System Design Help: fully autonomous quadcopter - Page 1
Forum section: electronics / projects

author: technix
author_rank: Super Contributor
timestamp: July 27, 2015, 02:36:02 pm
content: Here is a project idea that a friend of mine and I came up collaboratively, but ended up rejected by him and put on backburner by me. Now I want to revive it but it always seemed to me that a few pieces that I cannot put my fingers to is missing.After acquiring a destination the craft should be able to fly and navigate on its own, albeit with a 3G Internet connection. It have an autonomous system that finds its best course, fly under instrument navigation following such course, avoid collision with other objects using its sonar system, correct its course against the winds, and if such equipment is possible, refuel itself on roof-mounted inductive charging pads.Here is a list of sensors and electronics I think it will need to function:GPS (general navigation)Accelerator (inertial navigation, course correction)Gyroscope (inertial navigation, course correction)Magnetometer (general navigation, course correction)Wi-Fi dongle (inter-craft communication, precision locating)Sonar (collision avoidance, landing control)3G modem (communications, command & control, locating beacon)Inductive charging kit (autonomous refueling)The system consists of two layers of control: Consciousness and Instincts. The lower Instincts layer, implemented on a microcontroller, performs the actual motor driving, and also includes failsafes that will avoid collision, avoid ditching, and land the craft on flat surface when higher control is lost. The higher Consciousness layer, implemented using a Raspberry Pi, controls the direction the craft is going to, corrects the course of wind error, and receives higher control (on the cloud, called Will, which controls multiple crafts in a region - out of scope here)My question is how should such a system be designed?

author: eas
author_rank: Frequent Contributor
timestamp: July 27, 2015, 04:31:21 pm
content: Well, if you want ideas/inspiration, you might want to check out the open sourceArduPilotproject and the hardware that people are using it with (despite the name, its no longer arduino/AVR focused). Earlier versions of the software were used in the popular DJI Phantom quads. It is capable of autonomous navigation.Rather than inductive charging, you might just want contacts on the landing gear. RC battery packs can be charged at pretty high current.

author: technix
author_rank: Super Contributor
timestamp: July 27, 2015, 04:52:54 pm
content: Quote from: eas on July 27, 2015, 04:31:21 pmI am asking for system design help more than project ideas here. I would like to have a bot of reliability built into the system - even when the navigation components are dead I would not lose the craft.

author: mazurov
author_rank: Frequent Contributor
timestamp: July 27, 2015, 05:06:55 pm
content: Sensors are trivial and can be made redundant for little money. Also, some designs (Pixhawk) are quite clever - you can add/remove your own components via numerous buses already present. However, If you never coded anything like an autopilot I suggest grabbing the source of one of the ones already available and taking a look at it. Could turn out that hardware will be the least of your worries.

author: diyaudio
author_rank: Frequent Contributor
timestamp: July 27, 2015, 05:17:02 pm
content: Quote from: mazurov on July 27, 2015, 05:06:55 pmI've had a look at the Pixhawk firmware and do monthly pulls on its git repository, the size of that project is insane, little hope doing something alone from nothing, good luck to you with that autonomous quadcopter design, unless you just adding sensory layers to the existing design.

author: technix
author_rank: Super Contributor
timestamp: July 27, 2015, 05:18:40 pm
content: Quote from: mazurov on July 27, 2015, 05:06:55 pmThis is part of what I am talking about with the "system design" thing. I would like to have two layers of control, "instincts" and "consciousness". Take human walking as an example, our consciousness tells us to which direction we are walking to and wo which angle we are turning to, and it is up to our instincts to actually control our legs. The consciousness layer of control determines which way the craft is going, and the instincts layer of control performs it by driving the motors. Also when the consciousness layer falls unconscious (system locked up, etc) the instincts will take over the sensors and initiate a safe mode to prevent me from losing the craft.

author: technix
author_rank: Super Contributor
timestamp: July 27, 2015, 05:21:07 pm
content: Quote from: diyaudio on July 27, 2015, 05:17:02 pmNo I am making my design from scratch. It seem to me that by breaking the controls up into two layers (consciousness and instincts) will limit the growth of my project, and allow me to have some extra failsafe.

author: retrolefty
author_rank: Super Contributor
timestamp: July 27, 2015, 06:25:24 pm
content: Quote from: technix on July 27, 2015, 05:18:40 pmYou will lose the craft.

