Eddie - Connections IR / US / Encoders/Motors problem

goupil35000

Hello,
I have 2 eddie platforms and I'm impatient to test them. But I have some questions before switching on.

1/ Connections IR / US / Encoders

When reading "28990-28992-Eddie-Robot-Platform-v1.3.pdf" (top of page 13), I think the good connections are these (see pictures).

I

(photo from 27971-Motor-Mount-Wheel-Kit-Guide-v2.0.pdf)


But when I read this forum, I saw Jessica Uelmen agrees this connection below is right (in thread "Problem of Eddie Robot Platform and Reading Encoder Data"Started by John ,Lin‎, 09-12-2013 07:26 AM,).

What are the good connections to begin -- I understand that there are 2 encoders, one with 90° offset -- ? If I look at the first picture on the right motor, it seems that there is only one connector -- and in my kit I have only 2 connectors of 3 pins for this (+2 others 3 pins connector for US).

2/ Motors
When reading this forum, it seems that at least one guy had problem with motors. When motors are switched off, can I turn them by hand or are they blocked ?


Thanks for reading until here ... and to give me good answers . Hope this will help others who begin with this robot ...

PS: my encoders are the blue ones.

goupil35000

I hope I'm right. I will switch on soon ...

Thanks.

RobotWorkshop

There are two different encoder styles used with those motors. The early ones were lower resolution encoders and those has a small mircocontroller onboard. You could daisy chain a couple controllers like the picture above. They had a single serial connection and you could talk to either one. They could also drive an HB-25 (or similar) H-Bridge so you can just offload the movement commands to those. These were originally used with the Eddie robot but it only used the encoder portion since the H-Bridge drivers are on the Eddie board.

Later on there was a new quadrature encoder board that had higher resolution encoders and provided the raw quadrature output. It looks like these are the ones you probably have. Those are connected differently. There should be something in the Parallax docs for Eddie that shows how the new versions connect. Also, since the Eddie board supports a couple different encoder options there are two different versions of the firmware and you'll need to load the one that matches your encoder configuration. I believe the latest version supports the hi-res encoders like the ones you have. You could also look at the source code for that to determine what IO pins to connect the encoders to. The newer encoders would connect directly to the Eddie board.

Robert

jkara

in the 1.1 version of the assembly manual on page 13, paragraph 2, the procedure is, and I quote:

Connect the left-most (towards the outer edge of the deck) three-pin cable from the left Encoder to
header pin 9 on the I/O section of the Control Board. The black wire should be on the outer-most pin of
the three-pin header. Now connect the other Encoder cable to header pin 10 on the Control board.
Connect the right-side motor’s innermost cable into header pin 11 on the Control Board, and then the
final Encoder cable to header pin 12. Be certain that all the black wires are oriented towards the outside
edge of the Board.

The left encoder is not the left as shown in figure 9b, but left as if you are behind the unit...
this took me a while to figure out... rookie mistake ...

Anyway, the proper way to hook it up, is as show in the following photo:

Hope this clears up some thing for other people as well..

Have fun,

jack