After three years of development, DARPA Subterranean (SubT) Challenge teams will
get the chance to compete in the Final Event being held at the Louisville
Mega Cavern in Louisville, Kentucky on September 21-23, 2021.
All teams have to re-qualify for both System and Virtual competition.
Is Robotika Team going to be one of the 15 System teams and
10 Virtual teams? Update: 3/10/2021 —
8x 1hour Finals Videos
12th February 2021 — Final Event rules and schedule
DARPA announced on Wednesday 10th the rules for the final event, see
Final Event Competition Rules (pdf).
All teams have to qualify and the requirements are stronger, so see also new
Qualification Guilde (pdf).
Note, that there is not much time left — The Systems Competition qualification deadline is
April 21, 2021 and the Virtual Competition qualification deadline is June 29, 2021.
So what is new? The robots have to be able to recognize 10 types of artifacts: 3 common (Survivor,
Backpack, Phone), from tunnel (Fire Extinguisher, Drill), from urban (Gas, Vent) and from cave
(Rope, Helmet). Moreover there will be 10th, so far unknown, artifact type.
In order to qualify at least one robot has to demonstrate autonomous detection of
all types of artifacts!
For the System there will be two Preliminary Rounds, each 30 minutes long.
There will be 20 artifacts but teams will have only 25 reports. Only six best
teams will compete in the finals. There the limit is going to be 60 minutes
and number of artifact 40 with 45 allowed report attempts.
The Final Event of the Virtual Competition will consist of a Preliminary Round
and a Prize Round each with a separate solution submission window. The submissions
to the Preliminary Round will be evaluated and the results are expected to be
announced the week of August 9-13, 2021. The top 10 teams from the Preliminary
Round will be invited to submit solutions to the Prize Round to compete
for monetary prizes. The results and winners of the Prize Round will be
announced at the Final Event being held September 21-23, 2021.
4th March 2021 — Virtual qualification world released
Last night was released the Finals Qualification World for virtual SubT. In
Czech I would call it „kočkopes” as it combines tunnel, urban and cave into
one world. Simply from the very first crossing you can go to Urban to the
left, or to Cave to the right, or straight to Tunnel:
The qualification task is easy — just correctly report at least one
artifact. But is is hard, or it at least seems to be. The robots did not move
at all in the first two attempts due to a small bug
(#807, fixed). But the score is
still 00 …
Two Freyja robots were capable to follow the world boundary in 15 minutes
(simulated, it took almost 3 hours on CloudSim) but they both met under the
hill and start talking how it would be great to have some snow and ski … no
that was another story.
p.s. after another fix on OSRF side
(#809, it looks like the base was not
covered by signal) Robotika scored the first point and is
the first qualified team to Virtual
I guess that by Friday this will be official but I am really curious how they want to
force the System teams to detect it — well, they can force it but how to handle it?
So I am looking forward for official info!
25th March 2021 — Finals Practice Worlds
OK, The Cube
was really officially announced on Friday but I somehow overlooked it (as usual).
So now there is a new CloudSim release not only with
the 10th artifact but also the leaderboard
contains Finals Practice 1, 2, 3 worlds.
Yes, you can see team robotika now, sometimes leading with zeros.
But on the other hand the worlds were a little bit disappointing — they reflect
old circuits: tunnel, urban and cave.
If you are curious what LIDAR sees in the fog then the answer is simple — nothing.
Both Freyja as X4 drone turned around and returned.
3rd April — Virtual Fog
I must admit that the new feature fog emitter is a lot of fun. Camera does not see anything
except white image, lidar readings are random and there are no sonars available on the virtual robots.
A little bit promising are data from depth camera:
so now I am running simulation with suggested filter. We will see if robot Freya will
navigate through fog dense so much you could cut it (Rakosníček) and discover
drill artefact and score at lease one point in Finals Practice World 1. It
is nice that this trap is very close to the start (follow the right wall for 1 minute),
and it probably worked … unfortunately you cannot see fog in web-view.
It just scored the point, so no longer
leading with zero points in Finals Practice 1!