author: AndyC_772
author_rank: Super Contributor
timestamp: July 27, 2015, 06:40:21 pm
content: Quote from: retrolefty on July 27, 2015, 06:25:24 pmMuch worse than that... you'll risk losing it into controlled air space. By far and away the most important issue in a project like this will be maintaining enough control over it underallconditions, to keep it out of the flight paths of other aircraft.The thought of an out-of-control homemade drone getting sucked into a jet engine terrifies me.

author: diyaudio
author_rank: Frequent Contributor
timestamp: July 27, 2015, 06:45:37 pm
content: Quote from: AndyC_772 on July 27, 2015, 06:40:21 pmI had a nightmare of something like that, I imagine the engines destroying it like those bird carcass Boeing use to test with.

author: technix
author_rank: Super Contributor
timestamp: July 27, 2015, 07:14:04 pm
content: Quote from: AndyC_772 on July 27, 2015, 06:40:21 pmRemember the layered design, and the instincts layer controls the anti-collision mechanism that is based on sonars? One of the sonars is facing down (also used as a way to land properly) and it is also used as a height limit sensor - when the craft went too high the instincts layer will not allow the craft going up unless it is within certain distance from a wall. This is where the instincts layer failsafe is all about.Instincts layer is all about safety. Putting it into a separate chip is (partly) to make sure that the failsafe mechanism will work all the time even when the higher control is knocked out.Also in the Consciousness layer, since the route planning is all based on waypoints and links, no waypoint or waypoint links will go near restricted airspace or go too high.

author: AndyC_772
author_rank: Super Contributor
timestamp: July 27, 2015, 09:07:09 pm
content: Yikes, a thousand times over

author: eneuro
author_rank: Super Contributor
timestamp: July 27, 2015, 09:43:27 pm
content: Quote from: technix on July 27, 2015, 02:36:02 pmYou forgot about big parachute, while drons have crappy propellers and can fall from the skyDepending on the size of the drone, probably they are much more dangerous than birds which can be cut by engine blades like during those tests

author: helius
author_rank: Super Contributor
timestamp: July 27, 2015, 09:56:42 pm
content: It sounds like you're describing a Subsumption Architecture, which is what Rodney Brooks has been working on since 1980. It can be effective for controlling robots.The bigger challenges for UAVs are safety related. How does the controller react when part of the system has failed or is sending bad data? If the vehicle has a catastrophic failure, what will it hit during its crash? There is no easy way to make it inherently safe.

author: IanJ
author_rank: Unknown
timestamp: July 27, 2015, 10:41:20 pm
content: Technix,If you want a starting point, assuming you have never built/flown a quad before.......then go visit the Aeroquad website and buy a kit with all the options (sensors etc etc etc) and start from there. You'll get exposure to all the hardware and the software, and including a level of self flight (altitude and heading hold).http://aeroquad.com/content.phpI did just that and even built my own RC transmitter. A lot of fun, but certainly an eye-opener and quite complex.Ideas is not enough........you will need a lot of technical help.I haven't mentioned safety as thats a whole different issue, and a big one at that!Ian.

author: SL4P
author_rank: Super Contributor
timestamp: July 27, 2015, 11:09:23 pm
content: Quote from: diyaudio on July 27, 2015, 06:45:37 pmI think your problem lies in that statement...You're inward thinking, and for this project to succeed, you need to have a much greater awareness of what's going on around your craft, than within.Also, you seem to dismiss ArduPilot-ArduCopter very quickly, yet it doeseverythingyou want - and more.it's good that you want to 'start again', but don't look a gift horse in the mouth.

