Sadly, childhood eventually comes to an end. However, while growing old is mandatory, I am one of those who realizes that growing up is always an option. This might explain why I have that evil grin look on my face whenever I come up with inspiration or have an idea for a project that I really want to pursue. You know that look.
In this case, the inspiration came to me from a trio of television stars. Craig Ferguson, host of "The Late Late Show" on CBS; Grant Imahara, robot overlord and member of the build team on the Discovery channel series "Mythbusters"; and a fellow by the name of Geoff Peterson. Who is Geoff Peterson? Well, I define him as the result of:
I did not (and still don't) have any significant robot building abilities. If a robot building competition were to take place right now, Grant could show up and do nothing while I actually try to build even the simplest of robots and Grant would probobly kick my ass. You might be wondering about TIM and Chriton since they are both robots. That's true, but my creations were not robots. They were more along the lines of life-sized action figures.
To some level of surprise, this project did not pose as much of a challenge as I thought it would despite all that I was trying to accomplish with limited knowledge of the various subject matters. However, there were a few things that I knew I was going to have to learn and some things were easier to learn than others. I have not had any experience with some of the mechanics involved in robot building prior to this (including servos and possibly remote controlling them along with other components). I figured that I was either going to build a skeleton or turn into one trying.
The following will guide you through the adventues (and occasional misadventures) involved with my latest wacky creation. Keep in mind that this article was written as I progressed. Each day's entry was written at the end of the day things occured as opposed to writing everything all at once upon completion.
PRIOR TO BUILDING (June 7th to June 18th)
Good grief. I have not even started building anything and I am already running into all kinds of problems.
First, the card that I got which records and plays audio was an obsolete version. This came to my attention after noticing the card did not have features advertised in the instructon manual. It turns out I got the older card with an instruction manual for the newer version. I contacted Cowlacious Designs and they are not sure how I wound up getting the old card. On the bright side, I was informed that the card I was supposed to have gotten will soon be obsolete as well, the latest version of the card would be available near the end of June, and that I would be sent one as soon as they came in. I was also told the new card even has more features. I am going to hold on to the card that I have just in case I don't like the new one and will send back whichever card I do not use. I'm keeping my fingers crossed and hope they don't forget about me.
Secondly, the servo that was going to be used to move the head from side to side fried on me. I was fiddling around with the servo, microcontroller, and the servo controller software when I noticed that the servo was not properly responding to the valid positioning instructions that I had given it. I had sent an e-mail to tech support describing the problem and asking what to do. In the time it took me to compose that e-mail, the servo got hot enough to fry an egg on it. I picked it up and it burnt two of my fingers. I am honestly surprised that the servo case had not started to melt. It was that hot. I unplugged the servo and sent a second e-mail stating what had happened. As of this writing, there has been no response.
DAY 1 (June 20th)
In a hidden room buried deep inside a hollowed out volcano, I began work on what I would presently classify as a "distant relative" of Geoff Peterson. Despite initial setbacks, I was able to start some assembling of basic parts for the skull, neck, and chest areas. After laying out all of the materials I had gathered so far, I took a step back and noticed there was a lot of stuff to do here...and I have not even ordered the skeleton arms or legs yet. Dealing with the body parts is (in my mind) the simple part which I will get to later in the build. In the meantime, I started taking chest measurements. The chest plate is a 17" x 24" sheet of 3/8" plywood which will be reinforced with additional pieces of plywood later. After determining that I would need about 6" of space to accomodate everything from the neck up, I drew some lines, centered eveything, and positioned the "lungs". I know. Skeletons don't have lungs. Deal with it. The so-called lungs are just plastic pencil boxes that I picked up at a Dollar General store. These will house all of the electronics. I did test fit all of the electronic stuff earlier and everything fits nicely. After temporarily screwing in some spare pieces of wood from an earlier project to space and position things correctly, I drilled pilot holes and mounted the pencil boxes to the chest.
