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

[Richard Sharman]

Data could be logged either in the plane (needs another unit to plug into the TM1000, I suppose), or from the Tx (and the SD card sounds a good candidate).

 

Does the PowerBox do logging ?

 

What about an iPod connected to the STi interface unit ?

I'm not familiar with any of this.

[Erfolg]

Personally with respect to Telemetry, I want to be a user. I do not want to have any specific scientific or computational skills. I will want to plug and use.

 

Any data which is downloaded for evaluation, will need to be easily done, friendly, downloaded via a common data transfer lead,or maybe WiFi. An interface which has a simple button menu, to do what I want, intuitive in operation.

 

For real time data, again I am hoping for a menu of methods, be it audible (earplug or speaker), Display to a clear visual display, be it a screen, or a transparent visor type.

 

With respect to sensors/transducers, again they will need to be small, light, non critical with respect to installation, very robust and low cost.

 

This is my wish list. I believe there is a long way to go, before, the majority of adopters will see Telemetry as a must have, or just, would like.

 

There does tend to be a gulf between the early adopters and the mass market. Early adopters are more probably going to be techies, rather than us later adopters.

 

At present i am hoping that you guys will drive the market towards where I would like to see it.

 

Having worked (payed the bills) for some of Richards colleges at Southampton Uni, developing, a non invasive flow measurements system, it can take time and effort to get a user friendly system, from the techies. The question for me is, can I wait 5-10 years for the technology and systems to mature, will others, to something that works to my wants? As much as what is now avant-garde, cutting edge, will soon be past the sell by date, consigned to the attic

[Myron Beaumont]

I'm beginning to wonder why I should enjoy flying on my own so much when others have so many probs .Especially with the couple of basic combos I recently bought for next to nothing ( 2.4 as well ! ) involving altering lengths of servo to surface connections I have a good idea as to when to recharge whatever it is and am not obsessed with knowing what is happening up there whilst I;m flying (I can see a stall and learn not what to do I don't ever intend to spend my flying time looking or even glancing at a screen because I enjoy the whole point of modelling ie Being a pilot .. Having said that ,I do appreciate that for you glider peeps it is very nice to know about whether you are in lift or not being so high up . .I also think that it is helpful for peeps that can't work how long they can fly for .Personally ,I've never had a problem with it -BUT it seems these days to be one of the most talked about topics .these so called problems Is it basically meant for us "Joe public" to buy the latest innovation or what ? I enjoy what I've spent time on creating something and flying it and only I did it .

Where's that coat ?

[Erfolg]

We probably thinking along similar lines Myron.

 

I do fly gliders about 50% of the time and as you say variometers would be immediately useful.

 

With respect other data, Time will tell what really is useful to us everyday flyers, I would expect that it will often depend on the type of model.

 

Competitive gliders will probably be interested in graphs of height relative to time. There may be an interest in speed, particularly the FB3 types(multi task type). Although in competition I would expect that the prohibition of variometers will continue.

 

I cannot begin to predict what a scale modeller would want know and I would think that a similar situation exists for other groups.

 

We can see that manufactures are having an educated guess of what modellers will want and what is immediately easily delivered. It will be the market that eventually determines what is useful and how the majority will want it presented.

 

We are living in a world that at the moment is changing incredibly quickly with respect to computer type equipment. In my youth, the computer filled a very large room. At the time IBM predicted that there would be very few computers in the world, but would be colossal mainframes with dumb terminals. I remember the first PET, that my employer bought for the section. I went out and bought a Sinclair Spectrum, then a Commodore, then an Amiga. these are all in the attic, with tape and disc drives. I have had four different printers. This is the third PC, I have a portable which is now under specked. Each change has been better, most step forward have come, with some pundits saying, "is this a step forward". With hindsight, each product, piece of software has been much better. There have been developments that very few foresaw, from the net, online music downloads, the vast majority of software packages. I expect something similar will happen with Telemetry. Our attics will be bulging with old Telemetry gear.

 

So where we are going, I have not got a clue, so I think. Yet again with hindsight, I do feel we all know where the steps might be. As I remember (as one of the few in the 60's who can) when leaving the computer desk, one morning, when my punch cards yet again failed to compile, there must be a better way than this. So it will be with telemetry. The complaints with respect to looking down to a small LCD to read data, will be addressed and solved. If beeps are less than the complete solution, a better way will be developed to communicate. Although I am not completely sure that all the solutions will come quickly, as I still need a keyboard to write this and I am less than proficient with the dam thing, and so many predicted the demise of the key board for the last 40 years.

