Questions and Answers about Combat Robotics from Team Run Amok.

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7340 Questions and Answers about Combat Robotics
from Team Run Amok

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Even small combat robots can be dangerous! Learn proper construction and safety techniques before attempting to build and operate a combat robot. Do not operate combat robots without proper safeguards.

A Portion of Torsion
Q: Remember that surprise I alluded to in my last post? Well… I made a Hexbug 'Run Amok' using a Hexbug fire ant, a 3D printer, card stock, some Lego pieces, and a whole lot of double sided tape. She will be fighting in my next HexBug series, Ultimate HexBug Tournament 2! Season one will release in early 2024, so expect to see her fight 'Tombstone', 'Disarray', and 'Spinning Mayhem' in summer/fall of next year (fight schedule subject to change based on multiple factors)!
My only question today is where can I find springs that look like the picture at left, or below, or wherever they show up on your email. The wire needs to be 24 gauge or less. I’ve looked at Lowe’s, Home Depot, and on Amazon, but I can only find those ‘slinky style’ springs, which are good for trampolines, not so good for HexBug flippers.

- Sincerely, Iceywave [West of San Antonio]

A: [Mark J.] I'm honored, Iceywave. That's as nice a micro 'Run Amok' as I've seen. Thanks for the photo!

You're looking for a "torsion spring". Using that name you can find a bewildering selection of sizes, lengths, and number of coils on Amazon, like these 0.5mm wire 6-coil springs.

If you can't find the exact spring you need, you can start with some steel music wire in the diameter you need and wrap it tightly around a small diameter rod to make your own custom spring. The first few you make will be... a learning experience, but you'll get the knack pretty quickly. Your local hobby shop almost certainly has music wire in stock. A 24 gauge wire is 0.022" in diameter, and 0.020" music wire is a standard size.

A Really Big Show
Q: According to ['Robotica' Producer] Don Weiner he said something about Robotica having autonomous robots and wanting it to become a full arena show where you have multiple games laid out I.e. flying robots and underwater robot battles if you watch 'Inside Robotica' Episode 306 on YouTube I wonder what he meant by that, what do you think? [Erskine, Scotland ☆]

A: [Mark J.] The Discovery Network was very excited by the TV ratings generated by the first season of Robotica -- it was the highest rated of all the robot shows. The budget for seasons two and three were increased considerably over season one, and I can assume they were exploring grander options for subsequent seasons. I think the 'Inside Robotica' comments were just ideas that were being tossed around, but the ratings for seasons two and three did not meet expectations so future options were not explored farther.

And Then Some
Q: I've been planning a 'Son of Whyachi' style beetleweight and am planning on using a super powerful motor such as a propdrive v2 5050 from hobbyking but was wondering is it too overkill for the weight class? [Social Media]

A: [Mark J.] The impact power of a spinner weapon comes from the kinetic energy stored in the rotating mass of the weapon rotor. That stored energy is MUCH greater than the instantaneous power available from the motor itself. A more powerful motor will spin a given weapon up to a given speed faster, but your weapon's speed is limited by decreasing weapon 'bite' and the mass allowance for the weapon rotor is decreased by the larger motor's increased mass. There is a "sweet spot" for motor size. Analysis of current successful spinner robots shows a trend toward weapon motors of a weight that falls along a logarithmic function of the robot's weight [chart above]. A typical successful beetleweight robot has a weapon motor that weighs about 6% of the robot's weight -- a PropDrive v2 5050 motor would make up about 25% of a beetleweight's weight. More information on this weight relationship is available here: Combat Robot Brushless Motor Selection.

The Time Keeper
Q: I like the Robotica Season 1 filming emphasis in the pits but who was the guy that said "and your 45 minutes starts now!" ? [Erskine, Scotland ☆]

A: [Mark J.] You've really strayed into Robotica minutia now, Erskine.

The Robotica rules allowed for 45 minutes of robot repair and modification time in the pit area between events. The time limit was there only to keep the filming on schedule. You may be able to spot small kitchen timers provided by the production on the pit tables. In practice the set changes required much more than forty-five minutes, so I do not recall the time limit actually being enforced.

Story Producer Andrew Greenberger was the primary contact between RBI Productions and the teams, but I recall Segment Producer Aaron Wiener being involved is some specific shots. If you can give me an episode number and a time mark I will try to figure out who made that announcement in the pits, but after more than twenty-two years I can't promise an accurate answer.

