Green spud gun propellants?

In terms of spud guns, I'm assuming that the standard propellants aren't quite "green". Does anyone know of another way of doing it?Or is it innately eco unfriendly?

Question by SenaCat   |  last reply


Gadget Gangster Propeller Platform

The Propeller Platform Module (pictured below) includes an 80Mhz, 160 MIPS Parallax Propeller microcontroller, 32kb of EEPROM with space for a second EEPROM, 5V and 3.3V Voltage Regulators and the pin sockets to add additional Gadget Gangster Platform modules like the LCD UI Module or the Prototyper Module.All Gadget Gangster Platform Modules utilize .1" pin spacing and are breadboard compatible. Here's a little video demonstration of the LCD UI and Propeller Modules: What is the Gadget Gangster Platform?The Gadget Gangster Platform is a lot like the Arduino with a few improvements on the basic idea;-Modules (a.k.a. shields) can be connected to each other on top and bottom. For example, you might have a Propeller module in the middle, an LCD UI on the top, and a prototyper on the bottom. We've got a few initial modules to start, and we'll continue to expand on the selection with more modules and microcontrollers.-Pin spacing is .1". This makes the Platform compatible with breadboards, and it lets you use Platform modules in combination with other project boards.-The board footprint is 3.8" x 2.5", which is the same footprint as ExpressPCB's MiniBoard service. This makes it easier to add your own custom module.-Because they're featured in Jon Williams' Spin Zone column in Nuts and Volts, they're well documented. The Propeller Platform Module will be the basis for many of projects described in his upcoming columns and the LCD UI module will featured in his September '09 column. -Platform Modules are licensed under the MIT license (essentially public domain), giving you the flexibility to use the design in commercial products or anything else without restriction.[/list]I'm super-excited about these new project boards. There's more info on Gadget Gangster but if you have any questions, you can just reply to this thread.

Topic by Gadget Gangster   |  last reply


Motor/propeller selection for quadcopter

Hello Instructables! We are a team of engineering students that want to get started in the world of multirotors. Our objective is to build a long endurance/high payload quadcopter for industrial applications, and we plan to innovate in the power system area. So, without further ado here's our first problem. I've searched the internet for a while now and I've struggled to find information on how to choose an appropiate motor-propeller combination. I know the total maximun thrust should be a bit more than two times the the total weight but motor and propeller manufacturers rarely list the "thrust per rpm" of their props. Our initial estimation for the quadcopter's total weight is 3,3 kg. considering 200 g for each motor. I did manage to find this static thrust calculator but I have no idea how reliable it is since it doesn't say how the thrust is calculated. (http://personal.osi.hu/fuzesisz/strc_eng/index.htm) So that's about it. Any help would be greatly apreciated, no matter how small. It can be advice, information sources, or even builds that are similar to what we want to make and have already been tested. Thank you very much for your time! PS: Excuse me if my english sounds a bit weird, it just isn't my native language.

Topic by Joakov   |  last reply


can ducted propeller produce twice lift compared to opened propeller ?

Can ducted propeller produce twice lift compared to opened propeller ? for example if there is an opened propeller with low rpm producing some amount of lift. If we ducted that opened propeller and provide same rpm and power as opened propeller to it will it produce twice lift compared to opened propeller with same rpm and power ?

Question by MuhammadK19   |  last reply


small solar panel, motor and propeller

I have constructed a desktop solar helicopter that I have on wire3d.com  I am trying to make a small very light solar helicopter that I can fly on the desktop and is tethered on 4 corners. I will make it out of very light plastic or styrofoam or bulsa wood. I need to find the right panel, motor, and propeller. Any suggestions will be appreciated.   bob

Topic by solartoys   |  last reply


Is there a specific twist to airplane (rc) propellers?If so, can I make one at home?

I am working on creating an rc plane but cannot figure out how to find the correct propeller size. Is there a company that sells these?

Question by    |  last reply


How to make a magnetically powered/propelled vehicle ?