[Richard Sharman]

Posted by Erfolg on 13/09/2011 01:07:10: ......there must be a better way than this. So it will be with telemetry.......

 

Dear Carl, So nice to read your thoughtful posts ! Yes, and No, is I think the answer. Two points can be made:

(1) telemetry without logging is only half the story. EagleTree has both and is a usable system, but Spectrum only has telemetry which renders it an interesting novelty so far.

(2) the "luddites" will always say that what we have is fine, and nothing more is needed, but history has tended to disprove that - we "need" things now that we previously didn't even know existed.

 

Perhaps I can suggest one area where every (power) flyer would agree, if they stopped to consider: "how long is my flight going to last?".

 

With an I.C. engine at a steady-ish throttle and normal flying every flight tends to last the same length of time, so the clock is a good guide to when I should think about landing. But what if I set the mixture a bit rich in the winter, what if I am held on the flight line before taking off, what if my pump didn't completely fill the tank, etc, etc? Just depending on time is not good enough. But a proper fuel gauge sensor and telemetry system with warning is not yet available in mainstream products - perhaps it should be?

 

The situation is the same for electric - I tend to use the throttle much more actively with electric motors to get a greater range of performance (using the ability to stop and restart). And the cost of getting it wrong is higher: if I lose power because of battery exhaustion in my EDF jets they are likely to fall out of the sky, whereas most of my i.c. planes will do a semblance of a glide and a successful dead-stick landing. So, an electric "fuel meter" would be useful, rather than just depend on the clock and what happened last time. But an airborne watt meter etc is not mainstream (although easily implemented) - perhaps it should be ?

 

regards, Richard

Edited By Richard Sharman on 13/09/2011 10:59:20

[Martin Harris - Moderator]

 

The situation is the same for electric - I tend to use the throttle much more actively with electric motors to get a greater range of performance (using the ability to stop and restart). And the cost of getting it wrong is higher: if I lose power because of battery exhaustion in my EDF jets they are likely to fall out of the sky, whereas most of my i.c. planes will do a semblance of a glide and a successful dead-stick landing. So, an electric "fuel meter" would be useful, rather than just depend on the clock and what happened last time. But an airborne watt meter etc is not mainstream (although easily implemented) - perhaps it should be ?

 

I can't answer for other systems but the Jeti system has had what are effectively airborne Wattmeters available since launch which display instantaneous current, pack voltage and power consumed with user settable warnings of parameters out of limits.

 

Co-incidentally, I bought one last week and am awaiting the chance to test it in anger as I am very interested in the amount of "unloading" that occurs in the air, having bought a second hand model which has been flown successfully but seems to draw well over the rated motor current on a static test.

 

I have enjoyed the security of getting real time confirmation of the received signal strength in my IC models for the last couple of years and also use the vario module in an EP glider - the only real criticism is that an earphone socket would be useful to avoid annoyance on a busy flightline.

 

I have been tempted to invest in the airspeed indicator module but I think its use would be more for academic interest and tend to rely on attitude to guage airspeed on the approach. Anywhere else, I'm either stalling deliberately (flicks, spins etc.) or making a rapid error such as pulling a combat model round a turn too quickly where the warning would probably come milliseconds before the stall...

Edited By Martin Harris on 13/09/2011 12:27:53

[Erfolg]

I think it is a Jeti system that turns up at our field from time to time.

 

I know that has been used regularly to determine the the height cut off on the motor (gliding).

 

The more obvious usage has been after flight analysis of heights reached and speed.

 

I seem to remember that the revs and amps have been compared on static test and on launch. I do remember how emphatic the discussion that the unloading on launch was much lower than anticipated.

 

At the moment all the early adopters I know, within the club, are competitive flyers. For this group, understanding the actual performance parameters of a model potentially provide the edge that a competitor is always seeking.

 

I can see the benefit of knowing the actual power remaining in a battery for an electric DF. I would anticipate, that this telemetry will become standard for all of this type.

 

At a personal level, I favour the stall warning as a like to have. Be it by speed/velocity equated to the stall.