Keep it Snug
Q: How much slack is acceptable for a timing belt? I use a 22 tooth and 42 tooth gear from Fingertech for the 4mm wide belt. The center distance I designed is 60.85 mm, which gives me 2.7 mm of slack. Is that too much? [Cambridge, Massachusetts]

A: [Mark J.] FingerTech's recommendation is to keep slack on their S3M timing belts under 1mm:

"A perfectly tensioned belt will have no slack. If you have a set Center Distance you will probably have some slack (but not much thanks to our many belt sizes!). Under 1mm is good for a robot. Above starts getting sloppy so you will want a tensioner, or maybe go up in pulley size."
A 62mm center distance would give 0.5mm slack with a 74 tooth belt.
Turn it On and Wait
Q: My Malenki receiver/ESC is not connecting to my transmitter even though it has done it before. How do I fix this problem? [Social Media]

A: [Mark J.] The Malenki-Nano has an unusual method for entering 'bind mode' and can 'unbind' from your transmitter under some conditions.

To re-bind the Malenki-Nano to your transmitter:

  1. With your transmitter off and any weapons disabled, power on the Malenki.
  2. Wait for the blue LED on the Malenki to start flashing. This may take a couple minutes!
  3. Turn your transmitter on in 'bind mode' -- check your transmitter documentation.
  4. Wait for the blue LED on the Malenki to stop flashing. This should take only a few seconds.
  5. Power off the Malenki.
  6. Power off the transmitter.
In routine use it is good practice to turn your transmitter on before powering up your robot.
Heads or Tails
Q: I am looking for an r/c brushed motor controller that has a third channel to flip. I have a Sabertooth 2x32 ESC that does not have flip mode. I want the ability to hit a switch on the TX to make the rear of the robot become the front.

It would even be better if I could program my radio to do it. I currently use a Jumper T16 radio for the robot, but I also have Taranis Qx7 and Futaba 14sg transmitters. [Social Media]

A: [Mark J.] I don't know of any currently produced ESCs that feature an invert mode, but an invert switch is very easy to implement on OpenTX transmitters like your Jumper and Taranis. See the 'Simple Invert Switch' section of my Taranis Transmitter Combat Guide.

Alternately, the FingerTech tinyMixer plugs in between your receiver and ESC and has a third channel plug to provide an invert function. The tinyMixer does allow you to turn off the mixing function to allow you to use transmitter mixing while retaining its invert function.

NOTE: Many builders find the distraction of switching in and out of invert mode to be more trouble than it is worth. With practice, driving inverted can become natural and fluid. The choice is yours.

Don't Change a Thing!
Q: How would you feel if there was a director’s cut of Robotica Season 1 Episode 1 with Run Amok And Spring Breaker running the speedway and Maze First and Episode 2 with Kritical Mass And Grimlock running the gauntlet first then Boelter Beast and Hot Wheels following just to make the correct order of Red Team Vs Blue Team first THEN Silver Team Vs Gold Team? [Erskine, Scotland ☆] A: [Mark J.] The director already had his say. He told the video editors to put Robotica together just the way it is. If you start tampering with it...  I might not win!!! 
Ask Aaron's devoted reader 'Icyewave' has had unusual problems getting his FingerTech Viper combat kit operational. Iceywave's posts about the Viper were interspersed with entertaining inquiries on other topics. I've elected to assemble the Viper posts into a single block to allow Ask Aaron's readers to better follow the diagnosis process, and I've stripped out the other recent posts and grouped them at the end.
The Flamin’Yon File
Q: My Viper antweight is having drive problems. It’s the standard wedge kit with no altered components. In full-throttle forward the right SilverSpark turns but the left one doesn’t. Full-throttle left & right is the same issue, and it won’t move at all when it tries to go backwards. I’ve triple checked all the wires and connections and read the whole manual a dozen times, but I can’t figure out what is wrong. Should I keep trying to fix this one, or just order a new kit?

- Sincerely, a Hispanic nerd : )  [West of San Antonio]

A: [Mark J.] I don't think you have a robot problem -- I think your transmitter set-up is the issue. I'm a bit confused by your problem description, but I think you're describing this set of responses:

  • Forward - right motor spins.
  • Reverse - neither motor spins.
  •  Right   - left motor spins one way?
  •  Left   - left motor spins the other way?
  • If you ordered the FlySky T6A transmitter from FingerTech as an add-on to your kit it should have come pre-programmed with a correct channel mix. Email and explain your problem. FingerTech is very good at correcting their errors.
  • If you are using your own transmitter, tell me what it is and I'll try to walk you thru a correct channel mix.