I'm a freshman in high school doing a Year End Project (YEP) for STEM. My project is a vehicle that is propelled by electromagnetism. I have three main idea's already. Option 1: Completely replace wheels with large magnets with either a North or South charge. Then replace normal roads with railings charged with magnetism of the same polar to the cars. The bumpers could be magnetically charged as well. With all car bumpers being the same polar, it would decrease the chances of accidents. Take into account that this idea has only started growing for the past 2 years so my ideas for the mechanics are not close to completion so I'm leaving those thoughts out. Option 2: keep the wheels but modify them to have 2-3 smaller magnets on the inside of the wheel. By turning and switching on different a polar changing direction between forwards and backwards. Then add the same idea with the bumpers for the same reason. This cuts the cost exponentially. Option 3: Keep the wheels and everything else of a normal automobile except the engine. Replace it with on large magnet that's stationary and a smaller magnet that can rotate or switch between North and South polar's. Possibly instead of only one pair of magnets increase to an unknown number to allow for more speed, braking and acceleration power. Still keep with the bumper idea. I can't seem to find a reason other than cost to get rid of it. Of course the magnets would interfere with electronics. I haven't thought of a solution for that problem as of yet.

Question by 085070   |  last reply


Recommendations on propellers/controller for over 100g body.

Hello everyone,I am currently trying to build a DIY drone. I have never involved myself in any sort of creating drones. My current project is about making a drone with a morphing body we created. Previously, we just purchased a pre-made drone and took apart all the necessary components and re-attached all onto the morphing body. But the drone we used is this model : Holy Stone HS170 Predator Mini RC Helicopter Drone 2.4Ghz 6-Axis Gyro 4 Channels Quadcopter Good Choice for Drone TrainingThis product can make things fly when the weight is over 30~50g. Would you be able to recommend some products or any sources that can be useful for building a DIY drone? Thank you!

Topic by melonmelon11   |  last reply


HOW TO PRODUCE MORE THRUST IN A REMOTE CONTROLLED QUADCOPTER ? 1]LONG PROPELLERS LESS RPM or 2]SMALL PROPELLERS MORE RPM

I ALSO NEED ANY RELATIONAL FORMULA  BETWEEN  LENGTH OF THE PROPELLERS , WIDTH  OF THE PROPELLERS , RPM (rotation per minute) AND THE THRUST PRODUCED . ANY OTHER DETAIL ABOUT QUAD COPTER ( or any other flying vehicles ) CAN ALSO BE STATED.     THANK YOU!!!!!!!! 

Question by RAGHUL NM   |  last reply


Quadcopter Motor Type? Answered

Hi, I'm working on building a quadcopter.  I have everything figured out, but I'm wonder what motors (and where) I should get.  I would also like that motor to have a propeller mounted on it.  I have seen many Instructables for quadcopters, but none of them specify the motors/propellers.  If you could answer this, please do!  Thanks.

Question by Fission Chips   |  last reply


Can two electric trolling motors with different propellers and maximum RPMs be used effectively on the same boat? Answered

I am building a solar powered electric boat. I want to use more than one motor on the transom. I was wondering if using two motors with different maximum RPM, power, and propeller shapes was possible? Would the propeller of the less powerful motor just add drag or would it add power? Obviously this isn't very specific, but I'm really looking for an explanation or proof of concept. Thanks very much in advance community!

Question by DELETED_craz meanman   |  last reply


how to make electric r/c boat?

I want to make a boat for school with an electric powered battery motor with a switch, which can drive a propeller in the water. it must be water proofe but if it cant anything as close as possible.

Question by    |  last reply


Rubber band aeroplane is not flying correctly

Created Rubberband aeroplane ,and glides fine without propeller.But when the propeller is turned ON ,it just lost the balance and its not climbing into height.The propeller is home made.what would be the reason?.please help me.

Question by AnasCS   |  last reply


wind generator ?

Has anyone had experience in using magnets to help propel a horizontal wind mill or vertical wind turbine .what I mean is putting them in a circular series where the north propel against the north creating , forcing or helping the windmill to move in a circular motion?

Question by junkyardenergy   |  last reply


The Ultimate Water-Powered Rocket!

NASA and the Air Force Office of Scientific Research (AFOSR) have launched a water-powered rocket 1300 feet into the atmosphere!The rocket was actually propelled by a frozen mixture of "nanoscale aluminium" (isn't that "dust"?) and water, pumped in at the consistency of toothpaste and then frozen in place. The propellant is known as ALICE (aluminium and ice - convenient, eh?)Earlier this month, the collaborative team, Drs. Steven F. Son and Tim Pourpoint of Purdue, Rich Yetter and Grant Risha of Penn State, Vigor Yang of Georgia Tech, Harold Bell and Frank Bauer of NASA, and Mitat Birkan and Thomas Russell of AFOSR watched as the rocket soared high into the sky, to 1300 feet near Purdue University.ALICE is generating excitement among the researchers because it has the potential to replace some liquid or solid propellants. It is a promising propellant energetically. Theoretically, when it is optimized, it could have a higher performance than a conventional propellant. In addition, because of the abundance and easy handling of the raw materials, ALICE could potentially become the propellant of choice for missions leaving other planets, since it could be (relatively) easy to manufacture from local raw materials and far easier to store than cryogenic fuels. Story from Wright-Patterson Air Force Base via Rocket Dungeon.Video found by Jeff-O

Topic by Kiteman   |  last reply


Why my quadcopter not fly?

I guys, my problem is that my quadcopter not fly, my setup is: - Motor: 4xNTM 28-26 1200kv 286w http://www.hobbyking.com/hobbyking/store/__17345__NTM_Prop_Drive_Series_28_26A_1200kv_286w.html - Propellers: 4xPropeller GWS 10x4.5 https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=31129 and https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=35243 - Esc: 40A https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=36686 - Frame: SK450 Glass Fiber https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=32537 - Battery: Turnigy nano-tech 4500mah https://www.hobbyking.com/hobbyking/store/uh_viewItem.asp?idProduct=36234 - Controller: Arducopter The total weight of this quadcopter is 1200g. I don't know why not fly, when I put the throttle to 2000 (max power), the copter is lifted a few centimeters(5 cm). can you help me? thanks  in advance :)

Question by AndreaP117   |  last reply


Programming?

Does anybody else on this website know how to program in SPIN? Haven't seen much Propeller programming on this website...

Question by blinkyblinky   |  last reply


How many analog outputs does the Parallax Spin Stamp have? Answered

I have been looking forward to getting a microcontroller with analog outputs, but I need to choose whether I should get the Spin Stamp instead of a bulky Propeller board.

Question by VirtualBoxer   |  last reply


Experiment on whether and when a stuck up fan will break into flame.

Let us consider a typical home electric fan, and we put some obstacle to prevent the fan propeller from turning, then we switch on the fan on the fastest speed; will the fan and when eventually break into flame because the propeller cannot rotate? Have there been experiments to see what will happen? Marius de Jess

Question by Marius de Jess   |  last reply




How to power a brushless motor

How can i power a motor like this (with 3 pins) just to max speed? it's for a propeller clock. thanks

Topic by bfernandes1   |  last reply


Is there a specific ratio between lift and wing size? Answered

I am working on an rc plane and wondered if there is a ratio between propeller size to wing size, wing size to lift, or weight to wing size. Thanks!

Question by DELETED_afw11   |  last reply


Turbine Jet engine...? Answered

If the intake turbines' speed is regulated by the compressed exhaust over the rear turbines, would it be more effecent to have 2 props in a row, or a single large one at the rear of the engine to control the rotation speed?

Question by shawneegeek   |  last reply


Does anyone know how to convert the three phase output from a brushless motor/generator into straight DC voltage?

I would like to pedal the brushless motor/generator to drive a propeller powered by the resulting voltage Thank You?

Question by adamalbert   |  last reply


How can I make a homebrew EEPROM programmer?

Hi everyone!  I have some EEPROMS I would like to burn (27C512, 27C256, 24C256).  I have a Parallax Propeller, a Z80, a 6502, and an Arduino Uno to help me make an EEPROM burner.  I know that EEPROM burners run $40+ commercially (even on EBAY!), so I would like to try building my own at home.  I have an abundant supply of 74XXXX chips at home, as well as a good supply of capacitors and resistors.   I don't have a Parallel Port on my computer, but I have a USB port as well as an RS232 to USB converter.  I'm running Windows XP and Ubuntu - Lucid Lynx 10.04, so if I need a specific OS to burn these EEPROMS, I have Windows and Linux. I need an EEPROM burner that could  erase/burn the 27CXXX EEPROMS/EPROMS/PROMS.  I know through using the Propeller that I can write to the 24C256 through the Propeller, but could someone please help me in building a homebrew EEPROM burner?

