THe NAC Lots-O-BFG KO2 Thread

[5spd_xj]

Re: THe NAC Lots-O-Post Thread

Looks like the snow is slowing down a but more now. I should plow so you're lame ass can get in the driveway:laugh3:

ah you tawkin ta ME?

I'll be fine. Leave it.

 

[vetteboy]

Re: THe NAC Lots-O-Post Thread

He went one step further and cut the whole unibody off instead of only 2/3 of it.

zing! :laugh:

 

[ktm racer 419]

Re: THe NAC Lots-O-Post Thread

Sam, I see you viewing this thread... is your jeepy cruisable yet?!?

just needs a driveshaft and while i got it in here with the flooids outta the brakes ima redo the brakelines on the 60

Some piece of junk 2 door will probably pop up on craigslist in a week and i'll own an XJ again before my old one is even out of the driveway

i still have my white one.

i should prolly get rid of it soon

 

[XJLI]

Re: THe NAC Lots-O-Post Thread

i still have my white one.

i should prolly get rid of it soon

yeaaaaaaaaaaaa

 

[kastein]

Re: THe NAC Lots-O-Post Thread

i still have my white one.

i should prolly get rid of it soon

I still haven't driven over the damn thing!

if your slacking/procrastinating skills continue to exceed expectations I may get a chance to if I finish the M54A2 soon.

 

[XJLI]

Re: THe NAC Lots-O-Post Thread

i just took my 3rd dump today. it's how i stay skinny. it's like i'm bulimic, but with poop.

 

[billyjp2]

Re: THe NAC Lots-O-Post Thread

i just took my 3rd dump today. it's how i stay skinny. it's like i'm bulimic, but with poop.

all pretty similar in size?

 

[MoparManiac]

Re: THe NAC Lots-O-Post Thread

$1350 for all the full hydro stuff and a derale tube/fin cooler shipped to my door.

Why are jeeps so much money...

Thankfully that's literally everything I need to get the steering done minus a reservoir bracket and some fluid.

 

[kastein]

Re: THe NAC Lots-O-Post Thread

Why are jeeps so much money...

"the only difference between men and boys is the price of their toys"

 

[vetteboy]

Re: THe NAC Lots-O-Post Thread

Tech geeks, this is pretty cool:

http://www.dump.com/2010/11/25/double-inverted-pendulum-video/

We had a single-inverted pendulum that we played with in my control systems classes, but that one's just badass.

 

[XJLI]

Re: THe NAC Lots-O-Post Thread

all pretty similar in size?

#2 was significantly larger, and definately contained the two crunchy beef burritos with lots of fire sauce i consumed last night. 1 & 3 relatively smaller.

 

[billyjp2]

Re: THe NAC Lots-O-Post Thread

http://www.fastenal.com/web/products/detail.ex?sku=0854060&ucst=t

I can get this at a pretty sweet discount. I don't know what to look for in a torch setup, can anyone offer some advice?

 

[kastein]

Re: THe NAC Lots-O-Post Thread

Tech geeks, this is pretty cool:

http://www.dump.com/2010/11/25/double-inverted-pendulum-video/

We had a single-inverted pendulum that we played with in my control systems classes, but that one's just badass.

now that I think about it, this might be something you're interested in. My senior project was a gantry crane control system that would move a load from position A to position B without it oscillating when the load stopped. Basically an inverted pendulum.

Sadly, I am good at embedded systems design and suck horribly at stepper motor controller design. Got everything built (I designed the entire thing from schematics to PCB artwork to mechanical fabrication) and then spent months learning how not to build stepper motor drivers. It literally set something like 800 dollars worth of MOSFETs on fire over the course of the project, and never did work. We even blew up a COTS stepper driver that had a 400% safety margin and claimed to have thermal overload protection... via thermal overload, after 20 minutes of testing. Next time, I'm using servos, and leaving the power electronics stuff to someone else.

The PCBs were a work of art and the control system thought it knew what it was doing, though :roflmao:

 

[foxwar71]

Re: THe NAC Lots-O-Post Thread

Well then get going if you think you can make it.

Okay fine.

I just don't want him to pull an Anthony and disappear completely.

When was Anthony's last wheel? 1.5 year yet?

$1350 for all the full hydro stuff and a derale tube/fin cooler shipped to my door.

:thumbup:



Im gunna send my box to PSC and have them overhaul it like Chris'. The dual pathway spool valve thingy sounds like the bee knees.

 

[foxwar71]

Re: THe NAC Lots-O-Post Thread

I just covered about 5 miles on the mini bike doing a loop around the streets in the north part of my town. IT BROUGHT THE FUN!!!

 

[JrTxJ]

Re: THe NAC Lots-O-Post Thread

something about Ross on a mini bike just cracks me up.

and with that said, I'm leaving work.

 

[XJLI]

Re: THe NAC Lots-O-Post Thread

I just covered about 5 miles on the mini bike doing a loop around the streets in the north part of my town. IT BROUGHT THE FUN!!!

UGH i wish mine was running :sadface:

 

[vetteboy]

Re: THe NAC Lots-O-Post Thread

http://www.fastenal.com/web/products/detail.ex?sku=0854060&ucst=t

I can get this at a pretty sweet discount. I don't know what to look for in a torch setup, can anyone offer some advice?

