I got a question regarding the LYNX robot arm

Help & Support Robot Parts
1

I am reffering to “Robot arm remote control interface” which can be seen here: youtube.com/watch?v=58DIp7NblzU

I was wondering how this was made.
Did they have two exact same robot arms with the same servoes on both arms?
If I should use a servo on my controller arm, how should I do that?

-Alex

2

The principle is actually quite simple: the arm which is manually controlled simply provides the angle of each joint.
The “feedback” arm in the video uses modified servos in order to get the value from the potentiometer inside the servo.
This approach means the feedback arm looks exactly (or can look exactly) like the arm being controlled.
If you want something even more simple, but just as effective, you can create a purpose-built feedback arm using only potentiometers:
youtube.com/watch?v=F-5-ymKTiMU
Specifically: youtube.com/watch?feature=p … KTiMU#t=72
You will need a microcontroller with enough analog IO pins to read all of the joints, but a normal Arduino can take care of that, as well as controlling the real arm.

3

Thanks man!
How can this servoes be modified so I can get the value from the potentiometer inside the servo?

-Alex

4

When you open the servo, you’ll essentially see a small rotary potentiometer. You have two approaches:

  1. try to add wires to the potentiometer so you can get the analog value, but still have a useable servo. Unfortunately we don’t have a procedure for this.
  2. cut the wires to the potentiometer and solder new ones, essentially making the rest of the servo (aside from the case) unuseable.
5

Thanks!

I will give it a try.

Have a great weekend.

-alex

6

Is there any rotation/position sensor which can be used in this case?

7

Nothing specific; we suggest a 5V rotaty potentiometer.

8

Is there anything you would recommend that are not so expensive?

9

We mostly provide breakout boards, which may help with mounting:
robotshop.com/en/electronic- … =RB-Ite-06
You can create a “sensor arm” using normal materials, a saw and a drill. You can create a really nice one if you have a 3D printer.

10

Ok thanks :slight_smile: