9th January - 23rd February

It's been a while, but quite a bit of progress has been made.

Research

Nothing really on the research front, the focus has been more on getting models built and stuff made :)

Rigs

An additional rig has been designed. This will allow for the measurement of magnetic field strength (flux density) from my device. Hopefully this means that in the event that my device doesn't turn I can at least show I am on the right track.

Also I have started to produce parts of my Rig using the IForge makerspace at Sheffield Uni. Pretty great place not going to lie.

^Lots of holes

^Oooo what lovely blond hair that experimental rig has!

Analytical Calculations

In the last log I claimed that this would only take a number of days to complete....... 

Almost two months later I now have a pretty robust analytical model for predicting the performance of the spherical drive system. Here's a graph!

-The attentive amongst you may realise that the Torque value is not especially high. In fact it is concerning low, hence my back up plan of a magnetic field measurement device to prove that my plan (sort of) had potential.

Electromagnetic Simulation

Did give this another crack but my model is throwing up a lot of errors that seems tricky to fix with only the guy on YouTube to look at for help. I think I might endeavour to find someone at the university who knows how to use this software.

Power Supply

My solution to this problem, which I had encountered just before the last log entry, is to use an Arduino Mega instead of an Arduino Uno to generate the power.

This should be possible on account of the additional timers that the Mega has when compared to the Uno. 4 available timers versus 1 timer. (There are more timers on both boards but they are required by other functions).

The Mega will then act to control 3 Arduino motor shields, offsetting the phases by 120 degrees each. Each board being powered by 3 independent 12V Voltage sources (i.e. 8 AA batteries in series).

Upcoming Dilemmas 

Dilemma #1 

- The time is fast approaching to start building the stator. This will require me to go to some effort and expense purchasing steel sheet and using the water jet cutter to cut it out.  The problem is that the relative permeability of the steel is the key parameter, the values of which vary wildly depending on the grade of steel in question and it is a property which is rarely considered by most suppliers of regular (i.e. cheap) steels. Therefore I have no real guarantee as to what the relative permeability of whatever steel I purchase is. This is something I need to fix, perhaps there is a supplier of stator-grade steels at the university?

Dilemma #2

- I really have no idea if my Mega powered 3-phase solution will actually work, or if my code is any good.

Dilemma #3

- Time! this thing has to finished by like April! :O! Crikey!