author: mackrc1
author_rank: Contributor
timestamp: July 27, 2015, 11:30:26 pm
content: Solid advice from Ian, seriously if you've never built or flown one of these things before you're going to be pulling your hair out trying to build your own flight controller from scratch. Getting it to simply hover will be a nightmare, let alone incorporating subsystems like GPS, Compass, Barometer, Sonars etcInductive charging is pretty much out of the question a 4500mah lipo will charge at 4.5amps! That means a very large amount of heat! You can always lower the current but charging will take a very long time.Your question "How should such a system be designed" is rather vague to me. You seem to be pretty fixed on your idea of what your going to use and how your system will function as a unit. So are you looking for programming implementation or what?Going off what you have said I would say a good place to start once you are familiar with multirotors isthis article, I've only skimmed through it but it looks exactly like what you are asking for.Cheers,Ewan

author: technix
author_rank: Super Contributor
timestamp: July 28, 2015, 07:38:40 am
content: Quote from: mackrc1 on July 27, 2015, 11:30:26 pmThe system design I am talking about is where, in the three layers of control, should subsystems and sensors go to.Here are my three layers of control:Will: flight control, human interface, etc (on the cloud)Consciousness: navigation, course correction, communication (Raspberry Pi on the craft)Instincts: operation details, safety (Microcontroller on the craft)Here are my current map of sensors:Will: noneConsciousness: GPS (navigation), accelerometer (shared with Instincts, course correction), magnetometer (course correction), gyroscope (shared with Instincts, course correction), 3G modem (communications), Wi-Fi dongle (communications, precision navigation)Instincts: accelerometer (shared with Consciousness, operation details & safety), gyroscope (shared with Consciousness, operation details & safety), sonars (safety)The task of keeping the craft flying correctly is taken care of by the instincts layer which balances the craft based on negative feedback with the readings from the accelerometers and gyroscopes. Then it is up to the Consciousness layer to determine whether the craft should turn to or accelerate at any direction. The safety mechanism is based mostly on the sonars to prevent collisions to other objects (that is, maintaining a minimum distance), and to tether the craft to within a certain maximum distance from a surface. The task of controlled landing is also done in the Instincts layer with sonar help.Charging is now done by landing on roof mounted charging pads and electricity is conducted through contacts on landing gear. The contacts is also used as a ditching sensor (ditching means landing on water, and whenever the landing gear contacts are shorted out the landing is considered ditching and aborted)Some safety mechanism is also included in the higher levels: the waypoint-based route planning (happening in the Will and Consciousness layers) only include safe waypoints and airways. Also every craft have a Wi-Fi dongle that is used to communicate with other nearby crafts to prevent craft to craft collision.

author: AndyC_772
author_rank: Super Contributor
timestamp: July 28, 2015, 07:53:21 am
content: Just so we're clear... this device is only ever going to be flown inside a confined space with no other aircraft to hit, and no possible way to escape into free space, right?

author: technix
author_rank: Super Contributor
timestamp: July 28, 2015, 08:11:31 am
content: Quote from: AndyC_772 on July 28, 2015, 07:53:21 amYesThe sonar system will make sure the craft will be always within a certain range from a surface, not too far, not too close, unless it is landing. It and will can be flown outdoors, but the routing subsystem and safety subsystem together will not allow it go out of a safe zone.

author: Jeroen3
author_rank: Super Contributor
timestamp: July 28, 2015, 08:14:08 am
content: How many hours are you willing to put in?

author: coppice
author_rank: Super Contributor
timestamp: July 28, 2015, 08:15:57 am
content: Quote from: AndyC_772 on July 27, 2015, 06:40:21 pmI used to fly RC helicopters. By far and away the most important issue in a project like is keeping it out of the faces of children. Next is keep it out of the faces of adults. Third is keeping it away from anything expensive it might damage. Unless you are somewhat close to an airport its highly unlikely your craft would get high enough to be anywhere near an aircraft. Children are everywhere, and love running towards anything that flies.

author: helius
author_rank: Super Contributor
timestamp: July 28, 2015, 08:51:58 am
content: Goes into what you need to build an autonomous UAV system. They have been doing this for a decade.https://github.com/paparazzi/paparazziOne of the critical pieces of infrastructure for these experiments is a skilled human RC operator to monitor the aircraft. Airborne robots are qualitatively different from land or sea robots because they can completely self destruct in seconds for any reason. Operating them without an effective backup control channel is just irresponsible.There are other parts of your plan that just don't make sense, including sonar for obstacle avoidance (works fine for indoor robots at under 1m/s, and not at all at high speeds in choppy air with high winds).

