Mechanics and Construction > Mechanics and Construction

Robot Arm

(1/3) > >>

Tarek:
Hello everybody,
I'm newcomer to this great forum! I'm just another person who is interested in Robotics and would like to get started as soon as possible. I'd like to make a robot arm.
How could I get started? Please tell me everything from the very beginning and give me the suitable links that will help me to learn more about making robotic arm.
I'm planning to buy a book for this purpose. Which book would be better? Please do reply.
I look forward to hearing from you all

Admin:
Actually, a few others have asked the same question too . . .

here are the posts:

http://www.societyofrobots.com/robotforum/index.php?topic=34.0

http://www.societyofrobots.com/robotforum/index.php?topic=68.0

hope that helps!

Tarek:
Hey Admin,
Thanks for reply as well as the links. The links are great!
Actually, I'm gonna make a robot arm that will be used in arc welding purpose - a robotic arm that will hold the manual welding torch and manipulate it according to program. I'm mechanical engineering student and I'm gonna do this as my undergraduate project.
Will it be very tough project? How can I make this project easier? What should be the lengths of the links for this purpose? How strong servo will I need for this?
Thanks

Admin:
Hmmm its doable. There are a lot of books out there for robotic welding.
The affordable automation book on this page has a lot on industrial robotics:
http://www.societyofrobots.com/robottheory.shtml

Key points I remember from them:

* Welding requires very strong arms (to carry the welding device, and hold a high precision position)
* Bright light blinds any cameras, making sensors useless
* The robot arm end effector needs to be highly resistant to heat
* People have been killed by industrial robots, safety is key
Instead of welding, how about brazing instead?
http://www.societyofrobots.com/mechanics_brazing.shtml

I think that brazing instead of welding will simplify your project greatly without sacrifice in quality. It will allow you to shrink your robot to a much smaller, much easier to build, much cheaper device.

As for your other questions:
Shorter link lengths are better in that they

* bend less, allowing higher accuracy and less 'flopping around'
* require less torque to move, and hence smaller/cheaper motorsShorter link lengths are worse in that they

* have a shorter reach
* can only work with smaller parts
To calculate the torque your servos need:
http://www.societyofrobots.com/mechanics_statics.shtml
If you weld and not braze, you will need motors much stronger than servos.

Tarek:
thanks for wonderful suggestion! splendid....i must say!!
I realize brazing instead of welding will be easier to build. But the problem is my supervisor is restricted to welding as he thinks the use of robot for welding purpose is more common and has significant positive impact in Industries. However, I keep trying to convince him to make it brazing instead of welding.

What if I consider Lynx 5 robotic arm for welding? I think it has strong arm and stout gripper for precision. But I don't know about sensors-whether the sensors become useless during welding due to bright light or not.
What do you think? Will it match with that one which I attempt to make for welding? Please check it out:
http://www.active-robots.com/products/robots/lynx5-details.shtml

Lynx 5 Robotic Arm Specs
No of axis = 4 + Gripper
Servo motion control = local closed loop
Height (arm parked) = 5.5"
Height (reaching up) = 14.5"
Reach (forward) = 11"
Gripper opening = 2"
Lift weight (arm extended) = approx. 3 oz
Weight (without batteries) = 18 oz
Range of motion per axis = 180 degrees
Accuracy of motion per axis = Servo controller dependant (SSC32=.09 degrees)
Servo voltage = 6 vdc

Any additional suggestion will be highly appreciated.
Thank you once again

Navigation

[0] Message Index

[#] Next page

Go to full version