"yet Another Wall-e" (u-command Wall-e Teardown And Conversion)

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I bought this Wall-E about 3 years ago, and I thought it was the coolest thing. I played with it a few times, and shortly after, I began to get bored an thinking how cool it would be to turn it into an actual working bot.

I never really stumbled into anything that would get me hooked (Arduino was one idea when I got introduced to it a year and a half ago, but I was living abroad and my Wall-E was packed away, literally an ocean apart from me).

So a while ago I found EZ-Robot by accident (looking at Make and SparkFun websites for cool components to incorporate into my 2 robots - I also own a RAD v1.0, still sitting tight in the waiting room for his turn to get a makeover surgery) - and the first robot platform I saw being converted was this cute little brother of my long forgotten yellow friend, the Wall-E. Yaay! ;)

So 3 and a half years of waiting, and I am finally at the early stages of turning my old dream into a reality, by making my Wall-E sing and dance (and hopefully do more interesting stuff) under my command.

Last evening I started disassembling him, and in my first post I wanted to only document and share that part of the process with you. With a few remarks that I found interesting throughout. So I hope you enjoy and comment. ;)

Start of separation of base from main body:
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The back of the main PCB showing the "do-it-all custom processing unit" (or, as I call it, the "Big Blob of Black Plastic"):
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Yep. I was expecting to see something like that - it's virtually impossible to know what the hell is going on under that blob of plastic, unless I get an oscilloscope to look at the signals coming in and going out, and then if I can come up with a truth table for addressing the various sound samples stored in it, then perhaps I could reuse these instead of buying an MP3 trigger board from SparkFun.
(Of course, with a DSO203 handheld scope costing $200 bucks against $49.99 for the MP3 trigger, it's really a matter of dollars and cents against satisfying my scientific curiosity ;))

Couple more inside pics:
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The first thing I noticed is that there are only two motors in this robot - nothing else. All of his movements are coordinated via some very complex crankshaft gearbox mechanisms, activated timely by the big blob of plastic processing unit - one gearbox sits in the base, controlling the wheel movements (forward/reverse/turn/backward), and another is installed in the upper torso and controls the head rotation, eyes up/down and arms up/down movements. I have to tip my hat to the engineer who designed this. A whole lot of movements accomplished with just two ordinary DC motors. Unfortunately, these will have to go (although I am willing to perform some quick experimentation with driving the base gearbox, with the EZ-B board hooked to the existing H-bridge, just to see if I can simulate it going in all directions as I please. If I sense some kind of limitation, then it's definately gonna go.)

Finally, taken the upper body (head + arms) and torso apart
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Front view of the upper body (head + arms)
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Couple more views from upper body section
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Detailed view of the underside of upper body section, showing the hinges for the arms and the head rotating + eyes up/down mechanism (center)
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The arms are actuated by these linkages, which in turn are hooked to round actuators connected to the upper torso gearbox. When these actuators rotate, they drive the linkages to move side-to-side, thus driving the arms up/down. I was thinking, maybe instead of cutting the arms and gluing them directly to the servo head reusing these linkages and gluing the servos to the inside of the upper body section, to make the whole looks more unobtrusive. The same thing could be done to the head rotating and eyes up/down round linkages, it would be farily easy to attach a servo to it.

Side view, with close-up on the neck
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Here's the challenge: The neck is cast into a whole piece of plastic and in order to get the entire head to actually bend up/down, I would need to find a pivot point somewhere that I could attach a horn and link it to another servo, hidden under that section. As of yet, I cannot see a solution that would not involve gutting the neck (I think someone in the forums did something using the camera hinge, I may have a look at that and see if I could confidently replicate it.)
Troy
Commented October 2013
I'm sorry to hear you are having difficulty. From what I understand, you ordered from sparkfun without tracking. The first one was lost and they offered to send another for free also without tracking. If I may quote you "I'll take my chances with USPS thank you very much". I would have done the same because of the cost but you willingly will take a chance.
It seems that once mail leaves the US and arrives in the Brazil post system it gets intercepted. My guess is that they see it has no tracking and claim it for themselves. Im sorry that things are getting lost but sometimes it happens with untracked items.
Btw I too order internationally (China via Ebay) and items occasionally dont arrive and they offer to resend. I've ordered a Kindle Fire from Amazon the first one never arrived. They resent it but Im sure they would have sent a third though.
Rich
Commented October 2013
If it's a serial controlled board you are able to use EZ-Script to send the required commands, you can also map these to joystick buttons or key presses.

SendSerial() is the EZ-Script command and is pretty simple to use. With the documentation for the board I'm confident we can figure it out.

The board would need to connect to a signal pin of one of the digital ports, for instance D0. Then the EZ-Script command to play track 1 would be something like

Code:

SendSerial(D0, 9600, "P", 1)


I haven't had chance to read the document you linked to but hopefully the above gives you an idea of how simple it is.

WMoecke
Commented October 2013
Interesting point @Troy, let me ask, where do you live? And how much would FedEx delivery cost to you?
Try figuring these answers to yourself, and then ask yourself the question, would you still consider it fair for someone to pay almost 4 times over the cost of the goods just for having something delivered.

China does it easily. I get tracking. I get the goods. Not asking for more than that.

The thing is, as you pointed out, China wholesalers (I also buy from ebay, recently having successfuly purchased AND received an JXD S7300) DO send items WITH tracking.
American dealers "say" they sent, they "say" it should be on its way. Should I just trust their word, then.

USPS seems to be the poorest, lousiest, most incompetent posting service in the world. This is the impression I get.

@Rich: that example would be suitable for sending a command to the MP3 Trigger board. For the other board, it is done somewhat differently. As I mentioned, the commands are submitted from the macros embedded in the library files (.h files) included in the C source code. Thus, there are custom function calls placed throughout the example C code that take a single parameter of type byte to specify which file to play. Like this:

Code:

#include <SFEMP3Shield.h>
SFEMP3Shield MP3player;
MP3player.playTrack(byte trackNumber);


The files stored in the TF card are to follow a certain naming convention, in order for these macros to address the stored .mp3 files according to the argument passed to them. As in: 'track00x.mp3' ('x' = track number).

I haven't yet found anything that documents how the MP3 Player board takes serial commands as well as the PDF for the MP3 Trigger.
I haven't gone through the C# programming documentation for the EZ-board. Just as you, I got as far as figuring out that the RX connection gets a signal from the digital pulse output coming from the EZ board (just like it's done with the MP3 Trigger implementation), but the software part is what gets me confused.

Troy
Commented October 2013
I live in Qatar on a US base. Post goes to the USPS first before it's forwarded here and goes through Qatari customs. The tracking numbers I get from my China orders never seem to be real though.
USPS as with any government run agency never improve over time. USPS only got better when FEDEX and UPS offered better service and and cheaper. Here is one example of the mess.
Also Google USPS waste. I'm not really saying your wrong but things will get lost when going international. Well....in my own experience anyway.
WMoecke
Commented October 2013
It still amazes me how a country living under a comunist dictatorship is capable of considerably better postal service than a country that invests billions in warfare and international espionage. But hey, let me stop talking politics or I will soon need sedative. And this is not the place anyway.

I never found a Chinese tracking number to be bogus, hence me putting so much faith in them. But that's just me. Thinking about it, I only had negative experiences buying from the US. What can I say.
Robot
AvatarWMoecke
Published on Saturday, November 3, 2012