author: SL4P
author_rank: Super Contributor
timestamp: July 28, 2015, 09:07:34 am
content: Quote from: retrolefty on July 27, 2015, 06:25:24 pmNice project idea...Your table of control and sensors may be worth revisiting as a matrix to see where their requirements overlap.The idea of a Pi as primary and a micro as fallback is sweet, but remember they have to beinterdependent (working together) from before take-off.Possibly better to design the control model as dual-platform with diversity and redundancy - running on different processors to avoid single-point-of-failure.The micro's ability to return to base without flying through danger is just as important as flying out to start the mission. You can do a lot of damage in both directions.An autonomous, intelligent drone is not impossible, butisa big step up from R/C models.Perhaps this guy lives near you?

author: technix
author_rank: Super Contributor
timestamp: July 28, 2015, 10:10:05 am
content: Quote from: SL4P on July 28, 2015, 09:07:34 amIt is interdependent from the get-go: the Pi never controls the motors directly, and without high command from both the Pi and a RC control channel the micro defaults to a failsafe mode that lands it to the nearest safe location and turns on a distress beacon. Flight under no high command is extremely limited.

author: IanJ
author_rank: Unknown
timestamp: July 28, 2015, 10:29:34 am
content: Quote from: technix on July 28, 2015, 10:10:05 amTechnix, you don't just chuck in a safety system like that and you're done.......if that was the case many aspects of our lives would be autonomous already.I used to say to the guys at my old workplace (electronics & software)........"it's easy to make something do what you want it to do, but it's hard to stop it doing what you don't want it to do".In your case, you're gonna come across a LOT of hurdles along the way, and a LOT of surprises also that will increase costs, increase weight, increase complexity, decrease reliability, decrease safety.......and thats before you ever turn a motor. You have a HUGE undertaking ahead.Sounds a bit like Amazon's idea to delivery parcels by drone (which IMHO was just a marketing excersize).............Ian.

author: technix
author_rank: Super Contributor
timestamp: July 28, 2015, 10:45:19 am
content: Quote from: coppice on July 28, 2015, 08:15:57 amThe initial plan for the safety distance is at most 10 meters from any surface, at least 50 centimeters from walls or the ceiling, and at least 2.5 meters from ground. I think this will make sure my craft is clear of children's reach.

author: SL4P
author_rank: Super Contributor
timestamp: July 28, 2015, 12:04:33 pm
content: Quote from: technix on July 28, 2015, 10:10:05 amI think you're missing ahugepart of the requirements to develop a safe and reliable flight and return platform......inter-dependent is not the same as dependent.How does your craft get down safely if the micro or drive system dies in some way?In all your offerings, the Pidependson the micro.Can your flight control system fall back to losing a rotor?How does it know one has failed?If the Pi locks up, does a second high-level controller take over? How does the micro determine the safe ditching strategy?add more scenarios here. start with the sensor and control matrix.

author: technix
author_rank: Super Contributor
timestamp: July 28, 2015, 02:32:21 pm
content: Quote from: SL4P on July 28, 2015, 12:04:33 pmThe loss of consciousness failsafe mechanism is not flying back in the first place - it just lands the craft at a flat solid surface, turn on the search and rescue locator beacon, and render the rest of the system inert until it is physically reactivated (which requires partially disassembling the craft)A failed mechanical component (e.g. losing a rotor) will knock the craft out of service anyway, but such a conscious failure will cause the Pi to send out Mayday signal back to the central control with its GPS location, allowing easier recovery of the craft and avoid losing it as much as possible. And the detection of a failed rotor is based on out-of-norm inertial sensor readings and motor current.

author: eneuro
author_rank: Super Contributor
timestamp: July 28, 2015, 04:02:35 pm
content: Quote from: IanJ on July 27, 2015, 10:41:20 pmDrones are useless as UAV's, since flat battery or motor failure means uncontrolled fall from the sky and only huge parachute could help save something on the groundHow do yo think why U.S. Army UAV's are more gliders than bloody quadcopter drones-that is simple-even if its engine stops working for some reason one can still try use thermics to fly away at safe place to make controlled landingForget about bloody drones if you want to have reliable UAV

author: SL4P
author_rank: Super Contributor
timestamp: July 28, 2015, 04:07:13 pm
content: OP, I don't doubt that many of us admire your enthusiasm.And that's all I have to say about that.

author: idpromnut
author_rank: Unknown
timestamp: July 28, 2015, 04:09:48 pm
content: Quote from: technix on July 28, 2015, 10:45:19 amSo what happens in a "regular" room that has a ~3 meters ceiling? And which has dimensions of 4m x 5m? Which surface should it try and "keep away" from?