Question by prrgg14935   |  last reply


What should the wires connect to if i took an RC Jet ski servo motor out of it ?

I recently took apart a RC Jet Ski. Within the Jet ski there was a servo for the rudder, a impeller to take out water that had been splashed in side and a motor with loads of wire leading to it, to drive a propeller (Jet ski's don't have propellers but this one does. I Need to know what wire leading up to the RC servo motor do (green and brown). If I were to take the wires and use them on something else whhat shall I controll them with? My first thoughts were that sending an electrical current though the postive, would make it turn one way, and by the RC control, electrical currents could be past though postive and negative to make it turn left and right. I know what all of the other wires do. Thanks Oscar 

Question by oscarthompson 


What is the optimum amount of rubbing alcohol for explosions?

I am working on a mini-cannon based project. The cannon has a chamber with interior volume of 15.2 cubic inches. For propellant I am using rubbing alcohol (isopropyl alcohol) that is electronically ignited. The barrel on this gun is about 2 feet of 6mm tubing, designed to shoot Airsoft BBs. I was wondering if anyone knows what the ideal amount of rubbing alcohol to use was (I am using 70% alcohol now, but i can get at least 90% at the store). I could also possibly use butane or propane, if that is better. I went on the internet and looked up the stoichiometric ratio for isopropyl alcohol, but that just told me "1mol fuel to 4.5 mol oxygen at 100 percent concentration." I am not mathematically or scientifically capable of turning that bit of info into a usable amount. 

Question by ilpug   |  last reply


How to build one of these electro magnets?

Ive seen plans to build electro magnets where a metallic object is dangled upside down. this company inverts it so the metallic object is propelled upwards. from some of the pictures ive found it looks to be four magnets working together. any one have any info on building one from scratch? the first site below have videos of it in action. http://www.floating-lamps.com/floating-technology/ www.crealev.com

Question by autoflow 


Why is my quadcopter toppling when i try to fly it?

I built a quad copter. I have done all the calibrations correctly (accel, compass, rc, esc). When I arm the drone, motors and propellers are spinning. But when i give more throttle to try to hover it, it doesnt fly upward steadily. Instead it lifts backwards and falls. Why is this happening? Should I change some PID setting?

Question by prash319   |  last reply


How does the Bernoulli effect affect the ground effect?

I have been wondering about how ekronoplans work with consideration of the Bernoulli effect. Ekranoplans such as the Caspian Sea Monster often have there engines or propellers pointing on a downward angle, this is to push as much air under the wings as possible, in doing this they are forcing the air into a constriction being the wing and the ground, now why doesn't this cause a vacuum pulling the craft down?

Question by The MadScientist   |  last reply


Micro drone construction help

For a school project a partner and I are attempting to build a self controlling quadcopter. It should be able to use a specific input from a photo transistor and the be able to navigate on its own. The only problems that I can see running into at the moment are finding an atmega compatible rotor controller, and that not including the propellers it is going to be under two inches (5.08 cm). I would appreciate any assistance possible in finding a motor controller of this size, and will keep this post up to date with our project.

Topic by Kaptia Teramo 


Anti-RPG Quick Kill system - Slo-mo Defence System Goodness.

'the Raytheon system uses an electronically-scanned radar array to detect an incoming anti-tank rocket-propelled grenade, then vertically launches a countermeasure missile that blows the round to smithereens in mid-flight, saving the RPG's intended target.'All i know, is its one cool slo-mo video, that, and alot of tanks and vehicles are taken out by RPG's, so its a great step forwards.Via Gizmodo

Topic by gmjhowe   |  last reply


How to create wings for human flight?

All of us have seen humans fly in those triangle shaped gliders. How about creating wings that will do the job? Understood that it requires more than wind to propel it so flapping power could be harnessed.  I need designs and the physics(i.e How much area of wing is required to lift what mass of body and etc.) Please suggest solutions ASAP! My e-mail id is bharadwaj.adiraju@gmail.com Thank You :D

Question by bharadwaj.adiraju   |  last reply


Has anyone added springs to a rubber band car? Answered

If so, how did you add them? Did you add it to the stationary point? Will this addition help with the distance of the car? This is the goal: "1. your car must be powered by no more than 2 rubber bands. may be any size. 2. body of car may be made out of most common household materials. wheels may be previously manufactured, but body can not be. 3. may not launch or catapult car. must be self propelled." 