 

I do keep an eye on what is available, quite enviously, not as yet quite tempted as what I think I want, is a little to pricey for me at the moment. Eagle Tree to expensive, Quantom seems to do very little,although cheap (or is that expensive, if it does little).

 

I personally like the dashboard type product, as it is independent of Tx. Inbuilt systems can be poor as the on-board Mercedes sat nav, Where you are stuck with it. Also when i went to the USA this year I was able to stick my portable sat nav in the hire car, it cost me about £30 for a USA update. I would like this flexibility in Telemetry.

 

It would be interesting to know, how widespread are telemetry systems in modelling, and which are the systems, accessories modules/transducers that are being used and for what.

 

I was thinking a little earlier about my daughter and the son-in -law. They seem to typify a great divide. My daughter has a I-Phone, the styling is excellent, its performance is impressive, she also now has a I-Pad, and all of the aforesaid can be said of it. Pretty impressive. The sin-in-law has some other phone, seems better in performance, in what it can do, looks like a typical Far Eastern product, he also has a tablet of some sort. Now the son-in-law tells you all about the Android operating system, the processor speed, transfer rates and lots of things, which these days leave me cold. Apple products are above all are stylish (impressively so), they work ok, the buyer is essentially an early adopter, who is non techie. Whatever the son-in-law has, is technically possibly better (although stylistically ordinary) and is for those who are early adopters, who are obsessed with techie things. My daughter is quite happy having to send the I-phone back to Apple as the battery had failed and buy all her apps (whatever they are). Where as the son-in-law, sees these things as unacceptable. I guess i am an Apple type of modeller, otherwise known as a Futaba user. But who longs for the flexibility of the competitors, such as Spektrum.

[Richard Sharman]

Well, what can one say? Progress breeds progress, and each generation takes the accumulated achievements of mankind as "given" and moves on.

 

Personally, I use telemetry because I want to know specific things about the performance of the model. Simple things, like: how fast is it flying? is my battery about to give out or can I do one more circuit before landing ? and so on. The sort of things the pilot of a fullsize plane needs to know, and gets by reading his instruments. Unfortunately most of the things we would like to know are too difficult to measure, so we just trust to luck like we always do.

 

Does anyone know if/when Spectrum are going to offer a logger (either in the model, or on the ground) to save the data being downloaded ? That would be my number on request.

[Chris Bott - Moderator]

My understanding Richard is that Spektrum logging is/will be available in the (much) more expensive transmitter when that comes out, but is unlikely to ever be available in the DX8.

[Richard Sharman]

Yes, I rather suspected that might be the case. Spectrum would have to write the log to the SD card, and they probably haven't put fast enough chips in the DX8.

 

However, I've solved my problem by using an EagleTree logger in the model, in conjunction with the DX8 downlink telemetry. So, to some extent, I amd getting the best of both worlds: I can log everything I can think of in the model, and at the same time I get a download of certain key parameters (such as battery voltage) which are programmed to give me audible alerts if something goes wrong.

 

So now I can just take off and fly until some alert sounds (hopefully just the timer) at which point I land. Then I can look at the log in detail and cogitate over the result at my leisure. Bliss! of a kind.

[Keith Emerson]

I have a DX8 and have been using the main battery monitor / alarm for my EDFs. Recently I've added the air speed & altitude sensor. I agree that there is no way I would use the display during flight as a quick glance down whilst doing 120mph would surely end in disaster. The Spektrum does have the facility for viewing min and max values for all sensors fitted after the flight. This is useful purely from an academic point of view i.e. how high and how fast and a practical point of view for reviewing Rx and main pack minimum voltages.

On a slightly non-related topic, after I fitted the telemetry module to my AR8000 Rx fitted to a Habu 32DF I lost control of the plane after selecting full flaps. Some time later after rebuilding I found that intermittently the Rx would reset when selecting full flaps, this included cycling the u/c and sending the elevator servos past their end points! Despite the ESC BEC being operated well within its current capability and no binding etc on the servos the Rx was seeing a momentary drop of voltage causing a reset, I believe that adding the telemetry module was the straw that broke the camel's back. I've now fitted a separate BEC set at 6V and not had a problem. The telemetry now reassures me that the Rx voltage never gets near the minimum voltage for the Rx. So Spektrum telemetry users beware and go for a separate rx battery or independant BEC.

