Monday, February 19, 2024

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:


Sunday, February 4, 2024

Lathe Spindle Motor Upgrade

Motor bracket laser cut and bent from .188" steel by SendCutSend:


Crufted NEMA-56-size Clearpath servo motor - integrated motor drive, plugs straight into single or 3-phase mains.


1:1 belt to the spindle:  




Pile of junk being replaced:


Spin-down comparison vs the original motor from 900 RPM:





Sunday, January 7, 2024

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:

 

Saturday, December 9, 2023

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.



Monday, November 27, 2023

Press Tool Trick

Picked up from a technician at work who'd pressed many a bearing:  Put a magnet in the back side of the press tool so it sticks to the bottom of the arbor press ram


Tool sticks to the ram and automatically squares itself!  No need for 3 hands to hold the part, the press tool, and the arbor press lever:



Installing some new bearings in a bike wheel front hub:

Sunday, November 5, 2023

Finally some lathe tool organization

3d printed dovetails - the AXA sized holders are just big enough to fit two screws into a 20x40mm aluminm t-slot extrusion:


 

Thursday, October 12, 2023

Hopper Stabilization Hardware Progress

 More little drone motors, flywheels, and motor drive mounting brackets:

New MJF printed structure to hold everything:



This is almost everything, shooting for 1kg total when it's done, not much left for the protective shells, foot, and control PCB.


Monday, July 17, 2023

Balancing Leg

It balances!


The inertia changes significantly as the "body" moves up and down the leg - for the controller, I got feedback gains with LQR for the maximum and minimum extension cases, and linearly interpolate between those gains as the leg extends.

Tuesday, July 4, 2023

Leg + reaction wheel doing stuff

Running off a bench supply and offboard micro, controlling with a joystick.  There's an IMU attached too, so hopefully soon it'll be doing some 1-DOF balancing:

Tuesday, April 18, 2023

New capacitor for Yottacoil

Another CPW, another round of tesla coiling.  Last time the primary capacitor caught on fire, so I helped Michael and Austin cobble together a new one out of the Eurofarad caps the coil originally used.  I designed some bus bars and MITERS undergrads got them waterjet cut for us.


216 M6 socket head cap screws and 36 crimps later:


Successfully ran 2 evenings with 0 capacitor fires and 1 boost converter fire: