FYI Pi Ideas!

fly

omg
Oct 1, 2004
78,973
27,167
1,323
Marklar
₥83,289
Steam
mattressfish
So I found this the other day, and it seems like it would be a ton of fun. I've got a few Pis laying around here so I just might build this.

http://www.sandymakes.org/2014/01/triviabox.html

I bet there is some trivia service out there I could use to get the questions.

I also changed my PiHTPC from RasBMC to RasPlex. It's super sweet and now I can track everything I'm watching in Plex, just like everyone else who uses my Plex server!
 
  • Gravy
Reactions: Coqui
I have recently been wondering if a Pi could run an antilock brake system.

It would need to read wheel speed sensors and actuate relays controlling fluid solenoids on brake lines.

I think it could, but programming might be "fun"
 
I wouldn't use an RPi for an ABS controller... I seriously doubt you could achieve low enough latency with a linux system, not to mention get the appropriate wheel sensor and PWM signals in/out of the card.
 
@gee is probably right. Even with a preemptible kernel, latencies in Linux are... not small. Interrupt handling introduces non-trivial amounts of latency.

If you could get an RTOS running on it, you might get somewhere close to the ballpark, but nothing beats purpose-built hardware for that.
 
A point I had not considered. That sucks.
We can't really go with an off the shelf solution due to cost and it hurting us in the design portion of the competition. Building our own is the only real solution
 
Yeah, haul in some sparkies for this one. I think it'll make a pretty decent senior project for an ECE.

I'd start with a FPGA board to be honest - it'll let you divide up tasks pretty easily while keeping them walled off from each other, and latency can be made brutally low. Counting teeth on a wheel sensor to estimate wheel velocity can be done in its own HDL block... then instantiate four of those blocks inside another module that compares their outputs and computes an average vehicle speed, etc. Make other blocks for PWMing solenoids, starting up/stopping the ABS motor, etc.
 
  • Gravy
Reactions: Mr. Argumentor
So I found this the other day, and it seems like it would be a ton of fun. I've got a few Pis laying around here so I just might build this.

http://www.sandymakes.org/2014/01/triviabox.html

I bet there is some trivia service out there I could use to get the questions.

I also changed my PiHTPC from RasBMC to RasPlex. It's super sweet and now I can track everything I'm watching in Plex, just like everyone else who uses my Plex server!

Dude.

I host a bar trivia night every tuesday. I've got over half a year of trivia questions written up already.
 
Yeah, haul in some sparkies for this one. I think it'll make a pretty decent senior project for an ECE.

I'd start with a FPGA board to be honest - it'll let you divide up tasks pretty easily while keeping them walled off from each other, and latency can be made brutally low. Counting teeth on a wheel sensor to estimate wheel velocity can be done in its own HDL block... then instantiate four of those blocks inside another module that compares their outputs and computes an average vehicle speed, etc. Make other blocks for PWMing solenoids, starting up/stopping the ABS motor, etc.
Either that or look at the code in the megasquirt used for reading the teeth on a crank angle sensor. I'm not hep to those, are they Atmel/Arduino thingies, or something else?

In any case, I'm not sure I'd reach for VHDL right away, on account of the big transient states in voltage in a car environment. What I do remember about FPGAs is that, while they're incredibly easy to write code into, they're also incredibly easy to brick with oddball power states.
 
Either that or look at the code in the megasquirt used for reading the teeth on a crank angle sensor. I'm not hep to those, are they Atmel/Arduino thingies, or something else?

In any case, I'm not sure I'd reach for VHDL right away, on account of the big transient states in voltage in a car environment. What I do remember about FPGAs is that, while they're incredibly easy to write code into, they're also incredibly easy to brick with oddball power states.
Don't know too much about the Megasquirt guts.

Keeping FPGAs from bricking isn't too bad, it's a matter of keeping them on their own nice, well-filtered power rails and taking care that any signals coming in/out of the FPGA's power domain are well filtered. I spent 8 years poking FPGAs in high power radio broadcast transmitters, I'd rather put a FPGA in a car to be honest :)
 
Pi means Pimp in the streets
Darth Vader was the ultimate pimp. He wore a cape and his pimp hand was so strong he could strangle a ho from across the room.


iEFI8xf.jpg
 
Why have I never been invited?

Shit, I could have sworn everyone knew this by now. It's why I haven't been to WOB run nights.

Anytime y'all want to come out to Brandon (we know how THIS will go) to the O'Briens on a tuesday night, I'd love to have you all. We've got 10 pretty large teams that show up every week, and it's pretty competitive. Starts @ 7:15ish. Then when that is done, there is an 'after dark' dirty trivia at Linksters that starts @ 9:30 that same night.