KludgeGuru’s EEBlog

Click here to see the entire 3-Axis Talking Skull Project.

Well after months I finally started working on this project again.  I figured since Halloween is only a month and a half away I’d better get it done.

Graveyard skulls have put together some good construction instructions here:

• Motion Servo Assembly
• Jaw Servo Mounting
• Skull Plate Mounting
• Mounting the Eye Kit
• Hooking up the SSC-32
• VSA Programming 101

They also added a new Eye Kit for the skulls which I may add next year.

OK, now on to my first singing test.  I found a cool pirate song called “ I Once Wend Down to Kingston Town” by Amateur Hour – Pirate Copy.  The great thing about this song is that it is Open Source and covered by the Creative Commons license.

As with most of the 3-Axis skull projects on the net I used Brookshire Software VSA (Visual Show Automation).  It costs about $60 which isn’t too bad.  It also has a demo version but it doesn’t allow you to save all your hard work.  I eventually will write my own program to interface with the Playstation 2 controller but I have slacked off too much this year and will have to do that next year.

Here is a video I posted on YouTube:

Click here to see the entire 3-Axis Talking Skull Project.

I’ve started building my 3-axis talking skull using the Lindberg Complete Kit from www.graveyardskulls.com.  Unfortunetly GraveYardSkulls has not completed the instructions for this kit so I kind of had to make it up as I go.  The assembly is fairly straight forward but there are some parts I’m not so sure on.  I’ve started a thread on the GraveYardSkull forum about the instructions and Joel says he is working on them.  Look for updates here.

I’ve started the servo plate assembly.  The servos basically just slide through the rectangular cutouts and are secured using screws.  The back servo is also mounted with a bracket that will be connected to the servo rod later.

Here is the servo plate before installing the servos:

Here is the “bottom” view of the servos:

Here is a view that shows how the pivotrod bracket is attached:

Here is a “top” view of the servos on the servo plate:

Next I attached the pivot rod to the pivot rod bracket. There are three mounting holes in the bracket so the pivot height can be adjusted. I think it works best using the middle hole:

Next I attached the servos to the pivot rod using the pivot joints. I also replaced the circular servo arms with modified 180º arms. I basically just cut off half of the arm to make a 90º arm:

Here is a close-up of one of the pivot joints. The pivot joint arm is made using a threaded rod pressed into the pivot joint. The pivot joint is attached to the servo arm using a small pivot ball…it looks like a small version of a trailer hitch ball.

Well, that’s how I assembled the servo plate. I’m sure once GraveYardSkulls finishes their assembly instructions they will have more detailed pictures of the assembly process. Maybe when I assemble my 2nd skull I’ll take more detailed pictures as well.

I found a store that sales a 3-Axis Talking Skull kit…assembly required.   The store is www.graveyardskulls.com, they specialize in halloween animatronics.  They have two skull kits available, the Lindberg Kit and the Bucky Kit.  I choose the Lindberg for mainly two reasons, the skull is lighter than the Bucky and the kit was $25 cheaper.

I decided to purchase a pre-assembled kit for a few reasons.

1. Why reinvent the wheel.  The owners of Graveyard Skulls have put a lot of time and effort into the design.
2. I’m an Electronic Engineer not a Mechanical one.   I’m not all that good at mechanical stuff, although I probably could have figured it out.
3. I don’t have any experience with servos so it is nice to see how they are used first hand before I try to design something with them.

Here is what came in the kit:

This is a basic off the shelf Lindberg skull kit. It is white (unpainted) and some assembly is required.

This is the main portion of the skull. The nose bone is glued on front, the jaw attached to the bottom and the top of the skull just sits on top like a hat.

This is the top of the skull.

This is the jaw bone.

Here are the teeth & the nose bone that must be glued on. I’m not sure what the bone on the upper right is but it goes inside the skull under the brain. The kit also comes with a little stand so it can sit on your desk and stare at you all day.

This is a custom made acrylic plate. It fits snuggly inside the skull and the servos attach to it.

HiTEC HS-425BB Servo

HiTEC HS-325HB Servo

This is a bracket used for mounting the jaw server to the plate. There isn’t any holes pre-drilled for this in the servo plate.

Mounting Bracket that connects the pivot rod to the servo plate.

The pivot rod is what makes time travel possible…uh…wait that’s the flux capacitor. What can I say about the pivot rod…it pivots. The 3-axis servos connect to this.

Ball Links are used to connect the servos to the pivot rod.

Screws, they hold things together.

This is a threaded rod that is used to connect the jaw to the jaw servo.

Shorter threaded rods go between the servos & the pivot rod.

SSC-32 Servo Control Board. This controller can control up to 32 servos. It has an RS232 interface.

I don’t have a picture of the wire loom. They had production problems and are supposed to ship it out mid January. When I receive it I will update this post with a picture.

I do want to say that www.graveyardskulls.com has great customer support.  I ordered this kit before Christmas and it was supposed to be my Christmas present.  There was a misscomunication and it didn’t get sent out.  I called them after Christmas and Joel said he felt really bad so he threw in 3 extra Lindberg Basic kits (I ordered 3 additional skulls for future builds).  The basic kit includes the servo plate, pivot rod, mounting brackets and hardware.

This kit did not come with assembly instructions but they said they will have the assembly instruction posted on their website around January 20th.

Click here to see the rest of my Project: 3-Axis Talking Skull.

3-Axis Talking Skull – Project Index

1. 12-06-2008 – Project Introduction
2. 01-16-2009 – Lindberg Skull Kit
3. 02-01-2009 – Servo Plate Assembly
4. 09-13-2009 – First Singing Test