Question by bluefly1215   |  last reply


Quadcopter Build Check? Answered

I have recently researched and picked out parts for an entire quadcopter build. Would someone be able to tell me if all of these parts will be OK for a quadcopter build in terms of a.) if the parts will work together (I believe they will, but I am not 100% sure) and b.) if I will be able to do FPV with a Mobius Action Cam. Any and all help is appreciated, thank you in advance! (If I am missing anything important on the list please let me know also). Frame: I will be building one out of lightweight wood. Transmitter/Reciever: http://www.hobbyking.com/hobbyking/store/__9042__Hobby_King_2_4Ghz_6Ch_Tx_Rx_V2_Mode_2_.html Propellers: http://www.hobbyking.com/hobbyking/store/__39772__9x4_7_SF_Carbon_Fiber_Propellers_CW_and_CCW_Rotation_1_pair_.html Control Board: http://www.hobbyking.com/hobbyking/store/__17537__HobbyKing_Quadcopter_Control_Board.html Motors:  http://www.hobbyking.com/hobbyking/store/__39036__Turnigy_Multistar_2213_980Kv_14Pole_Multi_Rotor_Outrunner.html ESCs: http://www.hobbyking.com/hobbyking/store/uh_viewitem.asp?idproduct=27775 Battery: http://www.hobbyking.com/hobbyking/store/__16633__Turnigy_3000mAh_3S_30C_Lipo_Pack_US_Warehouse_.html Battery Charger:  http://www.hobbyking.com/hobbyking/store/__7028__Turnigy_Accucel_6_50W_6A_Balancer_Charger_w_accessories.html Power Distribution Board: http://www.hobbyking.com/hobbyking/store/__31223__Hobbyking_Multi_Rotor_Power_Distribution_Board_DIY_8_x_output_PCB_.html FPV Equipment: http://www.ebay.com/itm/5-8G-200mW-Video-Audio-AV-RC-5808-Wireless-Receiver-TS58200-Transmitter-for-FPV-/251413117397?pt=Radio_Control_Parts_Accessories&hash;=item3a8963b9d5

Question by Adum24   |  last reply


Could you make a ghetto mortar out of an iron pipe? Answered

Imagine that you take a four foot long iron pipe and cap one end of it. Near the capped end, you make reasonably sized exhaust holes. Just above said exhaust holes, there would be a few metallic protrusions that would stop a round from sinking to the bottom of the barrel. Aforementioned round shells would be made of smaller, thinner metal and filled with propellants. Means of ignition is still TBA. But if such barrel and rounds were constructed, could it effectively launch rounds long distances?

Question by Mr. Deeds   |  last reply


how to make a electric powered 1-2 seat trike hang glider on cheap?

What cheap materials would be best for making the wing (the frame and wing skin) and the trike part? also, i must know about the balancing of the 2. at some point i'd like to add 2 extra (adjustable) propellers to aid in hovering. Any info directed towards achieving this is greatly desired. Pics and detailed schematics are greatly desired. I'd like to be up and flying within 2-3 months maybe 4 if not sooner. Thanks.

Question by freenergyfuture   |  last reply


Can I use an old floppy disc motor to make a small wind turbine for my solor lights? or an old hard drive motor ?

I want to put some propellers on a PC fan motor or an old floppy drive motor and make free electricity, enough to charge my garden solar lights. I have tried connecting leds to an old printer motor and spinning it, the back emf lights the led for a second. spinning the other way lights the other led in reverse polarity to the first.... My problem is that the motor would continue to spin in the same direction in the wind...only generating electricity for a split second........ Pleeeaaaase help me!

Question by niceribs 


how can i use this mac g3 cd rom motor as a power generator?

hi guys im not a wizz at electronics at all, but i would like to use this mac g3 cdrom motor to create electric when spun i see it has some sort of coil inside to propell it around but if i put magnets on the out side could i create power? and also were could i put wires for the out put of power? here is some picks of what i have, ps all power im trying to creat is for leds of somthing not the entire house lol cheers for your help. (SORRY THE PICS ARE POOR)

Question by djmorgan27   |  last reply


Do you think this motor will work/?