Q: Hi Mark, sorry about not responding sooner. Very personal family stuff has prevented me from emailing FingerTech, but I want you to know how helpful you’ve been for me. Without your help, my dreams for Flamin'Yon would’ve been dashed, so THANK YOU!

A: [Mark J.] Family has to come first. Maybe it would help if I drafted an email to FingerTech for you?

Q: Hello Mark, thank you for your kind offer, but I’ll definitely be able to email FingerTech today! I noticed something else strange just now. The E.S.C. connected to the left motor sometimes makes noise and blinks green and red rapidly when I don’t move the stick. Could that be an indicator of something?

A: Yes, it could! The flashing red/green indicates that the ESC has gone into calibration mode. There is a known bug with a few of the v2.6 tinyESCs. From the FingerTech tinyESC page:

"We've tracked down and SQUASHED a bug that affected ~2% of v2.6 tinyESCs. It would sometimes cause the Calibration bits to get scrambled on powerup. We will replace any affected tinyESCs. If you have one with this issue, email us!"
Include the flashing light and noise with your other symptoms in your email to FingerTech. I still believe you may have a transmitter problem, but FingerTech may need to fix the ESC as well.

Q: Soooooooooooo… I have some embarrassing news, it wasn’t a transmitter problem, it was a battery problem! The day I got my antweight, I bought a 9V Eveready Gold from Walmart. Today I bought a 9V Duracell from the same Walmart, and now Flamin’Yon works like a dream! I guess I learned 3 things from this...

1. Sometimes, the solution to life’s problems is right in front of our faces but we dismiss it as “too obvious”

2. Don’t buy Eveready Gold 9 Volts

3. Mark Joeger will always be happy to help a fellow robot combat enthusiast : )

A: Dope Slap! I never asked about your battery! In my defense, your bot's symptoms don't fit the typical 'low battery' profile. A weak battery will usually perform fine on a test bench until motor load rises, the battery output voltage drops below the receiver minimum, and everything resets. I'll make a note that the Viper behaves differently. Still, a simple fix is a good fix -- congratulations!

FingerTech recommends the high-output Duracell "Procell" 9V Battery for the Viper, but apparently they don't supply one with the kit.

Comment: Thank you so much for all the kind words and info about combat robotics, I’ll put a Run Amok sticker on Flamin’Yon in your honor. - see you in a few weeks,(or when my surprise is ready, hehe) Iceywave.

How Bad Is It?
Q: Do you know the dimensions for the 33.3:1 SilverSparks? If I have to build a new one, I’ll probably 3D an entirely different chassis.

A: Your Viper kit has a pair of 33.3:1 SilverSpark motors, do you not have a way to measure them?

  • Gearbox Length: 12.7mm (0.50in)
  • Motor Length: 28.7mm (1.13in)
  • Gearbox Diameter: 16mm (0.63in)
  • Shaft Diameter: 3mm (0.12in) with flat along length
  • Shaft Length: 38mm (1.5in)
  • Mounting Holes (2): #2-56 spaced 11mm (0.433in) apart

Q: Hi Mark, sorry about not measuring my motors myself. I... I don’t know what went through my head but I clearly didn’t think I could measure it myself for some reason. Probably teenage anxiety.

P.S. - Is this hamburger bad?

- Sincerely, Iceywave.

A: I've seen worse -- but yes, it's bad. I give it four pickles on the bad hamburger scale.

Two Questions and One Observation
Q: It’s Iceywave again, back at ya with more questions.

1. Were there any independent flying combat robots other than SPS2? By "independent" I mean a robot that isn’t a counterpart to a main bot, (Warrior Clan, Subzero,etc.) it's an idea for a short YouTube video.

2. Are infrared controllers and receivers legal for combat robots? I would like to one day enter a heavily modified HexBug BattleBot in a fairyweight competition, but I don’t want to spend my time making one if I’m not allowed to compete.

This isn’t a question, but I noticed in the CRHoF under 2023 results, it lists Whiplash as an honorable mention, even though it already got honorable mention status in 2021.

