Speed radar traps information required

[thin wing]

In order to measure the speeds of my faster planes sports f5d and f5b I would like to obtain any usefull information on using
radar speed trap devices (if they are not crazy costs)

Has any one used or owned them and how usefull are they with model s


Is the radar beam very narrow and difficult to point or would it be suffencently wide beam to put on top of fixxed post so I can use while flying solo flying towards radar and does it possess memory or other features which could down load to my laptop HP 1000mghz

Can it be used to detect distance of craft and so be used to triger call at the far pylon so I could practice pylon f5d flying solo

My flying is normaly solo due to shift work and yes I know there are risks but its on farm land away from public and the farmer in the over looking farm has been briefed on what actions to take if I clobber myself (actualy seems to like watching the planes from a safe distance seen a few of my better crashes)

Any usefull info on costs specs URL experience in utilisation and any relevant info appreciated

Have never used one personaly but did see one fleetly for a speeding ticket(CAR not plane) and glow pylon speed event in france where obliging local cops helped out the modellers to get models speeds

If any electronic gurus know some other solutions which are capable of solving problem s outlined I am all ears

Using extra manpower and measured 100metres have reached 125mph in semi souped up f5d but its hard work to co ordinate this activity and takes several passes to cordinate team


David

[KillerWatt]

although you never really know how well a "gun"is gonna work with a given model, i'v read where the newest, all digital "DSP" guns have good range on small, sport type targets & will meassure & hold highest speed automaticly, for a bunch of $$$$........ you might be able to get a older KR 11 gun to do most of same with reduced range & less $$$ ... you can sometimes rent any of those & make sure it performs good enough before purchasing......... kw

[RMihara]

Hi David,

I've not seen a pylon race in person so could you please give me an idea as to the distance the aircraft is from a pylon, angle from it (from the horizontal plane), etc.?

I have an idea and it doesn't require a radar gun but I need some approximate numbers to check if it's feasible.

Please see the diagram below...



Regards,
Roger

[thin wing]

The rules and sizes of pylon courses vary from size and power plants of models countries etc but the theme is speed
Varios threads exist which can give exact information on Pylon rules in HIGH SPEED in EZONE

Couses for motor pylon are generarly triangle shaped

The type predominant in Europe is 2 legs 180metres and short leg 40 metres so total distance of each circuit is 0.4 kilometres

Typical 10 lap race with models doing ten laps in less than 90 seconds nowadays top crafts doing 10 laps in less than 70 seconds

At these speeds its very hard to describe the methods of flight the craft uses to go around pylon as blink blink it heading the other direction and another lap is done

Generally planes fly twice to three times higher than the pylon tower 20 to 40 feet up in the air at the far pylon marker but some pilots like me prefer the low down ten to twenty feet or lower section of the sky (more fun but taticaly not great as more easy to be boxxed in)

The pylon Model spend a lot of the time on its ear flying sidewards so angle of wing tips is close to 90 degrees approaching and turning at the pylon posts

Ultra high wing loading are the norm and this means 25% drops in speed coming out of the turns but micro seconds later back to full speed

This is not your large RENO craft wide aproaches to turn but more your Guided missle turn turn turn race where snap turns are the style of flying and off centre run lines out of turns can result in valuable micro seconds lost flipping wings back and forth to reralign the craft

Not a lot of modern electronics I can think of can track these things as they are very small 40 inch wing spans with speeds in excess of 140 MPH

The main problem for pylon racing is that the far end pylon or apex (pilot are near to the other small base line) is that to run a race it is nessary to have a victim with a flag raise a flag when the plane has passed the far pylon and a copilot standing beside pilot call out turn when model has passed the pylon to recommence the return run
This leaves pilot free to fly plane (missle) and fight for good tacktical position in the four plane packs

This means that pylon racing requires a lot of manpower to run a single or multible race event

Having seen tennis and other sports which adopted electronic sensors to track ball speeds in exceess of 100mph thought it might be interesting to try some ideas out

As an electronic teck myself suspect GPS systems are still to big to stuff into 40 inch models and to inacurrate to supply plus or minus 1 foot tolences to do the job

I am also checking out the idea of rigging out my laptop with web cam to look at approching model through simple sights or with some simple type of sight recognition progamand to illumate a light or sound relay speaker system with wire relay to beep a tone when model has passed far pylon marker

Suspect speed trap radar coupled to laptop would be better solution but have a suspicion these radar prices are too high

Lazer suspect not able to detect small models especialy in good sunlight

welcome any interestig ideas

David

[RMihara]

Hi David,

Wow that's just plain smoking along there. I suppose you'ld NEVER want a radio glitch to occur at those speeds...

Okay so approximately what are the typical fuselage dimensions? I'm trying to get a handle on how long (or fast) a planes profile would be present in say a 1-2 foot wide 'zone'.

