the excerpt from my recent purchases log, I purchased these for a dollar or so EACH on ebay and that included shipping.  They are CHEAP!