ArduBee – A micro drone for open source development | Hacker News Reader

ArduBee – A micro drone for open source development

discuss.ardupilot.org

371 pointsdieantwoord76 comments

Looks cool, it's great to have another good open source ready-to-fly option.

I have some concerns about larger PCB quadcopter designs because I can imagine that fatigue due to flexing on the PCB over long-term use could cause issues with the PCB delaminating or solder joints failing. On the ArduBee particularly, you can see a lot of surface-mount components mounted on the arms. I'd love to read more about any lifetime testing they've done on the PCB.

Of course there's always the risk of just crashing your drone and breaking it, but that's no different than other drone designs!

Why would the PCB flex? A quadcopter doesn't have that much of a twisting force being applied to it, no?

Vibration can be a concern with quadcopters especially if the motors and propellers are not properly balanced

I guess that's true, and they are using brushless motors so you have quite a bit of power there. Hmm.

Till 1 year ago it has been a great concern, especially for small drone. Now thanks to andyp1per, new Ardupilot dev, we have amazing results with dynamic filtering gyroscope noise, we could even track the mechanical noise peak based on actual RPM or live FFT.

Harmonic Notch Filter in Ardupilot https://ardupilot.org/copter/docs/common-imu-notch-filtering...

new and ongoing development

https://github.com/ArduPilot/ardupilot/pull/13121

https://github.com/ArduPilot/ardupilot/pull/14010

This was about mechanical strain from vibration.

You have to consider under the selected IMU, in the center, there is the most of the mass, made by the single 18650 Li-Ion battery. This solution is working, ArduBee is already flying good with the low pass filter in the gyro sets at 110Hz, if vibration would be an issue I guess it cannot fly

https://discuss.ardupilot.org/t/ardubee-a-ready-to-fly-micro...

Again, this issue is not the IMU, it's the whole thing breaking mechanically.

Fr4 material is basically fiberglass, and at 1.6mm thick it doesn't take much to bend it if it isn't supported. I think the weight of the motors could be an issue.

When resting, possibly. In flight, the weight of the battery would probably be the bigger concern, though I think you can get 2mm PCBs.

Thanks! this could be a great idea,the 2mm PCB could be an interesting option! We are devoted to 1.6mm PCB since the 5" version that weighs 220g and we haven't had any broken or issue on the PCB piece. The battery is well attached, fixed in 6 well distributed points on the PCB and aligned perfectly in the center of the 4 motors.

That's great then, if it works for you that's all that matters. I'm glad you guys are doing this.

While flying, the whole thing is suspended by the motors. It'd only be the weight of the centre components (mostly battery) that'd be flexing the arms.

(While crashing, all bets are off. But way back when I used to fly RC gliders they had a saying "If you build them to crash, they won't fly well. If you build them to fly well, they won't crash.")

Also, it's not like anyone expects thousands of hours of flight worthiness out of a consumer or even semi-pro drone. Sure the military might spec that for their Predator replacement, but most drone hobbyists I know end up with a bunch of perfectly serviceable old drones which they no longer fly because their gear became obsolete well before the mechanics failed irrepariably.

It flexes in flight (under power load, especially with a battery). The BeagleBone quadcopter we built with plexiglass flexed noticeably. FR4 is better, but it still will flex.

I don't really concern PCB drones to be long-term type drones. I have a few, and they're not too bad, as long as you don't fly them full speed at a wall.

Another? There is one already? Can you please provide info about it?

https://www.bitcraze.io/products/crazyflie-2-1/

I agree bitcraze its a great nano drone, but the first version has 3 minutes flight time and it can not be used outdoor, furthermore, Ardupilot is far more advanced and offers a lot more potential and with a huge community of experts, developers and user

UWB is really impressive and I see you have a optical flow positioning add-on board as well. Would like to play around with the current state-of-the-art, curious is fetting things to position indoors got easyer in the last 4 years, since last time I played with it.

Something I was thinking recently is using a lighthouse positioning system from Valve for indoor positioning. They have permissive licensing terms and the tech looks very promising:

https://partner.steamgames.com/vrlicensing

Yes! Lighthouse positioning system from Valve for indoor positioning it's so interesting, swarm compatible, easier to setup, cheaper and higher precision!

UWB is our present solution, its already easily in the 10cm accuracy in LOS scenario, it also enables complex indoor space with different connected rooms you want to cover, and you could cover easily 30m between each beacons.

We are discussing the option to integrate the optical flow directly into the ArduBee base. If you have suggestions, your contribution is highly appreciated.

There are also skyrocket drone, lastest serie is also running ArduPilot and most of the code is open both for autopilot and radio system

The next step up for rigidity is usually low-cost carbon fiber.

True, carbon fiber composites nearly always have greater stiffness and ultimate strength vs fiberglass

However, carbon fiber is also electrically conductive, vs fiberglass which is insulating, so that might be just a bit of a problem for a circuit board base... (perhaps solvable, but not the usual near-drop-in upgrade)

Yes carbon fiber its an amazing material for lightness and robustness, but we cannot see a way to innovate there with the usual separate parts and its needed cables. ArduBee its without a single wire, ready to fly, apart the motors wires. This in particular for micro drone is really a weakness in terms of flight time and aerodynamics.

We use the same design in the big brother for 5" propellers and double the weight of ArduBee. We make this development for our main focus about performative drone for swarm choreographies, its 2 years working with the fleet testing everyday to improve the quality of the performance. We had a lot of crashed indoor, and the pcb never had serious harm. We do not race obviously or high speed onto the wall!

That's great to hear that you haven't seen any issues with the PCB design. Thanks for all the great work!

Super cool!

Back in 2014 as a senior project in college we built a quadcopter for the BeagleBone: https://github.com/Rose-Hulman-ROBO4xx/1314-BeagleBone-Quadc...

We considered building the entire thing as a PCB, but it was pretty expensive to build one that size, plus we had concerns about its ability to take abuse (we broke a lot of quadcopters, even with our hastily jury rigged test stand.

Our main constraint was price: I think we set a total of $100 (including the BeagbeBone) for all the components, which included the IMU, a cheap VGA camera, motors, battery, etc. Super proud of the laser cut frame as well, though I bet if we had better access to 3D printers back then we could have printed a frame fairly easily.

This looks really cool, but tbh when I saw the name micro drone I expected something crazyflie-sized[0] more than this.

Which is not a complaint, by the way! The crazyflie is so small that it becomes quite the limitation in a few ways. Really curious how the slightly larger size of the ArduBee compares in practice - probably has a bit more stability and power.

[0] https://www.bitcraze.io/products/crazyflie-2-1/

[1] https://en.wikipedia.org/wiki/Square%E2%80%93cube_law

Thank you! Bitcraze is so small and lightweight, but the first version had 3 minutes of flight time. It have brush motors and it's not suited for outdoor. We'll update you about the real flight time asap the new motors arrive. Furthermore, ArduBee will be proposed as a plain board without motors and propellers, to enable every sort of selection and combinations of brushless motors and 3" props, offering full customization for many different approach, you can use top motors or under the base, for max endurance, max payload, max navigation performance or wind disturbance rejection.

m5stack, the company which puts esp32 and esp8266 into nice boxes has recently teased a m5stack atom drone (atomfly).

https://twitter.com/M5Stack/status/1244209693045567488?s=20

the m5stack atom is a little esp32 in a box.

https://m5stack.com/products/atom-lite-esp32-development-kit...

I am really excited about the ultrawideband implementation! The technology has been around for a few years now but the interface is quite complex and is hard to get up and running.

The actual ultrawideband devices (decawave) are available on digikey for $10-20 each so if a good open source implementation exists, that would be very exciting for hobby robotic makers.

I agree UWB system has good quality positioning, it's not affected by lights or smoke and it's quite cheap. The localization is processed on each Flight Control and it's integrated inside the Arudpilot firmware and passed to the Ardupilot EKF.

so is this like the only programmable drone out there? or is this the only one that is open source ? how much something like would cost? anyone have an idea ?

I don't remember what was the price range but it was cheat. I think we speak about it in the end of their talk in the ArduPillot unconference. Check on ArduPilot YouTube channel for their talk.

What is impressive it the integration on this drone : that give a good flight time with low weight. That is a big advantage against current weight based regulation in numerous country. And of course ArduPilot integration give hight capabilities !

Excuse my noob question but : what do you mean by integration? And why is it important?