author: diyaudio
author_rank: Frequent Contributor
timestamp: July 28, 2015, 05:08:26 pm
content: Quote from: SL4P on July 27, 2015, 11:09:23 pmArduPilot-ArduCopter is great no issue with it but..., flash memory on that project is running out, its probably at 80% of its flash capacity as a result of its fat Arduino eco system, where pixhawk is better in many respects example its running, an ARM M4 core, inherently better debugging facilities (not that stupid Arduino IDE), its faster with 1Mb of flash with all the essentials to ease development and favour future updates .. also note, the pixhawk mission planner software is written in QT instead of .NET, so it runs on lots of platforms, its just smoother as it doesn't suffer warm up time as a result of using .NET, its just better.ArduPilot is still great but lets move with the times now shall we.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 28, 2015, 07:56:57 pm
content: stage 1 (out of 5 or 10 maybe)... just to hover a plane stably (without any brain yet).... please buy (or get) and read and master this first...http://www.amazon.com/Adaptive-Control-Theory-Guaranteed-Robustness/dp/0898717043this is how they do and sell a "remote controlled quadcopter", no brain no autonomous, just "remote controlled". when you are done... come back and PM me i have some thicker books to suggest to make your copter to have some bit of a brain... as i know it, you wont have much time "foruming" for a very very long time if want to accomplish this level of enthusiasm... so there it is...Quote from: eneuro on July 28, 2015, 04:02:35 pmthats the secondary reason, i believe the primary reason is because its a fixed wing type aircraft. that its purpose... and i believe for military purpose, landing in a miscellaneous safe area is not an option, its better being destroyed up in the sky rather than being recovered by miscellaneous people. and i doubt any US military drones/UAV have some level of conciousness or instinct as OP desired.

author: SL4P
author_rank: Super Contributor
timestamp: July 28, 2015, 11:20:41 pm
content: @diyaudio... Agreed on your points re: Arduxxxx. No argument.That reference was for a convenient, well developed starting point that I have some small awareness of.There is a good case for 'standing on the shoulders of others', and from my understanding, the core group of developers for Arduxxxx have around 120 years of combined systems and professional data wrangling between them - some with very large companies, including defence contractors.Why not look and learn from open-source efforts to soften the starting point!

author: eneuro
author_rank: Super Contributor
timestamp: July 29, 2015, 07:51:06 am
content: Quote from: SL4P on July 28, 2015, 11:20:41 pmBecause of quadcopter drones are holly crap itself no wings no chance to fly on flat battery even when we have decent altitude.It may be worth look at those alghorithms and learn by example by it is still noisy quadcopter which will fall from the sky without any chance to use altitude to glide to safer area of landing....Basicly this kind of drones is a crap and just working on laser guided gun or raptor glider with net to shot down or intercept this crap if they will try fly to close to my yard

author: SL4P
author_rank: Super Contributor
timestamp: July 29, 2015, 07:53:47 am
content: Didn't take your happy pill today!

author: eneuro
author_rank: Super Contributor
timestamp: July 29, 2015, 08:20:09 am
content: Hopefully, sometimes no guns needed to take down this "multi crap" and T-shirt is fineAngry gentleman, possibly inebriated, breaks $1,350 multicopterQuoteAnother example there-successfully shotdown bloody droneUpdate: Here we can see that this bloody drone HIT this man legSo, despite what stupid drone owner said:QuoteDrone owner should pay this man who was hit by his drone-if it didn't fly to close to this man probably drone couldn't hit himWhat a donk- he flyies bloody drone so close to people with bloody propellers not guarded by safety enclosur eand claims lawsuit vs a man who was fighting to safe himself while basicly those propellers are dangerous and couls easy harm his eyesShoot down all this carp, especially crappy drones which have not protected propellers-they should be shotdown by police and its owners should pay for flying them so close to people-they should be banned in public space.Hopefully, I usually have on hollidays tennis racquet made of kevlar and tytanium, so this bloody multicopter could be completely destroyed if someone tried fly such crap so close to meUptade2: Those donks wrote on youtube, that this man was drunk, but this man had perfect position and perfectly hit this crappy droneThis man doesn't looks like he is drunk at all-he is walking like a normal strong man, not this idiot carying antena and controll unit, who was not able react fast enougth to flay drone away from this man