Other than that, I want you to know how helpful you’ve been for me, I haven’t emailed FingerTech yet (very busy) but without your help, my dreams for Flamin'Yon would’ve been dashed, so THANK YOU!

- Sincerely, an amateur animator : )  [West of San Antonio]

A: [Mark J.] Thanks for spotting the misprint in the Combat Robot Hall of Fame results summary. Other places in the website correctly show 2023 honorable mention to Droopy Hydra Lynx SawBlaze and MegatRON and I have corrected the summary to show the same.

Happy to help with your robot transmitter problem. Let me know what FingerTech has to say. Flamin'Yon is a great pun/name.

1) J.D. Streett's 1995 US Robot Wars lighter-than-air competitor 'SPS #2' (pictured) was for a long time the only "solo" flying robot to compete as a combat robot. That status ended in June, 2023 when Logan Davis entered the NHRL beetleweight tournament with a flame-spitting drone called 'Spitfire'. It managed to win two matches! Spitfire video

2) The legality of an IR controlled fairyweight would be entirely at the discretion of the event organizer. Contact the EO for any events you might enter for their clearance and any special conditions.

Whipped Cream and Bandages
Q: I heard a rumor on social media, but I can’t figure out if it's true or not:
'Ultraviolet' entered in BattleBots 2016 and lost to 'SOW' and 'Hypershock'. Depressed, he made his way to the Missouri Arch and leapt off, only to land on a U-Haul truck heading for Afghanistan. He worked in a roller rink as a whipped cream vendor, until he saved enough money to become a platypus farmer. He met a nice woman named Mausoleum, and they moved into an orange house, which gets burned down on November 4th and gets rebuilt on Nov. 5th. They had four children together, a boy, a girl, a hermaphrodite, and a welding mask. The family is doing well now.
Is this rumor true?

A: I can neither confirm or deny the rumor, Iceywave. Others interested in the source of this rumor mashup may wish to read this post and this post in "Aaron's Greatest Hits".

Q: P.S. I noticed that you put a space in between my eyes and mouth on my smiley faces, have I been typing emoticons incorrectly this whole time?

 - Sincerely, Iceywave [Chicago maybe?]

A: Just my personal preference. I think a text emoji with a space displays better on a web page. ; ^ )

There are Always Rumors
Q: Why did Robotica get canceled? I’ve heard some sources say TLC axed it because of comparatively low ratings. But I’ve also heard sources say that it got into copyright trouble with BattleBots and Robot Wars. You’re definitely the most reliable source about this show, so which is it?

A: Fans are always looking for plausible reasons why their fave shows were canceled. The show was so good it couldn't have had poor ratings!

  • BattleBots was canceled in 2002 because Budweiser threatened to pull all their advertising from the Comedy Central network.
  • Robotica was canceled because of intellectual property infringement issues with the early seasons of Robot Wars.
  • Captain Kangaroo was canceled because ‎they discovered that Bob Keeshan was an actual kangaroo.
None of the above rumors are true.

What's the Ante?
Q: Entry level costs [Melbourne, Australia]

A: [Mark J.] First, find your local events and determine what weight classes are supported in their tournaments. Smaller classes are less expensive both to build and maintain but you need to build something with which you can compete.

Costs vary depending on what your fabrication skills and equipment allow you to make versus what you will purchase pre-made:

  • A capable and beginner-friendly R/C transmitter (like the FlySky FS-i6) and receiver may be purchased for about $60. You can find cheaper transmitters, but you will face frustration in setting-up and adjusting the radio to suit your robot and driving preferences. See my combat robot radio guide.
  • A complete (minus radio) beginner one-pound antweight kit (FingerTech Viper) that can be upgraded as your growing skills merit may be purchased for about $150 US ($200 Canadian). An upgrade to a rechargeable lithium battery and charger is about $55 US ($75 Canadian) but the kit runs well on a 9-volt alkaline battery. Don't buy their optional radio; the Viper performs well with the FS-i6 radio mentioned above.
  • A simple, competitive, and almost complete three-pound beetleweight kit (BotKit D2 Dozer) runs about $400 US. Adding the required motor controller ($45) a couple LiPo batteries ($25) and a functional lipo charger ($35) brings the price up to about $500 US, plus radio. The Dozer kit will perform well with the FlySky radio mentioned above.
  • You will need spare parts and tools to repair damage to your robot during a tournament: drive gearmotors, wheels, and battery at a minimum -- plus simple hand tools, tape, quick-set adhesive, and perhaps soldering gear.
There are more exotic kits available but they require assembly and operational skills not commonly found in entry level competitors. Start simple.
It Gets Kinda Tricky
Q: It’s Iceywave again, I wanted to say thank you for the kind response, I’ll make sure my 2025 ballot is much better. Now I do have some questions…
  1. I’ll be starting a YouTube channel soon, would you like me to promote this website on my channel?
  2. How many total weight classes are there in the history of robot combat (It’s an idea for a YouTube video I’ll probably post later this year)?
- Sincerely, a bird clock lover : )  [West of San Antonio]

