Breaking the vim addiction

alias vim='open -a Sublime\ Text\ 2.app'

Pointless

What's the point of ponying up roughly $150k - 200k to go to a school such as MIT, just to get a job that pays only $100k/yr without much room to expand -- say $250k/yr max? It seems like the same could be accomplished by going to a state school on a full scholarship and saving the money for a nice car.

Working in the Terminal

A couple years ago, I read an article about relying more on the terminal as a way to decrease distractions, thereby increasing efficiency. I finally took this guy's word and spent the past week moving my email and messaging routines to mutt and irssi-xmpp respectively. The programs are running in screen on a server.

In addition to being a command line hipster (ha :P), I can save a small chunk of RAM from not having Gmail as an open tab in Webkit. This is especially helpful for running Lightroom, which enjoys gobbling system memory. Sure, this workflow has limitations (attaching files to emails, for example), but it's a small move that I hope will ultimately wean me off my attachment to electronic communications.

Happy Valentine's Day!

How many bites can YOU take out of my heart?

KawaiiKart: Mechanical Assembly DONE!

Alright. This is the third-to-last post that ends the KawaiiKart saga! I am extremely naive, at least considering my current trajectory. Actually the aforementioned claim seems fine, since all I have left is getting the EV section to run, then the gas engine to run, and finally coordinating the two!! I will detail the assembly of most of the kart, from most of the steering assembly to mounting the engine.

MLK weekend

Remember from last time that I messed up the steering knuckles? I got a chance to re-waterjet my parts (on campus! no week-long delays!) with a nice Omax waterjet. Unfortunately, there were no 0.25" thick aluminum sheets that were large enough, so I was going to make twice the number of parts on a 0.125" thick sheet.

It's a $400,000 printer that takes sheets of aluminum!

At first I waterjetted on quality 4 (second best), but the waterjet's software said that it would take an hour as well as 50lb of abrasive. I decided to let it run for a while, but I realized that my routing did not include small tabs on the parts (to prevent the parts from falling into the waterjet tub), which the second part did. At this point, I stopped the waterjet, added tabs to my parts, and reran at quality 3. The run time and abrasive consumption were much more reasonable, clocking in at 14 minutes total and 7 lb of sand.

The new knuckles turned out to be perfect. At this point, I was supposed to have a rolling frame, but by virtue of sloppiness, I forgot to order 3/8"-24 nuts, some steering column lock collars, as well as more L joints for the tie-rod steering.

Better waterjetted steering knuckle: the nut fits!! (of course I winged it)

Vise-ing bearings into steering mounts.

The legendary T-nut.

Assembled frame!

My temporary parking space at MITERS.

Charlesg welded my unidirectional flywheel tight.

Testing the fit of the wheel axles.

Taking a break to track ChibiKart in the snow. This is the result.

Mounting the steering knuckles.

An engine and wheels appeared!

Servicing engine mount with a makeshift carjack.

Week before Techfair

This is the week when the EVERYTHING happens. Literally. It's the last week of my externship, Battlecode quals + finalists' dinner + final tournament, and KawaiiKart cram week. Basically all the time after work was dedicated to either writing code for Battlecode or working on the go-kart. During this week, I went from chassis and parts to a mostly working kart. Picture dump below:

Scraping self against a piece of aluminum or Nancy's hexapod.

Using vise as holder to insert one notch into motor mount.

Vising entire motor mount into steering knuckle.

Chibi motors!

Mounting motors onto motor mount.

The bore of the pinion gear is slightly too large, so we'll pad it with Coke can.

Too lazy to file deeper notch in motor shaft.

Adjusting pinion gear on motor shaft.

Motor on wheel!

I fail at ordering parts again.

It's a masterlink!

Cutting fluid does wonders.

The chain is on! Now to tighten it a bit more.

Steering column with tie rods!

The MITERS parking garage.

Side profile.

My hands turn black after a day's worth of hard work.

BigLathe!

Motor controller (it's a Kelly controller).

Revised steering column end mount.

That steering wheel was not intended for this vehicle.

Soldering the Hall sensors onto those boards was really annoying!!!

Last but not least

The correct way to listen to K-pop is to turn the bass all the way up, and then knock the treble down a few notches to compensate.

Up next: electronics and a working EV!

KawaiiKart: December/Early IAP Update

I spent most of yesterday night working on KawaiiKart. In fact, I promised myself not to leave MITERS until the rear wheel was on the chassis. This is more complicated than it sounds because I screwed up assembling the rear of the kart twice!

My first problem was that the distance between the aluminum extrusions was too wide. Turns out you must take into every little dimension when CADding parts. Since I normally work with things that have infinite tolerance (code/math)...go figure -_- The solution wasn't too tricky; I made two plates that went on top of the extrusions that connected two more extrusions on the respective insides.

This solution introduces more torsional flex, but to what extent is unknown so far. It seems to pass a rudimentary twist and sit test, though.

The second issue dealt with how my rear wheel was installed. Since I had the wheel essentially slide into the space between the aluminum extrusions, I couldn't tighten the bolts if I first installed the extrusions onto the chassis.

Here's to hoping I tightened the bolts enough such that the wheel won't fall off during operation!

I also had a slew of smaller issues, like incorrectly measuring dimensions and not accounting for dimensions and the like.

Because the axle diameter isn't 5/8"; it's really 10mm!

Because T-nuts have finite size

Because axles have finite length and need to be secured...somehow.

That's all for now! Hopefully I can have a rolling frame (with motors!!) by the end of MLK.

Happy 2013! / 2012 in Review

Happy New Year! I don't think I've made many nontechnical posts recently so here's a treat for everyone.