author: Jeroen3
author_rank: Super Contributor
timestamp: July 29, 2015, 10:07:20 am
content: I don't get it. The man approaches the drone and hits it? He could've just not cared about it, ask the pilot to not fly in his yard, and leave.But yeah, Americans, special folks.Our government recently funded three companies to develop anti-drone systems.http://tweakers.net/nieuws/104345/overheid-stelt-1-komma-75-miljoen-beschikbaar-voor-dronebestrijding.htmlBut I would rather see this company (also dutch) see with their variant.https://en.wikipedia.org/wiki/Goalkeeper_CIWS

author: technix
author_rank: Super Contributor
timestamp: July 29, 2015, 02:03:24 pm
content: Quote from: idpromnut on July 28, 2015, 04:09:48 pmThis is not for indoors using, the "ceiling" or "walls" or "floor" I am talking about here are obstructions that is occurring in that direction.

author: eneuro
author_rank: Super Contributor
timestamp: July 29, 2015, 03:54:13 pm
content: Quote from: Jeroen3 on July 29, 2015, 10:07:20 amWhy not care about crap flying around someone walking on the street within a range lower than 100 meters?Here is review of this thing: DJI Phantom 3 Professional Review - Is It The Perfect Drone?Professional drone has not protected propellersThere is a lot of this sort of quadcopters around - they should be banned, and if someone banned one of them on the street that is fine, byt its manufacturers should be charged for selling this flying crap or its owners who fly them in public places, because of it is not on privacy concern but also this crap can be dangerous for human body, especially eyes if propellers are not protected at all and those folks named this thing professional crapThere is good place for those quadcopters-in Dave's bin at his labI wish @EVVBlog didn't rant those bloody unsafe quadcopters with pure stupid propellers-it is a crap and crap schould land in BIN

author: Jeroen3
author_rank: Super Contributor
timestamp: July 29, 2015, 04:49:29 pm
content: A chainsaw does more damage, yet you can buy those at the local hardware store...Please elaborate why drones should be banned?

author: technix
author_rank: Super Contributor
timestamp: July 29, 2015, 04:54:06 pm
content: Okay you guys have derailed this thread totally... I am going to ababdon...

author: EEMarc
author_rank: Regular Contributor
timestamp: July 29, 2015, 05:20:48 pm
content: ReleventDilbert comic.

author: eneuro
author_rank: Super Contributor
timestamp: July 29, 2015, 08:23:46 pm
content: Quote from: technix on July 29, 2015, 04:54:06 pmI've paragliding license and I was tought to fly on mountains hill like an Ikar many years ago, so for me safety is above all when we put something into the air which could fall from the sky in public space, so I'd suggest read first what FAA says about unmanned aircraft systems, then try to find electronics to fit into those requirements if autonomic UAV's are not banned in public air space where you want them to fly...https://www.faa.gov/uas/regulations_policies/https://www.faa.gov/uas/model_aircraft/QuoteIt is not clear what near means, but when drone can hit a man like in shown videos above, It means it was too close and that all about it...

author: mackrc1
author_rank: Contributor
timestamp: July 29, 2015, 09:01:54 pm
content: Since this thread has turned sour, I would like to point out that a home drone such as the DJI Phantom is not as dangerous as people are saying it is. It can cut you and it might possibly harm you but so can a knife. I believe in Mythbusters latest episode they concluded that your average drone is not going to slice your jugular. They did however test a larger drone (large hexacopter or octocopter cant remember) and it managed to cut down to the jugular. You have to remember on top of this how unlikely a 'drone' is going to hit you square in the neck. Cant believe gun laws haven't been sorted over in the US yet they are having a fit at a plastic 'drone'.Ewan

author: IanJ
author_rank: Unknown
timestamp: July 29, 2015, 09:36:03 pm
content: Quote from: mackrc1 on July 29, 2015, 09:01:54 pmI hear that!!In my opinion as a quadcopter builder & pilot myself, and having played with many motors and prop sizes, I'd say NO quadcopter regardless of size etc should be flown in any public place or within any reasonable reaching distance.Just imagine your DJI Phantom flying into a 3 year old kid's face and the carnage as a result.......just because the sun got in your eyes and you lost sight for a few seconds, or because a prop broke, or hit a bird and the quad went haywire.A quadcopter should be flown just like any other RC aircraft and thats well away from anything. Unfortunately, the nature of the beast is that flying in public places makes for much more interesting flights.Safety first........end of.Ian.