A: [Mark J.] We all get carried away from time to time, Iceywave. Think nothing of it.

  1. I don't request links or promotions for any sites - I have my reasons - but you're free to feature 'Ask Aaron' if you find the site worthy.
  2. That gets a little tricky. Weight classes evolved over time. For example, the 1994 US Robot Wars had three weight class maximums:
    • Lightweight - 40 pounds
    • Middleweight - 70 pounds
    • Heavyweight - 100 pounds
    Two of those classes changed for the 1995 event and a fourth 'Super Lightwight' class was added with a 20 pound maximum. All four of those weight limits were increased for the 1996 event.
In current competition there are minor differences in classes of the same name when conducted in Europe and measured in round kilograms versus US events measured in round pounds. As best I can figure, the full-combat weight classes that have persisted for more than a couple of years are:

Weight ClassMax Weight
UK Fleaweight0.75 kg
US Fairyweight 0.15 kg
UK Antweight0.15 kg
US Antweight1 lb
Canada Kilobot1 kg
US Beetleweight3 lb / 1.4 kg
UK Beetleweight3.3 lb / 1.5 kg
Mantisweight6 lb
Hobbyweight12 lb
Dogeweight15 lb
Featherweight30 lb / 13.6 kg
US Lightweight60 lb / 27 kg
UK Lightweight66 lb / 30 kg
US Middleweight120 lb / 54.5 kg
UK Middleweight121 lb / 55 kg
US Heavyweight220 lb / 100 kg
UK Heavyweight242 lb / 110 kg
BattleBots Reboot250 lb
SuperHeavyweight340 lb
MechWars SuperHeavy390 lb

Down At the Corner Pub
Q: Juggerbot’s team captain Mike Morrow has the entire episodes of the 'Inside Robotica' series which are in queue at being digitised what words would you say to him if they were uploaded onto the internet archive along with the Robotica Series? [Erskine, Scotland ☆]

A: [Mark J.] Mike Morrow lives four blocks from Run Amok corporate headquarters. When he gives you the digitized videos I'll meet him at the corner pub and buy him a beer with your regards.

You Need to Add Something
Q: how do I connect power to my servo? [Vestal, New York]

A: [Mark J.] That depends on your servo, receiver, and battery, Vestal.

A standard servo operates in the 5 volt to 6 volt range and is designed to be powered from the receiver power buss. Its flat 3-wire cable plugs into your receiver, with the three wires providing it with voltage, ground, and a position signal from the receiver.

As covered in my answer to your previous question;

  • The LiPo battery connects to your Electronic Speed Controller (ESC);
  • The Battery Eliminator Circuit (BEC) in the ESC reduces the battery voltage to a level suitable for your receiver; and
  • The flat 3-wire cable from the ESC carries power to the receiver.
Plugging you servo into the receiver passes on the BEC power to your servo -- but there is a problem. The tiny BEC in your small ESC produces enough current to operate you receiver, but not enough to operate a servo. You will need a more powerful BEC. See this post in the Ants, Beetles, and Fairies archive for more details and a circuit diagram.

Some servos and receivers can operate from higher voltages and may be wired to bypass the BEC entirely and be powered directly from the battery. I happen to know that your receiver cannot operate at LiPo voltage, but maybe your servo can -- check the servo spec sheet. If the servo can handle your full battery voltage it may be wired to as shown in the diagram below.

Home Machinist Options
Q: AR500 and S7 weapons are all the rage, but AR will eat my little hobby mill for breakfast, and heat treating S7 requires more than a torch and a bucket of oil.

What are my 'next best' options that are easier to handle? This will be for insect class bots. [Social Media]

A: [Mark J.] It sounds like you want to machine a three-dimensional weapon such as a drum rather than a disk that you could simply order from a water-jet cutting service in the material of your choice.

