And We're Back

It has been an eventful year.  I'm finally back to working on projects.

After some firmware fiddling, the new drive units are finally spinning, driven by the kart's original gen 2 Prius-based inverter:

Spinning Drive Unit

 

Slapped a mini cheetah motor drive on there to make it go

Assembled Rotors

That's looking like a drive unit

 

Missing a rotor

Machining a new shaft for the rotor:

Improvised chip deflector for roughing

nice

Other side done

bearing and lock ring test fit

Next to the stock shaft.  Going for a normal press vs the straight knurl on the stock shaft.

I don't own a 2d printer and didn't plan far enough ahead to print the drawing at work, so this happened

Stator Assembly

 Stators shrink-fit into the housings:

Machining fixture turned into a guide fixture for the shrink-fit operation

Band heater wrapped around the housing to keep it hot while installing the stator:

Borrowed the pneumatic powered hydraulic press at work to make sure the stators didn't get stuck half way down:

3D printed 2-axis flexture kept the stators parallel to the housing but allowed them to center to the housing bore:

More motor housing machining

 

Printed Motor Housing First Post-Machining Operation

Printed plastic expanding mandrel to hold the part from the inside:

Around .005" TIR on the as-printed surface after clamping from the ID.  Not too bad.  This all gest machined away anyways.

Checking the lock ring fit after machining the threads:

Rotor bearing and lock-ring test fit:

Sneak peek of what's coming:

 

Machining some lock rings

 

Big Kart New Beginnings

After brining it to the BD car show in 2022 and remembering what a blast it was to drive, I got interested in working on the Big Kart again.  It's getting new everything, starting with drive units based on the newer Ioniq hybrid HSG.  Real blog post when I've made more hardware progress, but for now enjoy this picture of some 3d-printed aluminum motor housings with internal water cooling channels. All the way on the left is the stock housing.

More Screw Mechanism Testing

 Now controlled over CAN and USB, using a gui based on the espresso machine software

The the USB communication plus Python GUI gives me nice live-plots and logs.  Here's a plot of the fast position steps:

Ioniq HSG