author: eneuro
author_rank: Super Contributor
timestamp: July 29, 2015, 09:43:40 pm
content: Quote from: mackrc1 on July 29, 2015, 09:01:54 pmReally? Do you have in the kitchen flying knife?Anyway, thank you I've found this part of Mythbusters episode with this remarkable test, so provide it please when you see on youtube marketing spam promoting those bloody quadcopters without protected propellersCan a home drone kill you? This test with a chicken says maybe!As we can see in this video above, quite safe small black drone with propellers hidden into enclosure hits episode authors neck before final chicken cut showdown, but it couldn't harm him since it has at least protected propellers in horizontal surface.So, it can be done in a safe way, bt some donks promote unsafe quadcopters and claim them perfect drones like this bloody P3 proffesional

author: mackrc1
author_rank: Contributor
timestamp: July 29, 2015, 10:30:05 pm
content: Quote from: eneuro on July 29, 2015, 09:43:40 pmTruly a naive response, Ill say nothing more on that.I knew you would show me that video! If you'd watch the full episode instead of firing away at your keyboard you'll see the real test, that initial test is a proof of concept. Notice how they are pushing the blade into the chicken and notice how long it is there for. Also they are using the blade as a cutting tool by positioning it just the right distance from the chicken stopping the blade losing all of its momentum. The chances of all that happening in real life is next to nothing.I'm not saying people should be allowed to fly these things willy nilly but they should not be slammed because a few people are desperate to maintain their act of maturity.so I'll say it once again ...You seem to be pretty well grounded so I'll say no more on this matter.

author: retrolefty
author_rank: Super Contributor
timestamp: July 29, 2015, 10:34:22 pm
content: Trust me, I've been 'caught' once by a prop from my electric flying wing and it was a quick trip to the hospital to get stitched up. Rear facing prop makes hand launching a rather exacting process that I didn't quite pull off correctly. Those Quad-props should be shrouded with even light weight plastic and a lot of risk and danger would go away.

author: Jeroen3
author_rank: Super Contributor
timestamp: July 30, 2015, 06:40:51 am
content: Quote from: technix on July 29, 2015, 04:54:06 pmBut we didn't even mention the moral complications of helping someone from China build a potential autonomous weapon system.However, drones are perfectly safe. Model helicopters are not.http://www.dailymail.co.uk/news/article-2413231/Roman-Pirozek-Jr-Man-decapitates-remote-control-helicopter.htmlDo you have an system overview designed yet, you should have a basic idea of the specifications before you start?What accuracy of GPS are you aiming for, what gyro, what compass?

author: technix
author_rank: Super Contributor
timestamp: July 30, 2015, 09:15:17 am
content: Quote from: Jeroen3 on July 30, 2015, 06:40:51 amIf you know me you will know that I am definitely not the kind of person that can own any weapon - I am lucky that the government is not sending assassins after me.

author: Mechatrommer
author_rank: Super Contributor
timestamp: July 30, 2015, 09:42:34 am
content: Quote from: technix on July 29, 2015, 04:54:06 pmNot me... b4 u leave,dont forget d book title i mentioned, go get it. that is a good read and 1st step in your dream.

author: miguelvp
author_rank: Super Contributor
timestamp: July 30, 2015, 12:40:22 pm
content: Just put blade guards on your design, as for the high horse people, don't worry, they won't get off because they'll be afraid to break their necks.

author: eneuro
author_rank: Super Contributor
timestamp: July 30, 2015, 05:48:19 pm
content: Quote from: Jeroen3 on July 30, 2015, 06:40:51 amChina military already have such systems and they do not use crappy quadcopters which can fly 15-20 minutes or soAnyway, laser destroyer of this sort of flying crap sounds well regardless which country develops itChina successfully tests laser weapon to shoot down drones.QuoteBigger boys are interested now in not crappy quadcopters but thisFarthest flight byhoverboard - Guinness World RecordsQuoteLess than 1km one year ago, so lets beat this and forget about holly crap quadcopters.