Rolls Report: Nov. 21 – Last Day of Rolls

This past weekend marked the end of rolls for the fall semester. Frosty nights and finals mean that buggies settle in for their winter naps and the elves come out to finish builds in time for the spring semester. Although the previous weekend saw every team out, far fewer were came out this weekend. On Sunday, only 4 teams committed to rolling and Sweepstakes canceled rolls.

In Attendance 

Org Saturday Sunday
AEPi
Apex  Ember, Phoenix
CIA  Impulse, Icarus, Ascension, Orca
Fringe
PhiDelt  Perun
PiKA  Banshee
SDC  Malice, Havoc, Addiction
SigEp  Kraken, Pandora
SigNu
Spirit  Inviscid, Zuke, Fuko, Seraph
Robo

Observations (Saturday Gallery) Continue reading

Mini Raceday Alumni Data Dump

As you probably already knew, this past weekend was the very exciting Mini Raceday Weekend. We posted the official Sweepstakes freeroll and backhill times, but thanks to the efforts of a couple of our more dedicated alumni, we have bonus data! Specifically we have the calculated speeds just before the chute and at the fourth window of Porter Hall.

The columns represent the speed of the buggy entering the chute (Chute), speed at the fourth window of Porter (Window 4), and whether or not the buggy needed to be pushed before the fourth Porter window.

Official BAA Times 

Team Roll Buggy Chute (mph) Window 4 (mph) Pushed
PhiDelt 1 Perun 25.6 11.9 P
PiKA 1 Banshee 35.9 17.1
PiKA 1 Raptor 27.7
SigEp 1 Kraken 30.3
AEPi 1 Kamikaze 27.1 9.7 P
Apex 1 Phoenix 22.7 9.7 P
CIA 1 Equinox 33.7 16.2
CIA 1 Icarus 31.6 13
CIA 1 Orca 29.8 9.1 P
CIA 1 Ascension 23.6 9 P
SDC 1 Malice 35.2 15.8
SDC 1 Vice 31
SDC 1 Havoc 30.5 9.8
Fringe 1 Bissa 34.1 13.4
Fringe 1 Beacon 12.5
Fringe 1 Balius 10.8 P
SigNu 1 Krait 30.7 11 P
Spirit 1 1 33.9 12.7 P
Spirit 1 2 28.3
PhiDelt 2 Perun 24.2
PiKA 2 Banshee 35 15.7
PiKA 2 Raptor 28.1
SigEp 2 Kraken 30.3 10 P
SigEp 2 Pandora 17
AEPi 2 Kamikaze 26.5 9.2 P
Apex 2 Ember 27.6 10.7 P
CIA 2 Equinox 31.1 11.6
CIA 2 Icarus 31.7 12.7
Orca 14
CIA 2 Ascension 23.8 8.1
CIA 2 Impulse 27.2 10.5 P
SDC 2 Malice 35.1 16.1
SDC 2 Vice 31.5 11.9
SDC 2 Havoc 30.4 10.9
Fringe 2 Bissa 33.6 13.7
Fringe 2 Beacon 33.7 12
Fringe 2 Baleus 28.9 9.3 P
Spirit 2 1 33.2 15 P
Spirit 2 2 30.9 11.1 P
Spirit 2 3 30.7
PhiDelt 3 Perun 24.5
PiKA 3 Banshee 35.2 17.1
SigEp 3 Kraken 27.2 7.2 P
AEPi 3 Kamikaze 26.9 8.6 P
Apex 3 Phoenix 30.5 11 P
CIA 3 Equinox 33.3 16.4
CIA 3 Icarus 30.4 11
CIA 3 Orca 28.4 9.6 P
SDC 3 Malice 34.8 15
SDC 3 Vice 32.8

 

The take home points are:

  • PiKA is the fastest downhill and back up
  • SDC is 2% slower than PiKA on the downhill, but 3rd fastest uphill
  • CIA is another 4-5% slower than PiKA on the downhill, but depending on the buggy are between SDC and PiKA going back up
  • CIA, Fringe, and Spirit have almost equal downhill speeds, but Fringe and Spirit are scrubbing speed in the chute.
  • Spirit’s down hill times would suggest a greater rollout than they are getting

 

Speeds were calculated by capturing video using a Nikon 1 series camera, all of which have the ability to take 640 x 240 movies at 1200 frames/sec. The cameras can only record 3 seconds at that speed, so the time it takes a buggy to pass between nearby landmarks (e.g. pairs of trees or parking spot lines) can be precisely measured. After some scouting, our intrepid alumni found useful spots on the course where every buggy takes more or less the same path. They placed the camera where every buggy could be filmed with the same perspective. Each frame is a normal 2D image, so objects in the background remain stationary. This allows you to open the movie in your video editing software of choice and note the time at which the nose of the buggy reaches each landmark. If the distance between the landmarks is known, the time can be converted to a speed.