 

Finally I'm hoping that Spektrum will bring out a dongle for a laptop (like the hitec one) so that I can view and record whole flight data on the laptop. If they can do a separate dongle for the iphone then I'm sure that it wouldn't be a big problem to adapt it for a USB port on a laptop (unless of course they want to promote sales of their higher end Txs!)

 

Overall I find telemetry useful and fun

 

Keith Emerson

[Richard Sharman]

I second that, Keith ! A dongle to record straight to laptop would be great - does anyone know if there is a chance of this happening someday soon ?

 

I thought the story about the loss of the Habu was rather shocking - and quite a salutary caution ! I load up my ESC BEC with gay abandon, and fortunately haven't ever had anything go wrong that I could attribute to that, but it could happen. Most of my failures recently have been more battery related problems, where the ESC cut the power, but the Rx stayed alive. But I'll definitely look into a separate BEC now.

 

I agree with you over the usefulness of telemetry.

[David Ashby - Moderator]

Just in passing I see that the new Spektrum iphone based app is now available...

 

 

[Ian Jones]

Well I'll just have to wait but the very nice plump chap with a beard and red coat is going to get me a full Hitec telemetry kit (fuel/battery,GPS,rpm,temp sensors). The telemetry can be viewed on the screen of suitabley equipped Hitec Txs however the tx can also be connected to a computer via a cable or an additional HTS Navi receiver (guess what else I'm getting) to display the info which is much easier read and record.

 

All of this information is interesting and potentially useful in relation to the condition of the aircraft but another feature which I haven't looked into yet and is potentially very useful indeed is recording the GPS flight data then playing it back overlaid on Google Earth. An obvious use here would be checking that dead air space is not being invaded but I wonder if it could have any use for pylon racing?

 

So I can't quite answer the thread question properly at the moment but I intend to in due course.

 

There's three displays available, here's the two I can use at the moment, the third GPS one will have to be posted when I have that funcionality:

 

 

[Andrew Clarke 3]

i fly over long grass and have to admit to using the jeti system for model location its a bit like digital water divining

[ntsmith]

I had a DX8 but had a few issues (like losing the RF link which resulted in losing three aircraft) but that was resolved with a replacement. However, I digress. I then had a DX11 as it offered more options - or so I thought by the hype. Not so many that warrants the extra. Now I have gone back to using the DX8 which did everything better and easier than the DX11 and MAINLY because of the telemetry aspect. Its nice to be able to check that receiver voltage and to know if the engine is lean or to have your hands shaken to warn you to land. If anyone ever knocks this radio at least I can say that a radio twice the cost was not anywhere near as good as the telemetry capable DX8. It rocks - and you dont think you need the telemetry. Get used to it. Sell it. YOu will then want another becaus you have become so used to having it. Not used all the time admittedly but it is there!

[stephen bayes]

Posted by Pete B on 28/03/2011 10:57:13:

On the very few occasions I've flown my DX8 telemetry-equipped Tiger Moth and Beaver, I have to confess that I've forgotten to look at the data, after landing, before switching off the Tx............

 

It is impractical to examine the data during flight, certainly anything more than a very quick glance.

 

The flight pack alarm went off on the first flight as I''d set it at a conservative 3.6v/cell, so I've now reduced that to 3.1v/cell, which should give adequate warning. I don't fly to the alarm, just to the timer.

 

I've suggested to Andy Kunz, the Spekky guy on RCG, that a software upgrade to allow flight data to be written to the SD card be considered by Spektrum, in line with the DX10T which has that facility. I'm sure I'm not the only one who has asked the same!

 

Fortunately, I didn't buy the DX8 just for the telemetry - it is a big advance in versatility on my DX6i and I'm already up to a dozen models on the memory. Other makes may be, I'm sure, just as good or even better, but my investment in Spekky Rx's kept me with the brand, and I'm well satisfied with my choice.

 

When they have an altimeter/variometer module available, which must be sometime soon with the 10T now out, I can see real value in realtime data for sailplanes. They will, I think, need a variation in tone for these functions and, perhaps, use the trainer lead socket for an earphone.

 

Pete

Blue tooth lugoil would be good< just the one side

[David Ashby - Moderator]

Chatting to distributors last week, I was told emphatically by one that telemetry is getting a pretty lukewarm reception from flyers in the UK and USA but it's big in Germany.....so there you go

 

 

 

[Richard Wood]

That's interesting David.