Believe it or not, that is about all I can do with the chest at this point.
The neck is just a piece of 1" PVC pipe that I picked up during one of my numerous visits to Lowe's. I had to somehow connect the PVC neck and the skull. I decided to use a PVC cap. I had to make the spinal cavity in the base of the skull a little bit larger to accomodate the size of the cap. I used my dremel to accomplish that need...and made a big mess in the process. To keep the cap in place, I drilled a screw into the outside of the skull, through the cap, and back into the inside of the skull. The good news is the cap is centered and level. I hope it stays that way because the bad news is that just as I got done tightening the screw, it broke. Hopefully, I will not have to remove it...or else it really will be a pain in the neck.
The skull is an assembled Scary Terry unit that I had ordered from Cowlacious Designs. I was originally planning to only buy the audio components from them, but when I saw that they sold the skull and saw how much easier it would be to hook all of the components together as opposed to assembly via my original plan, I went ahead and got everything I needed from here.
The assembled skull includes a servo that moves the jaw. I had drilled a hole in the spinal cavity cap so I could feed the servo wire down the neck and connect it to the microcontroller that will be housed inside one of the lungs. I will need an extension to make it reach but I was smart enought to order one of those when I orderd the replacement servos and other accessories.
DAY 2 (June 21st)
Because of my work schedule, I was not able to do a whole hell of a lot with the build today. I was able to get a couple of small details finished between work related tasks.
I put together the final piece of the mechanism that connects the neck to a servo. I will soon build the mounting bracket for the neck and another one for the servo that will hold everything in place. I will then be able to mount the skull and neck to the body. However, I will not be able to complete this task until the replacement servos arrive which should be on Thursday or Friday...I hope.
I also got a couple of questions answered.
First, I called ServoCity to find out what the hell happened to the servo that suddenly had the ability to cook dinner for a family of four. After explaining what had happened, the employee I spoke with admitted there was an undocumented instruction in the microcontroller manual. Apparently, there was a jumper on the microcontroller board that I was supposed to remove prior to use. With the pin in place, conflicting instructions were being sent to the servo.
Here is what I really don't get. Most stock hobby servos like this one have 90 degress of rotation. The servo I ordered was modified by ServoCity to provide 180 degrees of rotation. The jumper I was supposed to have removed is clearly marked "180 Degree Jumper Pin" on the board. Though not properly documented, you would think just by looking at those words that in order to get the full 180 degrees that the servo has to offer, you would have to insert the jumper on top of the pins. Apparently, it's the opposite. I was told that if all the servos in use by the microcontroller are 90-degree servos, keep the pin in place. If you have any servos that are not 90-degree servos (like the 180-degree one that I have...er, had), remove the pin. That sounds incredibly backwards and makes no sense to me. On the bright side, I do not have to worry about this problem anymore now that I know what to do. However, when the new servos arrive, I am going to call them up one more time to confirm whether or not to use the jumper. I have already had all kinds of problems and delays up to this point. Another pointless delay is the last thing on Earth I need right now.
Secondly, I needed to get power consumption information about some of the products that I ordered from Cowlacious Designs. The reason for this is that each component that requires electricity (three so far plus servos) comes with its own power supply that you would normally plug into the wall. The power supplies will add all kinds of bulk and weight that I do not really need...or want. What I decided to do is to get batteries (and a charger) that will power everything. I just need to figure out what the total power consumption of all my devices is. I have got all the numbers from other devices. Let's give Cowlacious Deisgns a call...
*picks up the phone, dials, and waits...and waits...and waits*
Would you believe it? A recording (which only played after about twleve rings and an assumed connection to a voicemail inbox) informed me that they are closed from the 21st to the 23rd with no reason specified. I know they recently moved to a new location but that was a couple of months ago or so. Oh, well. At this point, it's no big deal. I will not be able to go back to The Battery Terminal until the weekend. I am pretty sure I will be able to contact Cowlacious Designs by then.