First up: New Years Resolutions (not in any particular order).

• No more computer purchases unless they will be arbitraged.
• Focus -- learn to say no.

and lastly, finish your scooter!

Next, year in review. 2012 was one of the better years. I'm bummed that I didn't pull off any noteworthy hacks, but this year is looking good with KawaiiKart. I however did manage to sneak in a cool project, my GPU ray tracer. Sadly it doesn't yet use all four GPUs or photon map or <insert cool effect or optimization here>.

The coolest thing I did was actually in the way beginning of the year: I briefly drove a Porsche 911 Carrera GTS! It was quite an experience, from the euphoric engine roar to getting behind the wheel and driving it. I look forward to signing the lease in 2018...or 2019 if necessary.

Bayley and I managed to hit a practical wall in our arms race by going to quad socket platforms near the end of the year. (pictures will be coming soon -- these things are epic!) We're still waiting for various sales on Newegg and parts on Ebay, so they'll be done sometime before junior year ends.

Working out Recreational powerlifting three (or more) times a week worked quite well, even during hectic first term junior year. I don't know how I did it (maybe by throwing a class under a bus), but it worked quite well. I'm convinced it's one of the very few things that kept me sane this term. I really only did curls, sometimes bench presses and squats, but never deadlifts because I dislike doing them. I'm well aware that MIT has a powerlifting team, but I don't think I'll be joining them anytime soon due to lack of time. 

In any event, happy new year!

KawaiiKart Chassis Assembled!

Or part of. If I fail my finals, this would be the reason.

It only took about three hours to cut the 80/20 into their requisite lengths (while screwing up the lengths for the main chassis because I don't know how to use a ruler -__-) and screw them together. Hopefully I get more done after finals.

The Nicest Balls You Will Ever See

My CUDA Ray Tracer works! Now to make it photon map…

Back to Triple Displays

I nabbed two Dell Ultrasharp 2007s on ebay for $230 shipped. Unfortunately, the guy forgot to ship power and DVI cables; guess I'll be haggling the price down after finals week to compensate for the loss -_-. I also have to massage xmonad a bit to get display focusing and desktop switching just right.

Also I'm quite confident that I change setups as quickly as Bayley acquires new computers as a typical girl dumps her boyfriend. Not sure who I'm insulting =P.

Aaaaand before I forget, I'm posting my xorg.conf because I absolutely do not want to dig through the internet just to re-set up this configuration again.

# nvidia-settings: X configuration file generated by nvidia-settings
# nvidia-settings:  version 304.54  (buildmeister@swio-display-x86-rhel47-11)  Sat Sep 29 01:10:44 PDT 2012


Section "ServerLayout"

# Removed Option "Xinerama" "0"
    Identifier     "Layout0"
    Screen      0  "Screen0" 1200 0
    Screen      1  "Screen1" 3760 0
    Screen      2  "Screen2" 0 0
    InputDevice    "Keyboard0" "CoreKeyboard"
    InputDevice    "Mouse0" "CorePointer"
    Option         "Xinerama" "1"
EndSection

Section "Files"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Mouse0"
    Driver         "mouse"
    Option         "Protocol" "auto"
    Option         "Device" "/dev/psaux"
    Option         "Emulate3Buttons" "no"
    Option         "ZAxisMapping" "4 5"
EndSection

Section "InputDevice"

    # generated from default
    Identifier     "Keyboard0"
    Driver         "kbd"
EndSection

Section "Monitor"

    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor0"
    VendorName     "Unknown"
    ModelName      "DELL3007WFPHC"
    HorizSync       49.3 - 98.5
    VertRefresh     59.9 - 59.9
    Option         "DPMS"
EndSection

Section "Monitor"

    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor1"
    VendorName     "Unknown"
    ModelName      "DELL 2007FP"
    HorizSync       30.0 - 83.0
    VertRefresh     56.0 - 76.0
    Option         "DPMS"
EndSection

Section "Monitor"

    # HorizSync source: edid, VertRefresh source: edid
    Identifier     "Monitor2"
    VendorName     "Unknown"
    ModelName      "DELL 2007FP"
    HorizSync       30.0 - 83.0
    VertRefresh     56.0 - 76.0
    Option         "DPMS"
EndSection

Section "Device"
    Identifier     "Device0"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GTX 460"
    BusID          "PCI:19:0:0"
EndSection

Section "Device"
    Identifier     "Device1"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GTX 460"
    BusID          "PCI:18:0:0"
    Screen          0
EndSection

Section "Device"
    Identifier     "Device2"
    Driver         "nvidia"
    VendorName     "NVIDIA Corporation"
    BoardName      "GeForce GTX 460"
    BusID          "PCI:18:0:0"
    Screen          1
EndSection

Section "Screen"
    Identifier     "Screen0"
    Device         "Device0"
    Monitor        "Monitor0"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "metamodes" "nvidia-auto-select +0+0"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-0: nvidia-auto-select +0+0 { Rotation=left }"
    Identifier     "Screen1"
    Device         "Device1"
    Monitor        "Monitor1"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "metamodes" "DFP-0: nvidia-auto-select +0+0 { Rotation=left }"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Screen"

# Removed Option "metamodes" "DFP-1: nvidia-auto-select +0+0 { Rotation=left }"
    Identifier     "Screen2"
    Device         "Device2"
    Monitor        "Monitor2"
    DefaultDepth    24
    Option         "Stereo" "0"
    Option         "metamodes" "DFP-1: nvidia-auto-select +0+0 { Rotation=left }"
    SubSection     "Display"
        Depth       24
    EndSubSection
EndSection

Section "Extensions"
    Option         "Composite" "Disable"
EndSection