I have no idea, but I had a meeting with somebody from Fastenal yesterday to talk about their manufacturing and machining services. We've been buying things from Fastenal for years but I never knew they did that kind of stuff. Got a few parts out to be quoted right now...I was surprised at the capabilities they had.

now that I think about it, this might be something you're interested in. My senior project was a gantry crane control system that would move a load from position A to position B without it oscillating when the load stopped. Basically an inverted pendulum.

Sadly, I am good at embedded systems design and suck horribly at stepper motor controller design. Got everything built (I designed the entire thing from schematics to PCB artwork to mechanical fabrication) and then spent months learning how not to build stepper motor drivers. It literally set something like 800 dollars worth of MOSFETs on fire over the course of the project, and never did work. We even blew up a COTS stepper driver that had a 400% safety margin and claimed to have thermal overload protection... via thermal overload, after 20 minutes of testing. Next time, I'm using servos, and leaving the power electronics stuff to someone else.

The PCBs were a work of art and the control system thought it knew what it was doing, though :roflmao:

Stepper motors were the guts of my final project for a Mechatronics class - we had to make a machine sort of like a computerized etch-a-sketch. I got along OK with those.

My nemesis was digital potentiometers. I was using one (again in conjunction with a BASIC stamp) to control the speed on our autonomous vehicle - the drive motor was out of a Rascal scooter, and speed was via a PWM controller. I wanted to use a digital pot to replace the 'throttle' control from the scooter.

In theory, the BASIC stamp monitored 5 inputs (4 speeds and a stop command), and whenever one of the inputs was triggered, it would flip the write pin high on the digital pot and pulse a bit sequence...I think it was probably 8 bits, and it scaled the resistance appropriately. This worked great on the bench but whenever I coupled it to the PWM controller it'd melt the chips right away. I never figured it out and ended up just mounting a standard pot on the side of the vehicle, so you just set it manually like a cruise control, with a relay to kill the PWM controller to stop it.

Bitch of it was, I had accidentally ordered surface mount chip packages instead of something a little more workable. I managed to use the 15-watt grounded soldering iron from Radio Shack (and 2 or 3 beers for a steady hand) to stick them to some boards...interesting task.

The digital compass was a whole 'nother fiasco...ever write in Matlab? That's a story for a different day.

 

[billyjp2]

Re: THe NAC Lots-O-Post Thread

I have no idea, but I had a meeting with somebody from Fastenal yesterday to talk about their manufacturing and machining services. We've been buying things from Fastenal for years but I never knew they did that kind of stuff. Got a few parts out to be quoted right now...I was surprised at the capabilities they had.

I've been here for 5 months and still have no idea about half the shit we do

 

[kastein]

Re: THe NAC Lots-O-Post Thread

Stepper motors were the guts of my final project for a Mechatronics class - we had to make a machine sort of like a computerized etch-a-sketch. I got along OK with those.

My nemesis was digital potentiometers. I was using one (again in conjunction with a BASIC stamp) to control the speed on our autonomous vehicle - the drive motor was out of a Rascal scooter, and speed was via a PWM controller. I wanted to use a digital pot to replace the 'throttle' control from the scooter.

In theory, the BASIC stamp monitored 5 inputs (4 speeds and a stop command), and whenever one of the inputs was triggered, it would flip the write pin high on the digital pot and pulse a bit sequence...I think it was probably 8 bits, and it scaled the resistance appropriately. This worked great on the bench but whenever I coupled it to the PWM controller it'd melt the chips right away. I never figured it out and ended up just mounting a standard pot on the side of the vehicle, so you just set it manually like a cruise control, with a relay to kill the PWM controller to stop it.

Bitch of it was, I had accidentally ordered surface mount chip packages instead of something a little more workable. I managed to use the 15-watt grounded soldering iron from Radio Shack (and 2 or 3 beers for a steady hand) to stick them to some boards...interesting task.

The digital compass was a whole 'nother fiasco...ever write in Matlab? That's a story for a different day.

SMALL steppers I get along fine with. The sucker we were driving was nowhere near small though - it weighed around 5lbs, and could make our 15lb aluminum gantry crane "cart" peel out, that is, when it wasn't busy smoking the motor controller.

Basically, I got a crash course in thermal protection, H bridge design with driver dead time control, inductive load control, etc. An electric motor acts like a very easygoing resistive load when it is being driven with the proper amount of power, but if you just keep pouring the same amount of power into it whether it's fully loaded or idle, it acts like an inductor at low load and retaliates by zapping the crap out of your poor driver circuit.

I would be willing to bet a case of beer that your problem with the digital potentiometers was relative voltage - your control circuit and the circuit it was controlling were not on the same reference, and the digital potentiometer chip ended up sucking up the difference and going up in smoke. The problem is that the scooter controller probably used the original throttle pot on the high side of some circuit (i.e. tied to VCC/VDD) while your control circuit was trying to use it ground referenced :explosion

Yeah, soldering surface mount is fun. I can handle down to 0402 chip resistors with no magnification and a regular iron, beyond that it gets hairy. 0201 size parts are the devil.