Here is the video of Freyja in fog in the Finals Qualification world …
or, if you want, you can watch it from the beginning. How many artifacts you
have you discovered? Backpack in Urban? What about the helmet in Cave?? No? Well, check the fog again.
Yeah, you can see meeting of two robots which caused switch to alternative route … and a little bit of
looping. The exploration was limited to 15 minutes (A900L) and then the robot returned to base.
Yes, we were also surprised that only eight teams (instead of fifteen) made it
to the Finals. On the other hand it is the elite (yeah, except us … but
you never know. This is surely related to the pandemic + if everything can be
canceled and the chance to win $2M is low …
One point is enough to qualify … if you check both lists you will see that
this time at least 4 teams will compete in both categories!
16th June 2021 — Kloubák and Skiddy in Cave Výpustek
Last weekend we had our first Robotika STIX (SubT/System Test Integration
Exercise) for SubT System Finals. And it was a very nice change after
almost a year (in some sense even more = since we returned from Urban Circuits)
of virtual live only.
The meeting place was cave
Moravia Karst with other famous caves
like Macocha and Býčí Skála nearby. Cave Výpustek was formerly used as a
hidden factory during war and later as a nuclear shelter. The main space is
relatively easy for our robots because the original natural cave was modified
to serve humans: the floor has hard flat concrete, lights are built in the
walls and are used for tourists excursions, and the ceiling is high enough so
you can walk around without a helmet. The most difficult elements were small
chain guardrails saying "do not enter", which was not correctly interpreted by
The software integration was difficult as expected. Since the last year, when
System Cave Circuit was canceled, the focus was Virtual competition only and
some hardware dependent pieces were no longer supported (or at least definitely
not retested on real hardware). In time the basic operating system shifted
forward to newer versions and the device drivers (RealSense tracking and depth
cameras) too. Yes and it also took a while to remember all the "minor details"
necessary to have everything smoothly running. But at the end both robots
Kloubak K2 and Skiddy moved and autonomously navigated and explored the cave
— the primary goal was reached. Note, that we were still rather recovering
the old strategy from last year Urban Circuit than the latest algorithms from
Virtual world (mainly terrain traversability and octomap mapping and
exploration). This is going to be our next step.
Skiddy — this is our newest robot built by Pavel Skotak. It is a relatively
small (0.4m x 0.56m x 0.35m) robot capable of entering narrow spaces. It is not
the lightest (18kg) because it is based on four hoverboard motors (BLDC motors
built in the wheels) which each weighs ~3kg. The robot was still "too fresh",
not all sensors were mounted (so far front RGBD and tracking camera only, the
rear depth camera was not integrated yet). Never-the-less robot was driving
around, demonstrating its driving capabilities and also the weak points
(connectors). The STIX was very important for the whole team to align and see
the complete status first hand.
p.s. There were a couple visitors including MartinL — and now there is a
slight chance that Skiddy won't be the last robot in the list for Platform
Qualification which ends on 21st June 2021 (5days).
If you thing that subterranean robotics is only about robots, broken wheels,
fried motor controllers and loose connectors then you are wrong. It is also
about logistics, team coordination, catering etc. The last night was a
perfect example. We were at the university testing communication between
Jetson Nano modules with the main control computer, finished at 9pm, bought
some groceries before the shop closed at 10pm and then drove "highway" D1 to
Brno and cave Býčí skála. We arrived at 1am the next day and surely several
people from CTU-CRAS-NORLAB team were still discussing ROS topics by the fire.
SubT is also about exciting (not necessarily positive) experiences. That
come about 30 minutes after we arrived and evaluated options where to sleep.
The best option (I would vote for it again!) was large open cave on tourist
hike, about 300 meters away. Shortly after we entered (and probably woke up
several competitors) the storm started to be much closer. It was fun, we could
see the walls from "the large windows" with each lightning … but then very
heavy rain started, which looked also OK, until I realized that I sleep in a
stream bed. It was the beginning so still OK, moved to higher dry place. But
then, about 15 minutes later opened waterfall directly on my sleeping bag.
"Fun." These are experiences you will never get sitting behind computer at home
and playing SubT Virtual track. (I can easily imagine Bilbo saying "we do
not want any adventure here").