  • Cheap and widely available 4130 'chromoly' steel is the home machinist's go-to substitute for exotic alloys. You can surface-harden chromoly using standard practices and when you're done you'll have a tough and hard weapon.
  • You might also consider machining an aluminum alloy spinner and insetting one or more water-jetted AR500 impactors in the fashion of the FingerTech drum pictured above.

BotRank Has Names
Q: I’m trying to come up with a unique name for my robot. Is there a website or database I can check to see if someone else is using a certain name? [San Mateo, California]

A: [Mark J.] BotRank maintains a database of names of all the robots from all the event results that are sent to them. Not all events report their tournament results to BotRank, but it's the best single source of names available.

BotRank Unique Name DataBase

NOTE: BotRank's ranking and tournament records databases have been scrambled for about nine months now -- ignore them. The names data appears to be intact.

Mistakes Were Made
Q: Hey Mark, It’s Iceywave here, I wanted to apologize for my CRHoF ballot... [West of San Antonio]

A: [Mark J.] No apology required, Iceywave. Things went a little sideways with the 2023 Combat Robot Hall of Fame balloting, and more than a few people submitted very large numbers of robots on their ballots. No harm was done. I'm already able to look back at the matter and have a good laugh.

Your ballot did set a record, and that record will stand. Future balloting will have a limit on the number of robots listed.

Deep Cuts
Q: I found an episode of inside Robotica! Inside Robotica Episode 306 [Erskine, Scotland ☆]

A: [Mark J.] Good find, Erskine.

"Inside Robotica" was a weekly program broadcast on The Science Channel as sort of an 'after-show' for "Robotica" seasons 2 and 3 that aired on sister channel TLC. It was comprised of interviews with the teams, clips from the show, visits to the pits, and testing/construction video from the teams. It's pretty 'deep cut' stuff. I know of no other episodes that have survived.

It's Small and Light but...
Q: Hello,
I have a question involving powering my receiver and BEC's. I am swapping to a brushless drive from a previously brushed DESC-based system with a BEC built in (scorpion nano), but neither of my brushless ESC's (drive or weapon) have a BEC built in. Would it be a bad idea to just plug in my old brushed DESC to an unused port on my receiver to use as a BEC with my new brushless system? it seems to be lighter than most available BEC's ive seen online and I have space open in my chassis.

Thanks! [Redmond, Washington]

A: [Mark J.] Your Scorpion Nano is light and small, but according to the manufacturer's website the output from the BEC is both weak and a non-standard voltage:

The Scorpion Nano has a receiver battery eliminator circuit (BEC) that... can provide up to 100 mA of current at 3.3V to the RC receiver and other attached electronic circuits.
  • If your receiver has telemetry that sends information back to the transmitter (e.g. FS-iA6B) it will most likely require more than 100 mA of current; and
  • Most receivers require an operating voltage above 4.0 volts -- a typical BEC will output 5 or 6 volts.
Something like the FingerTech 5V 4A Switching UBEC Regulator is inexpensive, weighs about the same as your DESC, has a 6 to 23 volt input range, has a standard 5 volt output, and provides ample current to simultaneously run a telemetry receiver and a lifter servo. I'd grab a stand-alone BEC and never worry about adequate receiver current and voltage.

Nobody's Home
Q: Do all the BattleBots teams live in Las Vegas now so they can drive their robots in the daily destruct-a-thon? How much are they being paid? [Fort Colins, Colorado]

A: [Mark J.] The actual BattleBots teams are quite rarely involved in the BattleBots: Destruct-A-Thon shows. The 'famous' robots appearing in the live show are special easy-to-repair 'showbots' made to look like the real 'bots. These showbots all driven by the same two hired operators, and the "teams" that enter with the robots are actors. It's a show, not a competition.

The only real teams and robots in the show are there for the 'Proving Grounds' fights for new competitors. These fights are occasionally scheduled as part of a Destruct-A-Thon show. See these two consecutive archived posts for more information on the Las Vegas live shows.

As Many As You Like
Q: If I bind my Flysky T6a transmitter to a new receiver for a second robot will I lose my settings and single stick mixing? Will the settings come back if I re-bind the transmitter to the original receiver? [Las Vegas, Nevada]

A: [Mark J.] The transmitter is not bound to a receiver, it is the receiver that is bound to a transmitter. The binding process simply instructs the receiver to respond only to signals from a specific transmitter. Binding does not effect transmitter settings, but may effect receiver failsafe settings.

