RC Battle Spinning Top

So I've spent the last few days in my spare time designing the parts in CAD and then assembling it in Blender (Yes, the 3D modeling software).

I used Blender because it's a tool I've grown up with and I've had more success animating and manipulating 3D objects compared to Solidworks or Inventor. 

I will get this design printed out soon using a local 3D printing service and will post pictures here soon!

Since this toy will be remote controlled, the operator (the lucky kid who gets to play with this) will want to steer this toy in a direction of their choosing. The problem with this is having a frame of reference. How would the spinning top know which way is left or right, which way is forward. I could use a Gyro, but they're often difficult to take measurements from due to noise and offsets. Also, how will the servos react fast enough if they're also caught spinning all the time?

An Idea would be to have a motor that will drive the PCB to spin in the opposite direction. to match the speed of the spinning top itself but reverse. so that the PCB from the operator's frame of reference, would be stationary. By placing a marker on the PCB, this would provide an excellent way to tell the operator which way if forward, left right, and back. 
A problem to achieving this comes again to how well the Gyro is, whether it gets a sudden shock as the spinning top hits a wall. or if the filter isn't reliable and causes the PCB to slowly drift. 

A solution could be to use a series of Accelerometers to measure to measure centrifugal forces of the spinning PCB, and then applying speed to the motor to spin down the PCB so that it is stationary. Of course this is still an idea and research needs to be done to see if this is viable. 

Well, when I started with the design, I overlooked some mechanical details that would have rendered this toy useless or not as impressive as it should be.

One problem with driving the hemisphere with the outer body is: The hemisphere is not on a fixed angle, the angle will almost always change. Initially I thought about using a Universal Joint to transfer the rotation from the spinning top to the hemisphere. However, after some research, it was found that they suffer velocity fluctuations that is proportional to the angle from rest. So the more of an angle that is used, the more the hemisphere will slowdown and speedup. 

If this becomes a large enough problem, I've already designed a Constant Velocity joint to take it's place. I am worried about how much friction is being introduced though. so I've got both design ready to test to see how they go.