For comparison, Sweepstakes uses the FinishLynx system on Raceday, which is typically set to take a 1000 x 1 image 1000 times/sec. The finish line software then assembles a series of these 1D lines into a distorted 2D image, where the horizontal axis is time. If you know the length of the buggy, you can tell when the nose and tail cross the finish line and convert that into a speed, however you can only observe one line. The system is optimized to calibrate its clock to real life and not vary much. This allows for accurate split times by placing a camera at each split point. The internal clocks used in consumer-quality cameras are not as accurate, so even though we used multiple cameras focused on different physical locations, we cannot correlate events in each well enough to get useful split times.

More work is needed in calibrating against either another measurement method or something of known speed before comparing speeds obtained our way with other sources, or, for that matter, with historic times. Regardless, comparing 2 teams on the same day should be safe – the systematic errors should affect everyone equally. The video files used to generate these times will be made available on cmubuggy.org for the viewing pleasure of all interested. 


This fabulous data is brought to you through the ideas and efforts of Shafeeq Sinnamohideen and Tom Wood.

 

Rolls Report: Nov. 14 & 15 – Mini Raceday!

This was a great weekend for buggy: fair weather, clean(er) roads, and Mini Raceday. If you are reading this post you are probably already familiar with the concept of Mini Raceday and all that it entails, but if you stumbled upon cmubuggy.org through a fluke of the internet, let us explain (because we wouldn’t want this to be the confusing post). Despite what the name implies, extra small buggies with Thumbelina-sized drivers did not zip around the course this weekend. What actually happened was that freeroll (crosswalk to Hill 3) and backhills runs were timed by Sweepstakes and others (Ed the Sweepstakes chair, Guochen ass’t chair, and Matteo a SDC mechanic). The organizations with the fastest men’s and women’s teams then receive bragging rights, congratulatory back slaps, and a fabulous mystery prize from Sweepstakes. This year the fastest freeroll went to PiKA, fastest men’s backhills to SDC, fastest women’s backhills to CIA, and fastest overall time to SDC. The prize has yet to be announced by Sweepstakes. Probably because they don’t know what it is yet. The times are summarized in a table at the bottom of the report. In the end, the point of Mini Raceday is to simply get an official gauge of where the teams stand at this point in the year. However a lot can happen in the spring semester.

Mini Raceday excitement aside, it was an all-around good weekend of rolls. Saturday 6 teams made it out; 7 if you count Robobuggy. We only had one stop on Saturday which was due to a flagging malfunction, and there were no other incidents. Sunday saw all 11 teams rolling, many with a large fleet. Obviously this was to get timing data on as many buggies/drivers as possible, but it did slow things down a bit. Sunday was a fairly clean day. One driver had a spin at the top of the freeroll, but both driver and buggy were uninjured. Also, one SDC driver had a slight issue with one chute turn, but came to a complete stop before any collisions.

In Attendance 

Org Saturday Sunday
AEPi  Kamikaze
Apex  Ember, Phoenix Ember, Phoenix
CIA  Impulse, Icarus, Ascension, Equinox Impulse, Orca, Icarus, Ascension, Equinox
Fringe  Balius, Bissa, Beacon Balius, Bissa, Beacon
PhiDelt Perun
PiKA  Banshee, Raptor Banshee, Raptor
SDC  Malice, Havoc Malice, Havoc, Avarice
SigEp  Kraken, Pandora Kraken, Barracuda, Pandora
SigNu Krait
Spirit  Inviscid, Zuke, Fuko Inviscid, Zuke, Seraph
Robo  Transistor Transistor

Observations (Saturday Gallery | Sunday Gallery) Continue reading

Rolls Report: Nov. 7 & 8 – Leaves and Speed

After 3 weeks of no or singular days of rolls, we finally had a glorious full weekend of rolls. 11 teams, several bicyclists, and a few joggers made their way around the course over Saturday and Sunday. While the latter two weren’t exactly welcome, they didn’t impede too much in the grand scheme of things. However, a couple of the bicycles made it to the chute flaggers before anyone noticed. Active flaggers are, of course, looking the other way, but perhaps the non-active flaggers should keep an eye out for unwanted visitors. More than course-intruders, an excessive amount of leaves near the chute turn caused a significant delay in the roll order on Saturday. The first four teams to roll must have had negative things to say, because after the fourth team there was an all-hands-on-deck effort to clear the leaves from the turn. For 30 minutes rakes, brooms, blowers, feet, and stop flags were used to free the road of leaves. Annoyance of the leaves aside, the teammate was great to see.

