Telemetry - do you use it? What do you think of it?

[PatMc]

Posted by Eric Bray on 29/03/2011 12:12:34:

From the slope-soaring point of view (obviously my own!) I wouldn't care to take my eyes off the model, to change focus and look at a little screen, then look back at the model again. In that half-second or so, all kinds of nasty things could be happening!

A low battery alarm from the model could be handy, but also a model-finder function, where an arrow on the tx screen points to the model - handy when you have had a sudden arrival in trees, tall crops, etc!

The 'beeper in the model' gadget helps, but in rustling grass or whistling trees, in a wind, and you are struggling.

Of course - both of these assume the battery hasn't become disconnected when the model decelerated suddenly!

AFAIK Frsky telemetry has audible low batt & low signal alarms. I read about someone who used the LSA to find a lost model by shielding the aerial with has body (He may have also switched to F/S range check) & used this as a direction finder.

 

 

[birdy]

TBH I do not really see the point of telemetry for the things I fly; I am of the oppinion that you should know when you are about to fall out the sky (can't anyone else "feel" it?) and you don't need telemetry to tell you when you lipo is about to run out of juice. I use one of these things with a very bright LED that flashes at a pre-set voltage. I also think that in the applications it would be most useful (ie. high value models or high performance models - dead stick in a trainer isn't much of a problem) it is also most dangerous - taking your eyes off the model for long enough to take in the information takes around a second, and a fast moving model can do alot in that time.

The idea of a fuel senser is good, but if you can do that, why can't you just put a flashing light on the outside of a model?

 

On the plus side, telemetry is pretty cool, but I personally see it as an unneeded cost.

[Chris Bott - Moderator]

If you're flying something high value or high performance then its a pretty good idea to have a spotter alongside who could also read the telemetry if needed.

 

I fly with A123 batteries, they stay giving full power until they are empty, so no, I don't "feel" it dropping off. So far I fly to a timer and land with some to spare. But knowing what I'd used or have left would be progress.

 

 

[PatMc]

I wouldn't use a visual display very much, particularly when flying thermal gliders as they are the models that fly furthest from the pilot & can be difficult to re-locate if you look away for a couple of seconds. But audible alarms could be very useful for range & Rx battery power warnings.

 

Birdy, if you've had 4 or 5 power bursts with an E glider then hit a thermal you can be in a dilemma wondering if there's enough left in the battery to continue gliding or if the motor runs have used up too much of the battery capacity.

[Alan Bahia]

Going straight to the point why I live the system and how I'm using it.

 

1. Flying a bigger plane where servos drain quite a lot from the batteries in flight it is usefull to have my transmitter vibrating and have a sound to alert me to land save. So I don't need to be looking the screen.

 

2. I can check the batteries level before flying and have a sort of idea if safety or not.

 

3. I can also, check my ignition level of battery as my large aerobatic plane with somke system and so on i'ts a bit heavy and would not glide in for a deadstick landing.... we have a sort runway and not good to land around realy! So, I have a alarm here too. Make things safe to everyone!

 

4. I can read the engine temperature and know when hot enough to use my smoke!!! Would make a difference without it... off course not! but helps you to identify when hot enough to also work on needle valvule.

 

5. Can read RPM, work on performance, best prop etc. You can see the screen as you don't need to be flying...

 

Now, I'm looking forward for additinal devices such as telemetry to read fuel level.

 

 

Why not to make things safer for pilots and people around? Am I a sort of geek person...you can say yes!

 

At the moment I'm the only one in the club with DX8 and I'm loving it!

 

 

Last week we have had a crash with someone flying 35mhz... wrong plane on the transmitter!!! all controls inverted... to confident...did not check controls before flying..... accident happens... loads people talking.... etc.... DX8 or my previous DX7... no problems!

 

 

There you go... I'm in favor of this growing technology!

 

 

happy landigs!

[Steven Buckingham]

I'm a returning flyer and have just got myself a Hitec Optic 6 as a starter tx partly because HiTec seem to be a step ahead on the telemetry front? I think the opportunities of telemetry are great particularly the idea of a variometer on a glider!

 

To start with I'm looking to make use of the basic functionality included in the kit to set up the low battery warning for a 3 cell lipo. I got the HPP 22 setup eventually (v.poor instructions included, but a trip to http://hitecrcd.co.kr/tester/hpp_22.htm for the .exe got it functioning, and why couldn't they build it direct into the tx?)

 

Can anyone advise what the low battery warning should be set at for a 3 cell Lipo? I'm pretty conservative with my air time but a backup doesn't do any harm!

 

Thanks

[Spice Cat]

Pardon me for asking as I don't know much about this telly whatsit stuff, but is this system capable of monitoring all the functions on board a model, capable of storing that information in a downloadable form and effectively becoming a "Black Box". Essentially, could it record the status of received signal strength at the rx end??

If so, this could make the after crash investigation (I'm doing a few of those at present) so much simpler. Could it also provide a second by second readout of the status of received signal strength?

Just musing.....

[David Ashby - Moderator]

Spice - some already have signal strength telemetry, Multiplex as standard for one.

 

 

 

 

 

[Spice Cat]

Funnily enough I was looking at the Wealdon open day and can't remember seeing anyone with a Multiplex set and only seen one elsewhere. They don't seem to be in the mainstream.

I suppose you could have a Tx that spoke to you like some systems on board full size aircraft, but I would not opt for the female voice. I don't fancy being nagged by a computorised one as well as the real thing.

 

 

[Tim Mackey]

Posted by Steven Buckingham on 29/07/2011 01:16:43:

I'm a returning flyer and have just got myself a Hitec Optic 6 as a starter tx partly because HiTec seem to be a step ahead on the telemetry front? I think the opportunities of telemetry are great particularly the idea of a variometer on a glider!

 

To start with I'm looking to make use of the basic functionality included in the kit to set up the low battery warning for a 3 cell lipo. I got the HPP 22 setup eventually (v.poor instructions included, but a trip to http://hitecrcd.co.kr/tester/hpp_22.htm for the .exe got it functioning, and why couldn't they build it direct into the tx?)

 

Can anyone advise what the low battery warning should be set at for a 3 cell Lipo? I'm pretty conservative with my air time but a backup doesn't do any harm!

 

Thanks

 

 

if the battery you want to monitor is in the model and powering the motor, then set the LV warning at around 8.5V.

If its the tx your talking about, then set it for approx 10.v

[Tim Mackey]

Posted by Spice Cat on 29/07/2011 06:27:10:

Pardon me for asking as I don't know much about this telly whatsit stuff, but is this system capable of monitoring all the functions on board a model, capable of storing that information in a downloadable form and effectively becoming a "Black Box". Essentially, could it record the status of received signal strength at the rx end??

If so, this could make the after crash investigation (I'm doing a few of those at present) so much simpler. Could it also provide a second by second readout of the status of received signal strength?

Just musing.....

 

The eagle tree data logger is a standalone onboard unit which can monitor, and record data such as RPM, current, voltage, servo consumption, throttle position, watts, altitude, and so on ( not signal though ). It can even record your exact flying pattern, and display it back in google earth style map display.

This is a typical "dashboard" display from the Eagle Tree logger.

Click for bigger picture.

 

The Spektrum DX8 has telemetry system with a vibrating alert to warn you of battery levels etc, and other high end spektrum receivers can also record signal data which can be displayed in a basic sort of way after the flight.

[Tim Mackey]

Another eagle tree screengrab snapshot from an inflight recording - this time showing throttle position, servo current consumption and temperature of ESC etc.

Obviously, on the actual computer, the play button allows a playback of the whole flight, with real time display of the data.

[ken anderson.]

one of our club members has some equip that he has sending back info to him on the ground....... when we are standing in the pilots box... it can be a bit annoying listening to it it 'bleeping' all the time......every second or so......

 

ken anderson ne.1.

[Danny Fenton]

We had somebody that had a telemetry variometer, telling him when he was in lift or sink with his glider. Wish he had an earpiece! it is indeed irritating, I thought gliding was supposed to be silent flight?

You can set the jeti to bleep, but I much prefer to have a caller/spotter look at the numbers when I fly. Usually Chris, Thx mate

According to John at Puffin, the new Jeti DC16 is now expected in September, this has full telemetry built in.

[Erfolg]

At present they are all to expensive for me.

 

I keep an eye on the Quantum system as sold by HK. To date the system is a far cry from Eagle Tree in the products capabilities.

 

I guess I am looking for what is called glider capability, with some additional information on power usage or volts. Much of the info wanted for examination later. Possibly only a variometer, in real time.

[Steve Hargreaves - Moderator]

I think Telemetry will be the next big thing. I don't have it at the moment but can see the advantages.

 

Obviously cost is a huge factor...if its cheap enough then it could be incorporated into every model & as we all know technology has a habit of getting cheaper....(who'd have thought, 30 years ago we'd all own several receivers & dozens of servos & have several models all flight ready at any one time......in t' olden days you had to swap the radio gear from one model to the next.....why I remember one time....continued on page 94)

 

For me one issue that needs solving is how this information is presented to the pilot....right now it's hard enough just looking down at my timer but if I had Fuel Level/Battey capacity, Rx battery voltage, height, airspeed VSI etc etc I'd never cope!!! How would that work? Different tone for each parameter.....? Voice warnings?

 

Imagine a group of flyers in the Pilots box...all with Telemetry warnings.....

 

"Is that your low fuel warning Fred?"

 

"Can't be...I've only just taken off...I think it might be Charlies Rx battery"

 

"Not me" says Charlie "Isn't it Mikes stall warning...?"

 

Or even worse....voice prompts.....

 

"Fuel Ok....fuel OK.....look out, you're going too slow.....climbing...climbing....oops you've stalled....watch out now...you're approaching VNE....TOO FAST, TOO FAST....watch your Rx battery...its down to 4.9 volts....."