So im planing on making an electric skateboard and i need help choosing a motor. I found a good one that i think will work and do just fine. Can you guys help me out? Also is a motors power based on whats? because i know (2) 2000 watt motors will propel a human but i dont know if that is based off watts or not.  this is the motor im looking at getting:  http://www.hobbyking.com/hobbyking/store/__29356__Dr_Mad_Thrust_1000kv_4600watt_90mm_EDF_Inrunner_8_10s_version_40mm_.html Also should i go for an inrunner or outrunner motor?  whats the difference 

Question by jnajmy   |  last reply


Anyone have blueprints or designs for a practical, full-size steam engine ?

A groups of friends and I (15 years old) are looking to re-create a steam engine to power a survey (we're thinking something along the lines of a steam-punk carriage powered by this steam engine)  we are designing. It does not have to be fast or very complex, just something to propel our vehicle forward. It must, though, be large enough to push at least three hundred pounds and operate for a good amount of time without needing to be refueled or tended to. After searching Instructables, I have found a ton of good steam engines, but they're all mini or meant for demonstrations. We need plans or ideas for a real, full-scale, functioning engine. Any advice, plans, or ideas someone has would be greatly appreciated!!!! Thank you all for your help, Carlinc   

Question by carlinc   |  last reply


Quadcopter using 12V battery and Wood Screwers

I’m currently attempting to rebuild the quadcopter demonstrated in the link below: https://www.youtube.com/watch?v=qa_x93JQhNM The materials I have are as follows: • SMAKN Buck and Boost Voltage Converter • 20 AWG Flexible 1007 Wire Electric wire 20-Gauge Copper Hook Up Wire • 2300KV 2204 Brushless Motor CW&CCW; • 12V 7 Amp EXP1270 Rechargeable Lead Acid Battery • Carbon Fiber Propeller • Digital Multimeter Attempt 1: We connected a motor to the 12V battery using clamped wire connects – there was a lot of sparking and the motor did not spin. Attempt 2: We connected 2 motors in series – connected the motors and the 12V battery to the buck boost convertor – which resulted in the battery smoking and the buck boost convertor burning out. Can you watch the video and explain to me the wiring aspect to the quadcopter - I believe I may be missing necessary wires such as a female insulated connector that connects to a terminal wire which connects to the 4 motors in series but I’m not sure.

Question by anthnymccld8   |  last reply


Need electrical help making small wind generated turbines to power LED lights?

For a grad school project, I want to create a series of small wind powered turbines that will power/glow LED lights.  I know it sounds simple, and conceptually all I need is a propeller to a small hobby motor wired to an LED.  All I am trying to do is create a series of little wind turbines to power little lights...so when it's windy they glow.    Like this toy, the Windmill Generator: http://www.amazon.com/gp/product/B0016PBH9Q?ie=UTF8&tag;=wwwsureshku0a-20&linkCode;=as2&camp;=1789&creative;=9325&creativeASIN;=B0016PBH9Q I have purchased 10 of these motors (link below), but need help selecting LED lights that would hopefully glow brighter when more power was applied (ie more wind energy). http://www.sciencekitstore.com/navigation/detail.asp?MySessionID=88-280260459&CatID;=96&id;=P56046 I am hoping the construction is as simple as the concept.  Any expertise would really great! Thanks! --Asa 

Question by asaeslocker   |  last reply


Coanda effect VTOL or "hovercraft" - making a working model

I am currently working on the design of an impeller driven lifting device utilising the Coanda effect. My 3D printer is of course a great help here but only useful to test the vacuum cleaner assembly that I salvaged for the motor and impeller part. So far it is just I am interesting to see myself instead of reading it on the net but I was wondering if any RC model makers out here would be interested too? I have no clue about the available brushless motors and controllers or how much extra weight for electronics, batteries and so on but could provide the 3D files and design tips if anyone would dare to create a working RC model. Unlike all the designs on Youtube no propeller is used for the lift! Those designs might still use the Coanda effect, or better adjust it's airflow, for the steering but the actual lift comes from a prop. An impeller as used in vacuum cleaner does not provide lift and is more the "real deal". The last real world project that I know of was the Avrocar that was tested during the cold war but never made it into production. Just though it might be an interesting project to build your own "flying saucer" :)