In Attendance 

Org Saturday Sunday
AEPi Kamikaze  Kamikaze
Apex  Ember Ember
CIA  Impulse, Orca, Icarus, Ascension, Equinox Impulse, Orca, Icarus, Ascension, Equinox
Fringe  Balius, Bissa, Beacon Balius, Bissa, Beacon
PhiDelt  Perun
PiKA  Banshee Banshee
SDC  Malice, Havoc, Vice Malice, Havoc, Vice, Avarice
SigEp Kraken, Pandora Kraken, Pandora
SigNu Krait
Spirit  Inviscid, Zuke, Fuko Inviscid, Zuke, Fuko, Seraph
Robo  Transistor Transistor

Observations (Saturday Gallery | Sunday Gallery) Continue reading

Rolls Report: Oct. 31 – Happy Halloween!

After last week’s hiatus thanks to midsemester break, buggies were out and rolling again this weekend. Well, they were rolling on Saturday. Apparently, most of the organizations didn’t want to do buggy things the day after Halloween. They must have been up late handing out candy to trick-or-treaters. This Saturday was also the last day before Daylight Savings, so teams only had 1 hour to get their buggies around the course. All-in-all it was a petite weekend of rolls.

Even if we only had one short day of buggies, it was still a pretty great day. We are happy to report there were no crashes or spins. There was one stop, but it was due to some hatch issues and was overall relatively minor. One of the most exciting things to happen was a visit from Sam Swift of BAA fame. It’s always good to have our alumni back for surprise appearances. Unfortunately no one manage to get a picture. Or an autograph. In lieu of a autographed picture of Sam, we present a picture of a bus that tried to come on the course. Apparently Sam was as amazed at the newly paved roads as the rest of us Pittsburgh folks were at the start of the semester.

Because of the singular short day of rolls, the individual write-ups are a little shorter than normal. We thought about just making stuff up, but didn’t want to tarnish the integrity of the BAA rolls report.

In Attendance 

Org Saturday Sunday
AEPi Kamikaze
Apex  Ember, Phoenix
CIA  Icarus, Orca, Ascension
Fringe  Balius, Bissa, Beacon
PhiDelt  Perun
PiKA  Banshee
SDC  Malice, Avarice, Havoc, Vice
SigEp
SigNu
Spirit  Inviscid, Zuke, Seraph, Fuko
Robo

Observations (Saturday Gallery)

  • AEPi – Usually we only see AEPi out on Sundays, but with the premediated lack of buggy activity for All Saints Day, Kamikaze was out rolling this Saturday. The AEPi driver was rolling with bags for the entire day. While we aren’t sure what they are trying to work on, the buggy is moving fairly slow for this point in the season.
  • Apex – Both Phoenix and Ember were rolling without bags this Saturday and making clear gains in their speeds. One observer noted that Apex’s chute lines are starting to take shape smooth out. Hopefully we’ll be seeing bigger and better rollouts in the future.
  • CIA – Equinox missed her first day of rolls this season. Rumors as to why range from a lack of driver availability to garage trolls. Given the day, it was probably trolls. CIA is still leading the way with their impressive rollouts even while other teams make improvements. As always, the CIA drivers are taking more daring chute lines much tighter than the other teams and are flirting with the manhole cover on a regular basis.
  • Fringe – Describing Fringe at rolls is becoming like a broken record: very smooth, very quick, very stable. Despite the dependable nature of their rolls, Fringe buggies just are not getting the rollouts we would expect from them. We anticipate seeing more from them come spring.
  • PhiDelt – PhiDelt rolled this Saturday with only one of their 3 drivers. Slowly but surely they are increasing in speed and are now getting rollouts past the hay bales and making it into Hill 3.
  • PiKA – Banshee was screaming around the course, catching up to CIA’s rollouts. They continue to drift through the chute turn, scrubbing quite a bit of speed. They will be giving the other orgs a run for their rollout money if they can nail down the chute turn.
  • SAE – We are excited to report that SAE were back in action this weekend, returning to the course for the second time this semester. They are rolling on some fancy wheels which look like they have a dynamic camber as Lucy rolls and leans through the chute.
  • SDC – Although we have never described SDC as slow this semester, the team is significantly ramping up their speed. Both Malice and Vice are turning hard at the chute flag resulting in some skidding/drifting action. Havoc provided perhaps the most excitement of the day when she came to a stop just after Hill 2 due to a hatch issue. While this caused a significant delay in the schedule, driver and buggy are believed to be fine.
  • Spirit – With Fuko making her debut appearance for the semester, Spirit was out in full force rolling a slightly different combination of 4 of their buggies. Fuko’s previous hibernation was made all the more apparent by her paint job from 3 racedays ago. The team is continuously picking up speed and had a clean and quick days of rolls.

There was some buzz along the sidelines this weekend when Sweepstakes called rolls at 8:40am instead of waiting until 9:00am. Perhaps the bike lane bollards take more time to reinstall after rolls? Regardless, the lost 20 minutes seem quite precious. If you made it all the way to the bottom of this article and know anything about the truncated time or have some thoughts on the subject in general, feel free to leave a comment.


Rolls Report Contributors:
Ben Matzke
Thomas Felmley