trying to assemble the jaw today. I just cut the bar for the servo. drilling holes for the servo now... but in looking at older geoff footage, looks like I'm missing a piece. The Servo seems to be attached to this metal bar on the jaw. the back of it holds the skull to the top of the jaw. the middle part is where the servo is attached, and somehow it all rotates together while holding in place...
What the...?!?!? I just checked out the link and realized...that is MY robot. Well, the old version of him anyway. I believe that video is from 2012. I have since constructed a new body made of Actobotics parts and is now far more functional than this model ever was. For the most part, the wheelchair motors worked like a charm but was not the most worthy mobility related solution in the world. I still have the platform and wheelchair motors which I might re-purpose for another project. Thanks for the mention.
no problem! twas very cool! I'd love to see photos of how you got the arm attached, and hooked up the servos to raise the arm. I'm still not sure how i'm going to hook everything else up, but at least we have a tutorial for the jaw servo.
Geoff Got painted yesterday, so he's proper white. Will probably sand it a bit, as my bad painting skills are legendary around these parts.
I will be ordering a full skeleton soon. the arms went out of stock since I found them, so I Guess that's my only option left.
Also, I donated to josh robert thompsons JRTV campaign and will get a custom geoffry peterson voice mail. If anyone can think up some funny things for him to say that would make him unique to my geoff, will gladly take suggestions ;o).
Here are the best pictures I could find of how the arm was attached to the body. Go ahead and laugh at the plywood. This version of the body has been done away with.
The mechanism is a servo gearbox that I purchased from ServoCity. I added a shaft extension which connected to a clamp that was attached to the arm. The current version of the body is made of Actobotics parts (which is far more flexible) and there are servo gearboxes that are designed to work with Actobotics parts. The entire gearbox allows for 180 degrees of rotation. When the arm is down (as pictured), the servo is centered so it can travel 90 degrees in either direction. However, in my case, the servo is programmed so that it will not travel backwards. I will be making some videos demonstrating the functionality of this new version of the robot. Just do a search for "Fergybot4000" on YouTube and you should be able to find the ones that are there now (including the one you referenced earlier).
and something like this to get the head moving. all in measured sizes once I figure out what that is ;o). although not quite sure how you'd secure the motor in. you probably couldn't drill a hole in it's base without wrecking it.
It looks like the arm is pretty easy to hook up too once you find t he proper metal rod to hook it all up... I guess I can use my spare syren ten from R2 to control it.
I know nothing of programing...
I currently use a Lindberg skull because of its light weight. Bucky skulls (which is what I believe Geoff was made with) are heavier but I have used a Bucky skull (as shown in my earlier pictures) before and it was not a problem though I did use a slightly more powerful servo for the neck, which lasted about four years before I had to replace it.
Lack of position feedback is one of the two main reasons I would not use gear motors. Like Geoff, I have wires running from the microcontroller up into the skull (to control eye colors and the jaw servo). Using a gear motor would just invite the possibility of getting all the wires twisted around the neck shaft if one was not careful. With a servo, I would be limited to a maximum rotation of 180 degrees (90 degrees from center in both directions). However, if you have no wires going into the skull and you want to freak somebody out with a head that can spin around in circles, then perhaps a continuous rotation servo is in order.
By the way...upon further review, it just dawned on me that the specific SparkFun parts you listed in your earlier post will not connect to each other at all. You have a 6mm shaft coming out of the gear motor which you would try to connect to a 1/8" coupler which you would try very hard to connect to a 1/2" piece of shaft tubing. Good luck getting that to work. While we're at it, let me know if you figure out the whole space time continuum thing so I can finish work on my functional TARDIS.
On a more serious note, a few more things came to mind.
1) Can you tell me what you were thinking about using for a chest plate? Geoff uses an aluminum plate and mine uses a sheet of 1/4" ABS plastic. I imagine mounting all of the hardware to an actual skeleton would be somewhat tricky.
2) I noticed you mention a "tutorial" regarding Geoff's jaw. I don't know if this is what you encountered, but I did see some sketches that Grant drew up when designing Geoff (see below) and noticed that the setup that he draws is NOT what eventually got built.
3) Upon reading your earlier post again, the parts that you listed were in reference to the arm, not the neck/head, which is what I discussed in my reply. While my observations regarding the parts that you listed not being able to connect to each other are true, my response regarding a potential way to create the neck/head mechanism is still valid. ServoCity no longer manufacturers some of the parts that I used at the time to create the arm mechanism. The updated version of the setup would be as follows:
I do realize that you are not at all obligated to follow any of these methods in building your Geoff. However, this is information and I do not mind offering my two cents worth. I don't want to feel like I am forcing any of this on you.