 

Aaarrgghhh it would be like going for a drive with Mrs H.

 

Personally my biggest worry is that it will remove my last excuse for my rubbish landings.....after all if I have an ASI then how will I excuse stalling in from two feet....AGAIN!!!

[Bob Cotsford]

I use battery warnings and find them helpful on electrics to get the most out of LiPos, and as an emergency warning for IC batteries but other than that I find it a distraction. A speech synthesizer through an earpiece would be useful but only if it was selective of what info was passed on.

For example, low RSSI (signal strength) warnings are only usefull if it warns of extremes, but the default FrSky setting just indicates that you are the other side of the field, much to cautious a setting.

I did play with a vario in a Cularis, but it was a pain as I couldn't switch it off when not seeking thermals, so climb outs and aerobatics were accompanied by miscellaneous beeps and squeeks.

[Lee Smalley]

not really interested in it, i bought my tx knowing it would never support it, and that suited me, i do not fly a lot of electric and therfore its not of any help to me, i can see it being a big help to the electric fliers out there or the really tecchie crowd who like to play with these things, all i ask is that if you have a vario fitted please dont stand next to me flying, i can not think of anything worse than when the suns high in the sky,... my glider is even higher .... the birds and floating around... and all is well with the world... and then..... BEEP..BEEP ...BEEP as some planks vario kicks in, there would be a bop on the nose for the offender there !!!

[Tim Mackey]

Cant say it does much for me either TBH. I also found it extremely difficult to readily see the data display - and found my self looking at the screen for far too long. I actually prefer the eagle tree system, when I can bring the unit back home, and sit and analyze the data I want in the comfort of the armchair. The only "telemetry" I will likely use on my new DX8 is the vibrator - steady now......

[Danny Fenton]

With the Jeti unit you can look back through the data when you land, I often do this to see the max current I hit during the flight, lowest voltages, and actual flight duration etc. Not as all encompassing as the Eagletree granted but the Eagletree isn't live. I set a pack consumption alert at roughly 500mAh before my critical voltage and it makes a single bleep. I have never heard it while flying as my spotter reads the numbers. I do not look down at the Tx at all.

If you are flying something that can just go dead stick and glide down they will be of little interest but if you are flying a 1000 plus hour model It is very re-assuring to know exactly how much fuel is in the tank, irrespective of the wind conditions. A small price to pay in comparison.

 

As an aside I taxied out to fly once and got to the end of the runway and the Jeti started squeeling like crazy. Upon investigation the Rx signal was low on both aerials. You guessed it, no aerial fitted to the TX module..... a stark reminder that even when we are vigilant it just takes a slight distraction during your pre flight checks and things get forgotten. Roll on the DC16 which is 2.4 as std.

[Steve Houghton]

I made this comment in another thread about the Jeti system, but it bears repeating:

 

The ideal solution to viewing telemetry data - how about a Head Up Display for modellers?

 

It could be built into a transparent visor attached to your flying cap and dangling in front of your eyes. All data instantly visible on the visor without taking your eyes off the model. It would include UV protection (sunglasses!) and auto-dimming to account for changes in ambient light.

 

Slope soarers would find the added protection from the wind invaluable, and could instantly see their height, variometer, and airframe stress for those doing DS!

 

 

[Danny Fenton]

Interesting idea Steve, I think it would then get very expensive?

[Kozmyk]

 

I don't know about telemetry being "the next big thing" it's here already.

Clearly it's going to spread further through the hobby.

 

I've got the Quanum system running next to my Spektrum DX7.

What I do like about the Quanum is the individual lipo cell voltage display.

I haven't had a cell go bad in flight yet but if I do I hope to get prior warning via that multi cell monitoring.

I'm surprised the other manufacturers haven't included that facility in their telemetry offerings.

 

A useful wrinkle for actually seeing the info from your telemetry system without taking your eyes off the model would be to organise some form of HUD.

A variation on a theme from the world of FPV could do it .

A pair of "Fat Shark" type sunglasses would do the trick except you'd be able to see through them rather than at a pair of mini screens. Monochrome LCDs would do it.

I don't know how you'd manage the focal length though.

I'm sure there'd be a way, the principle works for camera viewfinders, gunsights and range finders.

 

Regarding beeping indicators. I think there's a case for them being put out on earphones instead of sounders/speakers, beeps or voice alerts.

 

Ha ha ... I went away to think about this and Steve Houghton has beaten me to it.

[Steve Houghton]

Hi Kozmyk,

Welcome to the Great Minds Club!

 

Danny, some people just love their gadgets, whatever the cost! Isn't that why we fly models?

 

Edited By Steve Houghton on 29/07/2011 13:43:28

[Wingman]

Telemetry seems like a nice idea particularly with regards to battery voltage but I think that for us model flyers the bees knees of telemetry would be a stall warning device. It would be really good to get some sort of audible warning of approaching stall as we are usually too close to the ground to get the nose down successfully when it happens - maybe some sort of hot-wire flow sensor mounted on the wing top surface?? What do the engineers on here think?