Robot Scorpion Tank

I decided it's time to build myself a DoomsDay Machine
So i'm building a Robot Scorpion,,,,
An insane 23 Degrees of Freedom of movement, (3DoF Legs, and a 4DoF Tail).

Why? , Because i can !!!





Parts list...
-23x "15kilo torque digital servo's",
-23x "Aluminum Servo Horns",
-1x "32 channel servo controller" + "BotBoardDuino"
-1x "PlayStation 2 wireless controller",
-3x "5.8ghz FPV video systems"
-1x "3 Channel Remote Controlled Video Switch"
-2x "Castle Creations 10amp BEC's"
-32x "Universal Mounting Brackets (Long, Short, Thin, Wide, and Angled)"
-1x "Heaxpod Main Body Frame"
-12x "Hexapod Legs Panels"
-12x "Hexapod Feet"
-300+ Screws, Bolts and Nuts....

100+ hours of programming the robot controller to handle "Inverse Kinematic" walking gaits with a 4DoF tail.


Video's of final assembly and functionality coming soon........

Will your controller only use "blind" inverse kinematic, or are you going to use sensors for feedback (like IMUs or contact sensors on the legs)?

I'm starting off blind, then i'll move to buying Dynamixel servo's with Bi-Directional TTL communication and PID loops to improve upon the servo controllers awareness of where each joint is positioned.
Edit..
I like the Dynamixel MX28T servo's, so if everything works really well i'll think about investing in 18 of those next

Is this you?

Spoiler: I don't get it

So this?



2:50

Aww i can't watch it, it says "Fremantle International have Blocked this video in your country" and some other copyright pooo

Geez, copyright laws are getting stupid..


Was it this ??

Baby's First steps..


Sorry bout the poor quality video, i only have my phone to record until my camera recharges..
I made this video just to show my baby's first steps..
I'll record a Better quality video tomorrow when i can find a camera man, then i can exert more control over the robot and demonstrate more of it's functionality..

Edit..
It's very difficult to control one handed i made the controls very similar to a Dual Analogue First Person Shooter, with walk forward and strafe on left stick and look up/down and rotate on right stick.

Ah, good ol' stable tripod gait

I have about 8 gaits programmed in..
Normal tripod gait (by far the fastest gait for moving around)
3 variations of the tripod gait, but in 3, 4 and 5 step ripples.
2 variations on the 2.5 step walk (Front and rear legs step twice, middle legs step once)
1 Wide step tripod gait (Legs lift very high and femur's swing the tibia outward to increase step height)
2 variations of the single leg step gait.

If your familiar with IK gaits then you probably know that about Kåre Halvorsen's (aka. Zenta) Phoenix Gait system,
I'm using that as a base for my IK system..

I'm impressed.
Unfortunately I'm not particularly familiar with all of the walking patterns, but I worked in a place where they had a few crazy people working on a hexapod robot base. And it was always fun to watch those things walk.

Almost finished



Features..
3 DoF Legs
3 DoF Tail
Body mounted "Fatshark FPV video system"
Tail mounted "Mobius Action Camera"
Inverse Kinematic Walking and Tail control.
Full tail control while in motion.
+ more

New video's coming soon with even more improvements.
I have removed a lot of the Audible Beeps i used for Debugging purposes since this video and also re-written the control mappings to better suit how i want the "Beast" to handle.

Now you just need to increase the size tenfold and strap some guns onto that baby and you've got a modern day terminator military weapon.

To be honest i seriously thought about that idea..
But the big downside is, As the size goes up the weight increases exponentially.
At it's current size 50cm squared it weighs in at 2.7 kilo, if i was to make it say 1m square it would weigh in at close to 7-8 kilo, and at the size of a sedan it would probably weigh over a ton or more.
Now the weight itself isn't to much of an issue but the power required to drive a large mass like that is the killer..

Dang, such a terrifying thought.... an 8-legged robotic beast the size of a sedan. AND equipped with weapons.
Ima go hide under my covers now...

There's already 2 out there in the real world and both weigh over a ton.. but they are unarmed...



And ..

Yeah, for now!

I'm just sad nobody got the Fallout reference .

And here is a more "commercial" version

This thing can walk on the sea floor.

But to what depth?

I'm not sure. They plan to use crabbster for rescue work on shipwrecks and maintenance work on oil platforms where currents are to strong for scuba divers. So I would guess a few hundred meters at least.
There is a rather old ieee spectrum article (from 2013) available: http://spectrum.ieee.org/automaton/robotics/industrial-robots/six-legged-underwater-robot-crabster