A receiver can only be bound to one transmitter at a time, but you can have any number of receivers simultaneously bound to the same transmitter. Binding a new receiver to a transmitter does not effect the ability of the transmitter to communicate with the original receiver.

Turn Signals Optional
Q: NO POWER WHEN TURNING LEFT AND RIGHT [Johannesburg, South Africa]


I take the problem statement above to mean that the robot does not respond to rotation commands from the transmitter, but perhaps the robot is a tracked or 4-wheel robot that has physical trouble when turning. In either case, I need to know a great deal more about the electronic components, the design of the robot, and the symptoms in order to provide useful suggestions to eliminate the problem. The hamburger is bad.

It Doesn't Go There
Q: how do I connect my zeee 11.1 volt lipo to the fs-i6 reciever? when i unplugged the small white plug from the reciever there was a spark and the reciever started smoking. [Vestal, New York]

A: [Mark J.] Your LiPo battery does not connect to the receiver, Vestal. Your FlySky receiver has an operating range of 4.5 to 6 volts, which is typical.

The red/black two-wire connector from your Zeee LiPo battery connects to the drive motor ESC (and the weapon ESC, if present). You may need to replace the ESC connector if it does not match. A special Battery Eliminator Circuit (BEC) in the ESC reduces the LiPo voltage to 5 volts and sends that power to the receiver thru the ESC's three-wire cable. I gave you the wiring diagram below in response to one of your earlier questions. The LiPo white 4-wire battery balance connector is not used for power output -- it is used only for battery charging. I'm not entirely sure what you plugged into what, but smoke from the receiver is a very bad sign. I suspect the receiver is toast.

Flip to Lift
Q: Can you point me in the right direction of using a toggle switch on the Flysky i6x to tell a servo to go to a specified position? I am building my first antweight lifter. I just want to be able to engage and disengage the lifter with a flick of a switch. [Social Media]

A: [Mark J.] It's not difficult:

  • Most versions of the FS-i6 transmitter firmware default to assigning radio channels 5 and 6 to variable knobs VrA and VrB, but the Aux Channels function of your transmitter can re-assign radio channels 5 and 6 to any of the four transmitter switches (SWA, SWB, SWC, SWD).
  • The End Points function sets the range of response of a device plugged into a specific receiver output. Move the switch you've assigned to the lifter servo channel to the position you wish to set, then dial in the servo position you want.
See the "Aux Channels" and "End Points" sections of our Programming the FlySky FS-i6 Transmitter for Combat Robotics Guide for details.
March, 2003 - Team Run Amok started 'Ask Aaron' to answer the robot combat questions sent to our team. Twenty years and 7200 questions later we're still fielding a very broad range of practical, theoretical, arcane, obscure, and sometimes just plain silly questions.

March, 2023 - We celebrated our 20th anniversary by giving away a stack of complete termite-weight robot kits in our 'Secret Identity Contest'. The contest is now closed, but you can still try to solve the puzzle. Think you know your combat robots? Give our anniversary puzzle a try:

Ask Aaron 20th Anniversary Contest Wrap-Up
They Don't Get It
Q: What do your combat robots think of the current COVID-19 pandemic? [Kansas City, Missouri]

A: [Mark J.] My robots don't care. My robots don't spread, suffer from, or die from Covid-19 -- but you can. Don't be selfish. Follow the science. Stay safe.

Two photos of Aaron Joerger Remembering Aaron Joerger, 1991 - 2013

The 'Ask Aaron' project was important to Aaron, and I continue the site in his memory. Thank you for the many kind messages of sympathy and support that have found their way to me. Aaron's obituary

- Mark Joerger   
Killer Robot drawing by Garrett Shikuma

Q: how can robots help us deal better with hurricanes and why? [Ontario, California]

A: [Aaron] Few people in Nebraska are threatened by hurricanes, so send a swarm of killer robots into low Atlantic and gulf coastal areas to drive the puny human inhabitants toward Nebraska. Problem solved.

Robot haiku:

That's obviously
A question from your homework.
Do your own research.

Aaron's Greatest Hits! More of Aaron's Poems Aaron at Nickelodeon Robot Wars Aaron's Minecraft High Dive Video Aaron's World of Warcraft Player Guide

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Why is there a 'Cheerleader' button?

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