Topic by Downunder35m 


Record Solar Powered Flight

UK-built solar-powered plane has set an unofficial world endurance record for a flight by an unmanned aircraft.The Zephyr-6, as it is known, stayed aloft for more than three days, running through the night on batteries it had recharged in sunlight.The flight was a demonstration for the US military, which is looking for new types of technology to support its troops on the ground.Craft like Zephyr might make ideal platforms for reconnaissance.They could also be used to relay battlefield communications.Chris Kelleher, from UK defence and research firm QinetiQ, said Unmanned Aerial Vehicles (UAVs) offer advantages over traditional aircraft and even satellites."The principal advantage is persistence - that you would be there all the time," he told BBC News. "A satellite goes over the same part of the Earth twice a day - and one of those is at night - so it's only really getting a snapshot of activity. Zephyr would be watching all day." The latest flight was conducted at the US Army's Yuma Proving Ground in Arizona.The Zephyr flew non-stop for 82 hours, 37 minutes.That time beats the current official world record for unmanned flight set by the US robot plane Global Hawk - of 30 hours, 24 minutes - and even Zephyr's own previous best of 54 hours achieved last year.However, the Yuma mark remains "unofficial" because QinetiQ did not involve the FAI (Federation Aeronautique Internationale), the world air sports federation, which sanctions all record attempts.The US Department of Defense funded the demonstration flight under its Joint Capability Technology Demonstration (JCTD) programme. The 30kg Zephyr was guided by remote control to an operating altitude in excess of 18km (60,000ft), and then flown on autopilot and via satellite communication.It tested a communications payload weighing approximately 2kg.At first sight, the propeller-driven Zephyr looks to be just another model aircraft, and it is even launched by hand. But this "pilotless" vehicle with its 18-metre wingspan incorporates world-leading technologies.Its structure uses ultra-lightweight carbon-fibre material; and the plane flies on solar power generated by amorphous silicon solar arrays no thicker than sheets of paper. These are glued over the aircraft's wings.To get through the night, the propellers are powered from lithium-sulphur batteries which are topped up during the day."A lot of effort has gone into power storage and light-weighting the systems," explained Mr Kelleher. "Lithium sulphur is more than double the energy density of the best alternative technology which is lithium polymer batteries. The engineers from the Farnborough-based company are now collaborating with the American aerospace giant Boeing on a defence project codenamed Vulture.This would see the biggest plane in history take to the sky, powered by the sun and capable of carrying a 450-kilo (1,000lb) payload.US commanders say the design must be able to maintain its position over a particular spot on the Earth's surface uninterrupted for five years. QinetiQ is the public company that used to be the British Government's military research department, before they privatised it.BBC articleQinetiQ's page on Zephyr

Topic by Kiteman   |  last reply


30 minute DIY AM particle-acceleration

Last fall, I verified an initial relationship of resonance between two bifilar wound wires (of any length). The predictable sequence resonates at the following levels - 20 Hz, 30 Hz, 50 Hz (and all multiples of these 3 frequencies). I used a Parallax Propeller Board - with PGEN 2.0 software from Innovationshop in Germany.   This software allows for a waveform built of 32 stacked frequencies to be created and amplified.   I have used it to successfully break the bonds of distilled water - as one of my earlier videos shows 2 years ago. JL Naudin calls it a "GEGENE machine" - but it is a simple, tabletop, particle accelerator.  His results can be found here:::  http://jnaudin.free.fr/wfcbooster/indexen.htm One of my earlier videos from May 2013 - can be found at YouTube - I just want to show people how this works.  It is a 4 minute explanation of open-sourced Patent 512,340.:::   https://www.youtube.com/watch?v=HHxK1VWrXcM The materials:: 1 - 1800 watt induction cooktop (iron, copper, or 3-ply stainless cookware is required on these types of devices) 2.  50 feet of 14 AWG speaker wire 3.  2-10 count of 500-watt halogen lightbulbs. 4.  wire, solder & connectors for the wire-ends. 5.  1 stainless-steel HHO DC electrolyzer tank.  6.  Cooking Pan - or light fixture (to hold light bulbs). 7.  High Voltage diodes (500 Volts or higher)

Topic by jabel4   |  last reply


Jet engine turbines - how they work?

