20s Little FOCers on stooge SRB v5#1

[fessyfoo]

@shaman

So the v3.1 has different gate drivers, current sense amps, buck converter, IMU, and CAN transceiver. It also has more copper in the PCB for better thermals when pushing higher battery amps

so, i have lil focers v3.0 just learning about the difference on the newer v3.1
better thermals making me jealous.
but I still will push forward slowling figuring out this current setup.

[fessyfoo]

Dern, I procrastinated, and now i got myself stuck for testing day tomorrow.

put wrong fw on one of the lil focers (hw3.1 vs hw3.0 ) and I don’t have the version that was on it.

wanting 5.02 for hw3.0 if anyone has it.

and i’m confused what’s in the archive:

vesc fw archive has:

Little_FOCer:      5.03
Little_FOCer_V3:   6.00, 6.02
Little_FOCer_V3_1: 6.00, 6.02

tried the 5.03 from there but it has a hw limit of 175 ABS Current. so that’s not the one i was running, and maybe it’s for earlier fw versions?

anyhow pinged shaman. but stuck at the moment.

[bboybowzer]

They took away all the no limit firmwares in the archieve that might be why.

[fessyfoo]

There’s a no limit 5.03 for Little_FOCer. i’m just unsure if that’s for hw3.0 or something earllier.

[shaman]

You need to run the proper firmware version for the proper hardware version. Don’t run the v1 firmware on the v3 hardware. It won’t work at all

[fessyfoo]

yeah that’s why i stopped. i assumed the 5.03 firmware in the archive for “Little_FOCer” was not v3 firmware. sounds like that’s for v1.

[fessyfoo]

Ok,

Shaman confirms no 5.02 available for LittleFocer.

• I got fresh 5.03fw for hw3.0 installed.
• updated zero vector frequency ( that is “switching frequency” right? ). from 20khz to 30khz
• redetected motors. [ using vesc_tool 6.03, foc detect tab, default currents ]
• cut motor shafts, brought pinions in, narrowed rear slightly.
• rerouted motor wires so they aren’t dangerously near the spinning motors.

hopefully get some testing in wed night.

not much changed in the detection results. However the resistance for both motors came down from 23mΩ to 15mΩ ish on both motors. seems weird.

[fessyfoo]

@fessyfoo

• updated zero vector frequency ( that is “switching frequency” right? ). from 20khz to 30khz

I didn’t figure out much about switching frequency / zero conf frequency. so I’m trusting the guidance from @shaman here. I hope to understand better. My cursory understanding… is the switches will switch 50% more… so more heat possible. Second I postulate that should give better resolution generating the higher frequency wave forms needed at higher erpms. but… that’s almost pulled out of my butt. xD. links to good expalanations appreciated.

[fessyfoo]

@fessyfoo

Dash’s is geared for 48.9 which is why i was leaving it that way to compare.

so… no load speed of 57mph is quite a bit more than the 49 top i was expecting.
@DEEIF are you sure these are the 151kv? and not the 173kv? @Skyart any way to tell?

@Titoxd1000

Change the gearing for short track

yes tito.

[Evwan]

The teachers say their kv on the face that you bolt on

[fessyfoo]

@Evwan

The teachers say their kv on the face that you bolt on

hmm. have to wait till next time i pull it apart. they hvae 40mm to 30mm adapter plates covering that spot.

[fessyfoo]

@fessyfoo

• I got fresh 5.03fw for hw3.0 installed.
• updated zero vector frequency ( that is “switching frequency” right? ). from 20khz to 30khz
• redetected motors. [ using vesc_tool 6.03, foc detect tab, default currents ]
• cut motor shafts, brought pinions in, narrowed rear slightly.
• rerouted motor wires so they aren’t dangerously near the spinning motors.

So. the No load flutter appears to be gone. [Edit. it is not] Although it’s kinda scary to test running up past 85% dutycycle on “the bench” xD so much screaming gear noise.

@Skyart

Increasing your switching HZ helps your controller track your motor better, at least thats like the simple explanation for it

so is bumping to 30khz related to the no load flutter seeming to go away?

[Skyart]

Did you get 6.02 fw on there?

[fessyfoo]

@Skyart

Did you get 6.02 fw on there?

No, I’m sticking with 5.03 for robogotchi compatibility for now.

@fessyfoo

• I got fresh 5.03fw for hw3.0 installed.

[Skyart]

Its possible increasing you HZ helped with the flutter. Your MCU takes more current samples now so its able to more accurately run your motors

[fessyfoo]

maybe i’ll try switching it back to see if it comes back.

[zero_ads]

Any downsides to increasing the HZ?

[Evwan]

fet efficiency goes down, should drop your motor amps and more heat

[fessyfoo]

@Evwan

drop your motor amps

[fessyfoo]

wednesday sesh din’t happen.
Today’s i2s session got rained out.
finally dried up a bit i took it for some street riding.

@Evwan

and more heat

motors got hot quick. idk for sure if that’s just street riding. longer periods at higher speeds (30 - 37mph, 48 -59kph) but probably the 50% increase in zero vector frequency.

but, also the gearing.

don’t have good telemetry as robogotchi somehow doesn’t like the new fw even though it’s 5.03 still.
always a new problem. xD