Roger

[thin wing]

Electric craft vary s400 type with smaller craft and smaller pylon craft are usually 750mm to 900mm wing 28 inch to 36 inch wiing with super thin fuse to hold 6 to 8 AA sized nicad nimh often rear half of fuse is carbon boom speeds usually less than 100mph except for top class stuff sports stuff 50 to 60 mph

F5d class are sometimes slightly smaller than biggest s400 but have much larger battery sub C 6 to 8 nicads pulling 70 plus amps and engines often 600 sized or brushless 500 or quality brushed 600
Front and midlle of fuse larger but wings are typicaly 900 mm plus to 1200 mm 36 inch to 48 inch and in the straights have been radared at over 140 mph but many sports types in the low 100 mph

(best is to imagine a 15 glow sized craft with 25 to 90 glow engine power to get idea of the size and power of the planes not very big)


The routes the planes take to get around the pylons vary considerably to do with wind,planes pilots etc

Some pilots will use straight line quick turns close to pylons with larger reduction in speeds coming out of turn to other pilots who take longer wider routes to reduce speed loss in the turns and also will change routes teckniques in flight to avoid collisions from four equaly matched planes grouping too much at turns etc.

The varables that dictate you pass a pylon one time at 3 feet high and three feet out and the next time at fivty feet high and 50 feet past pylon are so numerous its hard even for the human to observe one pylon craft competor no X has passed the pylon and signal this event

I am hoping with the change from brain dead slow windows XP on my 1000mghz laptop to much faster linux 7 and coupled to a visual system or radar system that it might be possibe to signal this event and also use this information to get speeds coming out of the long staights

However as all money spent on measuring could be better spent on getting latest go go plane or hotter motor the requirment to stay in a sensible budget and accept a drop in quality in information would be the balancing factors so web cam is much more interesting than fancy priced vidio or radar

However as I have no real info to work from it is possible some type of reasonable priced radar exists as second hand or kit etc but I dont know the charicteristics of these radar units to judge it potensal to be usefull or not

Also other methods of electronics exist that may be able to do some or all these jobs possibly LAZER or field affect electronics etc

All ideas accepted preferably re -using some ready made reasonably priced well tested device from some other industry with some minor modifications to re -use in this situation and preferably ground based so as not to interfer with models flying qualities

GPS units suffer from cost $ weight on board craft and size problems but are a possible solution as costs weight and sizes diminish ( would happly strap my GPS watch onto fuse if it cost 100$ and weight was 50 grams with accuracy plus minus one foot):D :D :D

An on board speed indicator is less usefull as it will not supply ground speed info and no information that I can foresee to indicate turn possition

Lazer would I imagine would be inconsistant due to reflectivity qualities of model and sunlight problems

Radar I suspect would also be deficent with pylons small profile head on and beam width but not sure of specs of Radar

Might be cheaper and easier to train a monkey with a banana to press button when model passes over head:D :D :D



Like I said all good ideas accepted

Fly low and fast and churn up the dust

David :D :D :D

[polamnus]

I don't know for sure, but the first thing that came to my mind was a Paintball Chronograph. They sell these units for ~$100 and while they probably wouldn't work out-of-the-box for this application, you could modify one pretty easily. Typically there's two optical sensors that you fire the gun accross. Like I said, I've got no idea if this would suit your needs, but I'd imagine if you sat one of these units on a table and flew low overtop of it, I'd imagine you'd get a pretty decent speed reading, probably in feet per second, as that's what the guns are clocked in at.

Google for "Paintball Chronograph" for more info.

Hope this helps!

Best to all,
Pol

[thin wing]

Never would have considered paint ball thanks

There are many gadgets in the world and hopefuly paint ball might be the solution

I will report back later after viewing the site fingers crossed

Fly low and fast and paint ball it

David in Ireland:D :D :D

[thin wing]

Looked at loads of sites with paint ball and also standard guns .22 calabre etc

The general theme is they can measure a bullet or paint ball within very narrow limits

Without going into the specs of light sensors and doppler types the only vauqe possibility is the doppler types
The best looking candidate is the type which sits on the ground and you fire the paint ball over it so it reads the speed as the ball flys away from it

However the specs suggest it is very low power type (powerfull radar signals are harmfull like micro wave ovens ) and so a serious question exists would it be able to detect the an object passing overhead at some thirty feet altitude

If some user of paint ball doppler type chronograph who would be willing to repeatly fly his parkfly over his paint ball chronograph doppler detector at various alltitudes 10ft, 20 ft, 30ft ,and could verify if the machine was able to

1)
Detect the presence of the plane consistintly at which altitudes then the device could be used to verify the turning point for the far pylon

2)
Will the machine have a better detection rate if plane flys towards or side onto machine

3) will the machine give out a negitive no if flown towards machine and what speeds does it generally show

I suspect from the information gathered so far on specs of these paint ball dopller chronograph machines the range is very small in the order of some five feet or less

A test with a football lobbed or kicked over chronograph would also give some information

Possibly some electronic guru may know some way to increase range by something simple like increasing voltage from typical 9volt dry cell to 12 or 18volts without frying system or aluminum reflector to amplifly beam

I have checked a huge amount of sites to see what the specs on police type radar units and they sure are impressive

They can nail the speed of your car from one mile even as you pass out the slow truck (wont be speeding again) thats with these new narrow beam LAZER units but exact details on other type k band x band and other older types seem to be difficult to get and nowhere have I seen any cost prices in dollors or other currencies

Does anybody have some good sites to check and have some ball park cost prices and ball park spec details

So far all indications are the trained monkeys got the edge on all the high teck solutions :D :D :D

Better start surfing bulk purchacing of bananas

David in Ireland :D :D :D