Hi, I know how jet engines work except for one aspect and for the purpose of this question I'll use http://en.wikipedia.org/wiki/Turbojet for the discussion so we're all picturing the same thing and because the illustration shows the engine quite simply. By looking at the picture, I understand that turbojet can't start itself, it needs 'spinning up' before it is ignited at which point it should sustain itself spinning and then provide thrust. I understand that because the turbine is spinning, the compressors at the front compress air into the combustion chamber, where fuel is injected and then ignited causing expansion, driving the rear turbines to drive the front compressor, and also providing thrust. What I don't understand is why the expansion in the combustion chamber isn't equally providing thrust in both forward and backward directions, and why it isn't acting on the compressors and causing them to be turbines just like at the rear of the engine.  What directs the expansion towards the back of the engine? and what stops half (or at least a large fraction) of it pushing back towards the front of the engine? I know rockets have an expansion but it's usually a tube with one end closed so all of the expansion is forced out of one end, but both ends are open on a jet engine? The question arose when I was looking at tin can turbines http://www.youtube.com/watch?v=2c1i_UIEsSM&feature;=related and I was thinking how I would build a small one myself but I couldn't visualise why the combustion isn't pressing against both the front and rear propeller cancelling any rotation out, and providing equal thrust in both directions? Thanks for your time!

Topic by arichardson   |  last reply


World's smallest (manned) helicopter ready for a spin.

Those of us who've been dreaming of cheap personal air travel in the Buck Rogers, sci-fi jet-pack mode should turn their eyes towards Vinci, Italy on May 25. That's when Gennai Yanagisawa, inventor of the tiny GEN H-4 personal helicopter, will be taking his lightweight 165-pound whirly-gig on a demonstration flight.Why Vinci? According to the 75-year-old Yanagisawa, "Since the concept of our helicopter came from Italy, I always wanted to take a flight in the birthplace of da Vinci." Indeed, Leonardo's famous notebook drawings from 1493 show an "ornithopter" with a screw-like rotor. Like da Vinci's pioneering design, Yanagisawa's GEN H-4 has no tail. Instead, twin counter-rotating propellers cancel out the torque that requires single-rotor helicopters to have a perpendicular tail rotor.The GEN H-4 personal helicopter is actually available for purchase now, though Yanagisawa's company (located in the Japanese city of Matsumoto) has so far sold only six (2 in the USA).The cost for one is a reasonable $58,250 and once airborne, the GEN H-4 can fly at a somewhat sedate speed of 31 mph - slow yes, but probably faster than rush hour traffic. Veni, vidi, volanti!It's the perfect commuter vehicle! Land on the roof of your office block, maybe it folds up, but certainly just push it into the corner to make space for your workmates to land. Sure, it only does 31mph, but it can go in a straight line, over the stationary traffic.Story on InventorSpot

Topic by Kiteman   |  last reply


Mac G3 password hacking?

I got a second-hand mac G3 for Christmas, from the sysadmin at my dad's office. Unfortunately, the sysadmin neglected to remove his accounts (and passwords), so as of yet it's impossible to get past the boot screen. Does anyone have any ideas about how I may crack the password or hack into the account... (changing the root password in single user mode doesn't work...) Oh, and by the way, it's running OS X of some sort, but since we can't log in, it's hard to know what cat it is. Help please!UPDATE:With the help of this site, we made an administrator account. We still don't know the master password, and there are a few untouchable files, but we can basically do whatever we want. The next challenge is to connect it to the internet...If you want to know how we got in, here's what we did:(1) we held down command (the propeller) and S as it booted --> this opened single-user mode, a command-line interface with root priveleges(2) instead of "rm"ing (removing), like the web site suggested, we "mv"ed (moved) /var/db/.AppleSetupDone to /var/db/.AppleSetupDone.old(3) we rebooted, and followed the instructions on the screenWhat did this do? It moved the file that told the computer that the computer was set up, so the computer ran the setup "wizard" like it was the first time the computer had ever been booted. After that, all we had to do was follow the instructions on the screen to set up an administrator (root) account. We also learned that the cat is panther, so we might be updating it to a newer version.Thanks for the help!

Topic by threecheersfornick   |  last reply