The cave is very nice - large, spacious, a great playground for all kinds of
robots. Outside was temperature around 28C degrees and inside 8C degrees, so
the very first „surprise” we have seen was LIDAR blindness, again:
29th June 2021 — Team Robotika qualified for the Virtual Competition
We just received mail:
Team Robotika, Congratulations! After careful review of your submission, we
are pleased to inform you that you are now qualified to compete in the Final
Event of the SubT Challenge Virtual Competition.
The Subterranean (SubT) Challenge Team would like to congratulate you on placing in the top 10 of the Preliminary Round and advancing to the Prize Round of the Virtual Competition in the SubT Challenge Final Event!
With your team advancing, we would like to extend a friendly reminder that Prize Round submissions for the Final Event are due August 26th, 2021.
Please see a further reminder of dates of importance to keep in mind for the SubT Challenge Final Event:
Prize Round submissions are due August 26th
SubT Challenge Final Event will be broadcasted September 21st-24th on SubTv
The Awards Ceremony will be held on September 24th, where the winners of both the Systems and Virtual Competition will be announced
We will be following up in the coming days with an email providing further logistics regarding in-person attendance at the Final Event for you and your team. We look forward to seeing your Prize Round submissions!
That is a question! Shakespeare would probably use different letter like 2B or not 2B? …
You can tell that my mind is kind of broken after recent (and still running) SubT Virtual coding/testing
marathon. Today is the Virtual D-Day, i.e. in 5 hours (not sure if I will finish this text any soon)
26 AUG - Prize Round Submission Deadline. It is AoE (Anywhere on Earth)
which means 2pm CET time. And that should be noted even this blog is so silent this year …
Stress test, nice, I like that comes to my mind quite often, recently.
It is phrase Camryn used in Cave Circuit (actually around 1year ago). If you forgot who she is then here is
refreshing picture from the video:
Believe it or not, Robotika team is now in Louisville, KY, United States.
It was not straightforward as all travel from EU to USA is prohibited.
You have to ask for an exception (NIE - National Interest Exception), which
you may or may not get. We got DARPA invitation letter, which surely helped. Nevertheless confirmation that we could
go we received on Aug 18th less then a month ago (We are pleased to notify you that a national interest waiver to Presidential Proclamation
10143 has been approved for your travel to the United States. ... Please note that an approval of a national interest exception
does not guarantee entry into the United States. Yeap. Plane tickets, accomodation, car rental, robots, batteries, …
no time for relax.
Who will fly over the Atlantic? Which robot we should take? What SW we should run on it? These questions
were the most pressing while we were still finishing Virtual Finals. The member list self-reduced to 5 people from
Czech Republic (Jakub, Standa, TomasP, MartinS and me) and Frantisek flying over from Maryland.
Most of the robots we left at home. Promising are Kloubak K2 and new Skiddy. We dropped even
Maria living in U.S. as Frantisek is going to NASA Space Robotics Challenge
awards next week (the day after DARPA SubT) and there is nobody who could take care of her.
Thanks to Beda from CTU CRAS NORLAB team we have new 56V driver (replacement for fried(?) 24V version),
but are the firmware versions above the same? What unreleased means? And what exactly is this version?
Currious? It was 0.5.2!!! The configuration and API changed between these two versions which means more
OTOH there were also some good news — we passed E-stop check qualification and also the network test
on staging area worked fine. We have also see the entrance for the robots. Deadly — steep curved turn left, so it
will be the very first tests if robots are properly braking! BTW the mapping server worked too. The only
detail was that when we were testing it with docker mapping server we could not see anything, because there
was only one testing point. Even the corridor map from logfile was recognized by DARPA people, but we have
not seen it …
What else? We defined internal "rule" how to select the one unlucky(?) person, who will stay in the garage.
There are only 1+4 people alloweed in staging area and we are 6.
21th September 2021 — Robotika scores first point
Today (or better to say yesterday, it is 3am here now) we went through the first preliminary round. It was
hard from the very beginning (as expected) as behind the gate is already steep (about 20 degrees) downhill
slope terminated with sharp turn left. That is all you can see from the staging area. Surely enough also
the WiFi signal even for strong directed antenae ends on the crossing just behind the turn. Unfortunately
it holds also for LoRa (long range radio) device we use.