Germany does have indigenous radio brands, such as Multiplex

& Graupner supporting telemetry, but these names seem to have

very little UK presence.

The Jeti retro-fit telemetry system seems to be the only reasonably well

established one over here but is a bit 'specialised'.

The other more mainstream brands could start to gain ground soon.

 

Some flyers will never want it - fair enough - & nobody wants to

ogle a screen while flying, but with careful setup of alarms ,buzzers

& whatnot it should become more common.

 

I'll be buying an Aurora next payday

 

[Frank Skilbeck]

It will pick up as more people get hold of telemetry radio's then they will start to use the sensors and appreciate the additional information, as Richard states the Jeti and Multiplex were the first with telemetry systems and they are more widely used in Germany hence you would expect them to take up telemetry first. As regards the US Hitec don't import the Multiplex M-link system so US fliers have had to wait for the Hitec and Spektrum offerings, neither of which had amp or vario sensors available initially, which are probably the most useful IMHO hence the limited take up.

 

I think it's useful though, for instance I was flying a new electric model last week, I knew exactly how many amps I was pulling and also how many mah were left, maybe not essential but quite useful.

[Andy Green]

I like to see my Rx voltage & Li-Po cells pack voltage.

 

In over 30 I've never had a problem, but I do monitor packs throughout the day, or use those LED voltage monitors.

But I do like gadgets and telemetry falls into this category.

 

Andy

[Mike Rieder]

I count myself lucky as I have recently come back into the sport and needed to upgrade to 2.4mz therefore missed the spektrum era! And went for Multiplex due to its telemetry capability. All I can say is fantastic (for my use as i am all electric with some gliders)

The screen is at the top of the set so easy to read and has audio warnings –

for low battery (RX and motor)

temp readings (which I don’t use a lot but can be handy)

Amp usage this gives me a constant read out of the % of juice left in the battery (brilliant)

Vario which is ok but not used to much due to the weather!

Height which is good for electric gliding

Plus more options if you want to buy the relevant sensors.

> >

All of this can be adjusted and warning levels set via a handheld unit (multimate) or laptop.

You also get signal strength info which with the RX battery check this alone is worth the money for peace of mind.

The other plus point is that the Cockpit SX is a lovely set with a great feel and ease of use. The only improvement would be to have and ear piece and a data logger, but I hear these are on the way.

[Bob Cotsford]

there's one thing I'd really like to see - radar for collision avoidance, or to be more precise after last weekend, tree avoidance

[Simon Chambers]

Posted by David Ashby - RCME Admin on 10/02/2012 06:18:24:

Chatting to distributors last week, I was told emphatically by one that telemetry is getting a pretty lukewarm reception from flyers in the UK and USA but it's big in Germany.....so there you go

Does not surprise me. The current 'advanced' Telemetry kit is far too expensive.

Some examples on measuring current consumption:

Hitec - To measure current consumption on the, you need all this: Hitec Telemetry Blue C50 Combo - almost £50, not cheap enough to put on every model. Not only that, you have to fit all those extra wires and sensors over everything.

 

Multiplex - You can buy a inline current sensor that plugs directly into the receiver - Multiplex 35A Current Sensor - a reasonable £30.

 

Spektrum - No current sensors yet available. Mostly Vario sensors.

 

Futaba - From what I've seen, it ;ooks like you will need Futaba's expensive ESC initially. Neat solution to have the current read directly out of the ESC - however I can't imagine it'll be cheap.

 

Jeti - Additional current sensor like Multiplex Jeti Duplex 2.4EX MUI 75 Sensor - 75A sensor for a very reasonable £28. However Jeti have no transmitters yet and requires an existing module based transmitter. Also you have to have a screen tagged on the top of the transmitter, like Futaba's FASSTest system will be.

 

Graupner - I can't see any current sensors. Appear to be mostly Vario sensors.

 

So really there isn't that much out there. What there is, it is quite expensive. Note that none of these solutions are cheaper than buying a Watt-Meter. A Watt-Meter is actually more expensive to produce part wise than any of these additional sensors!

[Frank Skilbeck]

One other point on telemetry is that some Tx suppliers, Multiplex for one, have made their interface protocols available to 3rd party suppliers (e.g. Jet Turbine ECU) so these can be read back through their telemetry system. Also Jeti already have a range of ESCs which interface with their telemetry systems and Multiplex have just launched a range.