It probably means you can build firmware form ArduPilot and burn it into the drone. It's a big deal because ArduPilot is a whole platform and they have a lot of bells and whistles, communication with a companion computer, base station communication, a whole lot of possible configurations.

integration of all the different parts on board in a single base: WIFI with ESP8266 WiFi, brushless motors, 4x ESC last generation BLHeli32 with telemetry and DSHOOT up to 2400 -- FlighControl -- IMU -- baro -- compass -- power system with 1 easily swappable Li-Ion 18650 for maximum flight time -- rangeFinder for accurate low height navigation 0-3m -- sdcard slot for Log -- connector for common RC radio and telemetry + connector for all the external add-ons like GPS, indoor positioning system, optical flow, 8 horizontal rangefinder for collision advoiance,... All these hw connected with the Ardupilot features. Furthermore, for small copter its very hard to have good flight time, ArduBee try to have very good flight time, safe and ready for makers to develop, supported by one of the best Open Source project for drone, Ardupilot. It has been developed to be used safely for urban swarm robotics application development, education, creativity!

https://ardupilot.org/copter/

ESP8266 with Ardupilot (telemetry and control) https://ardupilot.org/copter/docs/common-esp8266-telemetry.h...

BLHeli_32 ESC Telemetryhttps://ardupilot.org/copter/docs/common-dshot-blheli32-tele...

A 5" ArduPilot quad will probably run you about $150, maybe $200 tops, depending.

It's not so easy to stay under $200 if you mean all parts apart the RC radio. I mean 4 motors + 4 ESC BLHEli32 with telemetry + FC + WIFI, compass, 1 down-facing rangefinder, .. in particular for the FC if you select these components with quality chips and sensors it starts to be quite challenging. Furthermore, if you would like to develop swarm applications the time spent to create the fleet is not to be underestimated. Last plus its a platform with 1 single common 18650 LI-Ion battery for higher flight time in comparison to the usual LiPo.

Yes, it depends on what kind of sensors you get. I meant just with GPS, 4 BLHeli ESCs will run you around $40, 4 motors another $40, Kakute F7 controller another $50, $30 for the frame, $8 for the GPS, $10 for the receiver, $5 if you want an extra PDB, it's not that bad.

If you add sensors it does add up though, you're right.

The ArduPilot software platform is used very commonly across the drone industry and this is definitely not the only programmable drone available! The ArduPilot site has a list of some ready-to-use drones that have ArduPilot installed: https://ardupilot.org/copter/docs/common-rtf.html.

A lot of the time ArduPilot is installed with a flight computer (separate from the flight controller) which sends control signals inline with the RC receiver and can be retrofit onto an existing drone.

You can also pick up pretty inexpensive kits to retrofit any DIY quadcopter or RC aircraft with autopilot capability. Two examples are the older APM2.8 hardware (no longer supported, dirt cheap) and the Pixhawk PX4 (actively supported, more expensive but still <$200.)

Ah so if I understand this correctly : on the software side I'm most probably gonna land on ArduPilot, and for the hardware that's were the bulk of decisions will be?

Like bri3d said in his comment, there are a few options -- ArduPilot is heavily focused on mission planning (Waypoints, GPS guidance, etc). There is other flight controller firmware like Betaflight which is more focused on the stabilization and PID control of a quad.

There's definitely a lot of different decisions you can make on the hardware side: Choosing what sensors you include, flight computer & flight controller, ESCs and motors, frame, and so on.

On the other hand, you could also choose to build a drone from a kit or ready-to-fly model, and experiment more with higher-level software. ArduPilot can be connected to ROS, which is the standard software platform for robotics. Much of the swarming behavior, visual tracking, and other experiments are done on a platform like ROS, which then sends waypoints or other instructions to the flight computer.

Some areas to research if you're into this:

ArduPilot (Firmware handling waypoint missions, guidance, etc. on an onboard flight controller): https://ardupilot.org/copter/index.html

MavLink (Standard serial protocol used to communicate with drones, used to communicate between an ArduPilot controller and a ground station): https://mavlink.io/en/

ROS (Software platform designed for robotics, commonly ArduPilot drones feed into a ROS system for swarm experiments etc.): https://www.ros.org/

No and not even close. Look up Betaflight (racing oriented) and iNav (navigation oriented). Ardupilot is more integration/mission oriented, but it's far from the only game in town.

A small <250g drone is in the $70-$100 price range, although you will also need a $70+ radio transmitter or some heavy hacking to control it. Most of the (hundreds) of supported control boards are not open hardware in the schematics sense, but some are.

The all-in-one PCB integration strategy is cute, but I really don't think it's a great approach from a crash-recovery point of view.

> The all-in-one PCB integration strategy is cute, but I really don't think it's a great approach from a crash-recovery point of view.