We are not allowed to publish any pictures from the internal course yet. The official recapitulation of
the day will be broadcasted today (22nd September 2021) on DARPA SubTv:
(so I will put pictures here say in 24 hours once this official part is over … just for you to have an
idea what to expect underground)
Kloubak K2 definitely did not want to go downhill (six times?). The good news was that although K2 did not like the
slope (maybe also the transformations in the map?) it always returned back to the staging area so that we could
try again. The robot may easily block the whole passage and no other robot (in our case only one — Skiddy)
could pass it. After tweaking some parameters we "push" it down, it managed to navigate narrow spaces and
picked urban entrance … it was funny to see crossing similar to
Virtual Qualification … yes this
sentence is maybe already leak, but it will be surely revealed soon and all teams already have seen it.
Skiddy remained at home — we wanted at least one robot to survive. More over Skiddy has broken rear right
In : dump_errors(odrv0)
system: no error
axis: no error
sensorless_estimator: no error
controller: no error
axis: no error
motor: no error
sensorless_estimator: no error
encoder: no error
controller: no error
… we suppose HW issues on wheel/cables/hall sensors … and hopefully it will be fixed today (the components were
delayed by one day :(.
And how far K2 managed to go? It died in 9 minutes of 16 remaining (the preliminary rounds are only 30 minutes long, or
short, and most of the time we spend convincing our robot to really go there):
… Jirka already pointed out yesterday, that I should not share these cryptic messages even within the team but …
maybe somebody will like the puzzle too . In other words there are about 18bytes missing in the stream which then
causes wrong parsing of CAN messages, triggering parsing asserts and terminating.
As side effect we reviewed that messages 0x11, 0x12, 0x13 and 0x14 release the wheels and for command desired_speed = (0, 0)
it actually releases the wheels! It is nice for transition of moving states but for flip() (K2 and Skiddy are symmetrical
so you can virtually flip front and rear instead of turn 180 degrees) with 2 seconds(?) wait in steep downhill it is deadly.
Other detail is to fix reporting of Z-coordinate, which was not that important for us in Urban and Tunnel as the place was
on one level (if we did not go up/down stairs or fly). Yeah, a lot of fun.
Today (22nd Sept) should be more or less copy of yesterday and tomorrow (23rd, Finals Prize Round) too as we will
probably start from the last place (no big deal). Note, that results of other teams are not secret but they are also not
official yet. One colleague went and ask most of the teams, so Explorer, CoSTAR and Cerberus all have 7 points,
CRAS CTU NORLAB 5 points, Coordinated Robotics 2 points and Robotika 1 point. If you want to see pictures and some details
about all competitors have a look at:
It is over now. At least for Robotika. We started at early morning at 6:30am, E-stop check, move to the stage.
There was basically no time to test the last HW/SW changes. Yesterday even encoders on K2 stopped working —
the CAN module got lose probably as Kloubak tried to overcome some of the obstacles. Yes, we also fried couple of
fuses. It started with 20A, then 30A and for the finals TomasP and MartinS changed it to 50A.
Skiddy got overnight new board filtering signals from the Hall sensors. It seemed to work OK in the morning (4am).
These were all good news .
The run was similar to preliminary rounds — there was an artifact on the junction (Jakub would got the lottery
prize, because he guess it in advance correctly). Nice surprise was view to Cave where was another artifact.
… maybe we should stop here and go home. Actually Kloubak did and showed up in the staging area again.
For the next attempt we just re-run it, K2 properly picked left way to the Urban area, nicely navigated in the coridor
to the left where we have never been before. Suprisingly it was available on LoRa all the time — not sure what
changed for the finals.
Now we are in the „jail” = Sequester area, that we would not be able to share with anybody the secrest we discovered
in the cave. On the other hand information worth $2M … I understand them … we just do not have it .
DARPA published all recordings of all 8 teams (1 hour competition time + few minutes of preparation). You can see there many
details which were not in the official presentation. Unfortunately there is always selection of one camera and in case there
are 5 and more active robots you miss something … but still something to do for long winter nights.