Spot on.

However, it's a nice way to lure you into building a quad: just put some motors on, and you're good to go.

Fly once, crash, and then go actually build a proper quad.

Small quads generally do remarkably little damage to themselves in most typical crashes. Remember this thing only weighs 102g, and half of that is a battery held on by springs.

In typical indoor use (can't get more than a few meters high, unlikely to go faster than a few m/s), this'll crash way more than one time before it show any signs of damage to anything except the (replaceable) props. (Sure, you won't be handing it down to your grandkids in your will, but it's not as disposable as "fly once, crash, throw it away"...)

I totally agree with you, it's the most compressed form, in a slim electronics layer, for the most lightweight design. Every grams are used for the best selected components, assembled with passion and fully supported by Ardupilot firmware.

I agree -- and beyond a catastrophic crash, I wonder how practical the PCB frame is for longevity of the quad, vibration dampening, etc.

Without catastrophic crashes, it's a flying PCB with the finest micro drone's build integrated in its frame.

About vibration dampening, if you look at the maiden flight here https://discuss.ardupilot.org/t/ardubee-a-ready-to-fly-micro...

Don't you think the untuned ArduBee was flying already nicely?

The graph of the postfilter acc and gyro is not so bad, the new Dynamic Notch Filter technics in Ardupilot is working so good. Furthermore, the best in his class IMU is put in the center of the frame, where the single 18650 battery, the most of the mass, is fixed in place.

I don't know much about the drone space to be quite honest but I always wondered what it would cost to mess around with swarm algorithms, on actual drones, without breaking the bank. Any pointers?

IMO, a lot. Moving things are hard, and drones especially, are _very_ damn hard. One mistake and the drone goes poof! It gets frustrating after a while.

Just some pointers if you want to do this:

- you need some companion computer on your drone.

- GPS alone is not precise enough, you'll get wierd drifts from it all the time, you want something like RTK GPS to be able to keep stuff together.

- If you want your positioning to relie on vision, get a global shutter camera, a rolling shutter will make your life harder than it needs to be.

With ArduBee initiative we are making our best to innovate creating our best solution for swarming, with micro drones, indoor and even outdoor, based on Ardupilot Open Source project. If you have a look at https://ardupilot.org/copter/ you could start to have an idea of the included potential.

Speaking of transmitters, what is a good entry level transmitter/receiver combo to get into for hacking servo-based RC projects? So far I like a Spektrum DX6 controller best I just wish it was a bit smaller for my kid's hands.

Look up the Jumper T16 - it’s a multiprotocol transmitter that supports most of the major brands, which means you’re not tied into any brand receiver.

The Jumper T176 is amazing, if you're going to get a good TX you want to last you a while, get that. If you want a cheap, small one with not too many capabilities but that a child can use, get one of the cheaper FlySky ones.

I've never built a drone yet but I've tried to do a lot of reading, and I don't understand why everything assumes that you have an R/C transmitter in your hand, and then at some point "throw the switch" and make it autonomous.

Isn't the entire point of these things that they fly themselves? That's why we call them drones and not R/C helis, right?

Why can't I just click "go" on my GUI, and never purchase a TX? Or can I and the distinction just isn't explained in a place that I've found it?

That's because Betaflight and INAV have evolved from manual/freestyle flying. ArduPilot is the more "autonomous" platform, which you can fly without a TX. You can add a USB telemetry module to your laptop and fly like that, although I've never done (and wouldn't do) that, there are many cases when you need manual control for recovery/failsafes.

I don't know where you got the idea that autonomy is why we call them drones. FPV drones are all analog and they've been around a while.

They assume you have a transmitter, because a majority of non parrot drone users are flying analog.

Yeah. There was a time maybe 8-9 years back where at least a section of the hobby tried to push back against the people using the term "drone" for any quadcopter/multirotor, and trying to educate people that only things capable of autonomous flight were "drones", while regular non-autonomous quadcopter really are just RC helicopters.

We lost that fight a long time ago.

(And I'm not even sure we were "right" to be honest. The term "drone" got used back in WW2 era for radio controlled aircraft used for target practice. There sure as hell were not autonomous... https://en.wikipedia.org/wiki/Radioplane_OQ-2 )

What drones are autonomous? The most well-known ones, used by the US military, aren't autonomous, AFAIK. A in UAV stands for Aerial, not Autonomous.

At least in the consumer space (which I suspect is what you're thinking of when you say "assumes that you have an R/C transmitter in your hand"), most people over the last decade (and even now in a lot of places) are flying under some interpretation of 50+ year old model aircraft rules.

Here (.au) I'm technically not allowed to fly FPV (where I'm watching a camera view from the air thru goggles or on a screen) without having another person ready to immediately take manual control who's watching/flying "LOS" (line of sight) and complying with the regular model aircraft pilot rules.

Practically nobody actually does this, but almost everybody holds some form of manual controller and is ready to take their goggles off or look away from the screen and fly the drone manually as a regular model aircraft.

If you _want_ to "just click go on the GUI", at least some of the DJI stuff will allow you to do that. I've got a DJI Spark that I can connect/control via wifi from an iPad, and software that lets me define a mission and just click fly without needing a controller. There's still an advantage to having the controller though, it's radio as way better range than an iPad's wifi, the wifi drops out and I lose the video link (while the drone keeps flying its uploaded mission) at a hundred or so meters. If the drone and the iPad both connect instead to the DJI controller, I'll get reliable video at well over 1km. One other reason I almost always use the controller is I'm much happier launching/landing in tight locations if I fly the last few meters manually. I'll sit on the back ledge of the car boot and land 1m away from the car flying manually, but I don't trust the drone/GPS quite enough to do that, and will always find a fairly large (at least 10mx10m or so if I can) area to let it land in if it's flying totally autonomously.

To be blunt: because they're not good enough. Even ArduPilot which is probably the best mission-flying software in the open source space, or DJI who are still ahead in the commercial space, will often need manual intervention to complete a mission.

You absolutely _can_ build an ArduPilot drone that takes commands and tries to fly a mission end-to-end without intervention, but without a real-time TX link of some form, you are in hot water when it fails.

Crazyflie is a tiny flying PCB, original version from ~2013 (no camera) https://www.bitcraze.io/

And yes, it is not very robust, I broke one PCB arm but could fix it without affecting the balance too much.

The bigger problem was encountered when it flew out of reach. I had an xbox 360 controller connected to a xbox wireless dongle on my laptop, running crazyflie SW, connected to crazyfly via another dongle. Tested it in a city park (somebody attended to the laptop).

I moved a bit away from the laptop setup while trying to learn to fly it (manual leveling is hard). I don't know which wireless connection failed first. But the result was, it just kept running the last instruction, and flying up, up and away. Luckily the battery failed when it was up about 50-100 meters, and had drifted away about 100m horizontally due to wind.

I was sweating like hell, picturing scenarios of it coming down on a car windshield and causing a surprised driver to crash, etc. Luckily it came down within the same park. Without new damage to drone, or third parties!

Lessons learned: Don't fly an indoor drone outdoors, it's not built to resist wind and doesn't have SW safe for it. And never, ever fly any drone outdoors without model plane liability insurance.

> And never, ever fly any drone outdoors without model plane liability insurance.

Or be able to run fast ... ;-)

Very cool idea! Looks like something that will allow prototyping automatic indoor flight on a tight budget. The only thing I don't like about the design is that if you break an ESC (or other component for that matter) then you most likely need to replace the whole thing, which won't be cheap.

I wish this had a bit more processing power (or a raspberry pi add on) so that it could run ROS but that would definitely hurt the flight time.

Couple of years ago there was a prototyping board Snaodragon Flight that came with built-in cameras for optical flow: https://discuss.ardupilot.org/t/ardubee-a-ready-to-fly-micro.... I think some people here might find it interesting.

Thanks! we are working hard on the best protection+landing, searching for the lightest solution and it will be all around the propellers. We use since 2 years its bigger brother (220g) in a swarm system for choreographies with medium acceleration/speed autonomous navigation, during all the intense flying sessions we had quite some crashes but the harm on the board has been very low.

The drone seems nice, I hope we can play with it soon ! I am glad they share some development with open source !

Thank you so much khancyr! You are a well-known member in the ardupilot community your support is highly appreciated and if you have ideas or suggestions we would love to have your opinion before closing the new ArduBee prototypes in development

With great excitement we follow the feeback here on HN and we are happy to answer all your questions!

Besides posting here you're all also very much invited to submit your feedback via this google form and contribute with your ideas to the final version of ArduBee before starting the kickstarter: https://docs.google.com/forms/d/e/1FAIpQLSfSv-mjhigMYmZsG03N...

Can you remove the unnecessary loading screen from your website?

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