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[Perkasaman2]

Can Mayhemmers share their knowledge and experience of this equipment?
The 'elogger' system reviewed below does appear to be a relatively low cost option which dan be used in model boats. Do any members use this product? Are there simpler or better alternatives available?

http://www.zerorc.com/eagle-tree-systems-elogger-v3-review

[Timo2]

Hi Perkasaman

    Lots of goodies at          http://www.hobbyking.com/hobbyking/store/uh_listCategoriesAndProducts.asp?idCategory=172

    Most bits are for Aircraft and Cars  but can be used in boats


   Timo2

[Perkasaman2]

Many thanks for the link Timo2, unfortunately this outfit don't appear to have a UK outlet and net research indicates that most British buyers order  Hobbyking products from their Hong Kong site.
This company is quite a bit closer and their prices look quite similar.

 http://www.scottishbordermodels.co.uk/             

It seems that model aircraft can be static (tethered) for some performance evaluation and this allows 'data to be studied in 'real time'. Tethering a model boat may not be quite no easy.

[sunworksco]

You may want to take a look at the Hitec 2.4GHz AFHSS RF/TX and RX telemetric combo.
These can be hacked into your radio and with an optional sensor station and PC receiver dongle you can view live sensor data on your PC.
Regards,
Giovanni

Hitec RF/TX module out of plastic case.

[RaaArtyGunner]

Tethering a model boat may not be quite no easy.

Should be OK if the rope/hawser is strong enough   

[Perkasaman2]

Tethering a fast electric could lead to cavitation and monitoring the power performance through the 'transition' to planing could be difficult. Trim alterations would be tough to assess. It's these fast electric issues that telemetry can really help, but I think the hull needs to be 'off the leash' for some of the testing and either record or transmit the data with Giovanni's Hitec setup.

(I would'nt mind some California/Ossie sunshine right now.......... I'm trying to rent a sledge/huskies   )

This hitec equipment looks excellent and I managed to research a UK supplier quite quickly:

 http://www.stevewebb.co.uk/index.php?area=radio&sbplow=0&title=Full+Range+Radio+Equipment

It amazing what these model flyers have available................. I think a 'boat package' for fast electric needs put together/deal price for the underpriviledged  matelots (us).

Giovanni's 'hack' needs put into a planet 5 ............. is this possible/available in the Sunshine State?  

[nemesis]

Hello, RC Model workshop was working on this system about 3 years ago. Do not lnow what happened as he seems to have vanished off the face of the world, it was so he could tell where the shottels were positioned when the boat was in the middle of the lake.  Nemesis

[Perkasaman2]

There'll be a few more of us vanishing, never to be heard of again, if this UK snow does'nt quit some time soon.    ( A mayhemmer and their shottels should always be well connected.....  .

[sunworksco]

Futaba is coming out with a telemetric RF/TX & RX in the next couple of months.
Not much info on that now but you can expect something similar to Hitec since their telemetric system design has been on the forums and easily copied.
Regards,
Giovanni

[HS93 (RIP)]

Jeti have had one out for a few years gps/temp amp pilt tube speed or gps amps volts receiver volts   http://www.jetimodel.com/index.php?page=products&old=0&category=1, I have had one foe some time now great as it's easy to use and small.

Peter

[Max Power]

I have been using the Eagle Tree V3 data logger in a fast electric boat for the past year. It has worked perfectly. I have a few add-ons, brushless rpm sensor, gps expander, LCD read out. I log current, pack voltage , motor rpm, gps speed and mahr used. The 25 inch long mono hull has a surface piercing prop so current cannot be checked by holding the model at the bank. On a 32mm prop and 3S lipo pack the maximum current draw sometimes exceeds 50A. Usefull to know with a 70A esc.

[Perkasaman2]

Many thanks for the info. I recall the Jeti system in use by Peter was the subject of a feature article in MMI magazine some months ago and it was this article which caught my interest. There is a considerable amount of info to review with each of the systems currently available and a cost comparison exercise is underway at the moment.My greatest concern is managing the incoming datadata while piloting the boat and I am fast coming to the conclusion that I'm unlikely to be able to 'multitask' solo at the pondside. Cost aside I anticipate a need for an assistant to  handle the boat on (agreed profile) test runs while I monitor the  incoming data in 'real time', while observing the behaviour of the boat. I suspect a seperate receiver/display may be needed, rather than a data display module mounted on the tx. My assumptions may be wrong but this is my concern.

[HS93 (RIP)]

If you cold get a system that did what the eagle tree did and the Jeti you would have a great system  you could see what was happening and set alarms on the jeti so you did not cook things and then go home and look at the jeti, I could not see myself downloading info on a November morning on to a lap top after a run but at home you could look at more detail. someone has built me a system from scratch using a mini pc board (only 3x3 ) that does a lot of recording but to much for lake side, so you need to go to the lake with a test program and the look at the runs and see what is best and which way you go, but toy need the jeti to stop the sudden pop of speed controller.

maybee next year
by the way have you seen the newer type of speed controler that has some loging built in Castel is one

[HS93 (RIP)]

have a look at

Hacker by jeti

http://www.sussex-model-centre.co.uk/shopexd.asp?id=20522

Peter

[Pointy]

Sorry to drag up a really old thread, but just wondered if anyone had used anything like the elogger (http://www.eagletreesystems.com/micropower/micro.htm). I am specifically interested in monitoring current usage during operation on the water. Motor temp and RPM would we useful too although I am not sure if gluing magnets on the coupling would unbalance it. (Using a brushed motor)


Any thoughts?


Les

[essex2visuvesi]

I think Red181 was using one in his 48" huntsman

[w3bby]

One for sale on Ian's Boats, look under private sales

[Subculture]

You can use an optical sensor too with the eagletree, all you need to add to the copling is a white and black stripe- e.g. paint, tape etc.

[Pointy]

Thanks guys,


I have ordered one with a couple of sensors to play with, I will post my thoughts once I have tested it.


Regards,


Les

[Pointy]

Well great service from Allendale Electronics, the kit arrived yesterday and I have had a chance to play with it.


This really is a great piece of kit. Very easy to set up and install. I have only used it on the bench so far but I am very impressed. With the optional optical sensor and temperature loop along with the included servo y cable I was able to monitor current, volts, motor temperature, motor RPM & throttle position, as well as the total mah consumed. The sensors were easy to mount and configure, I simply used black and white electrical tape around the flexible coupling. It was reading exactly the same as the Turnigy micro tacho I had pointing at the prop. The current/volts readings were pretty much spot on to my bench supply as well. The software supplied is easy to configure and use. It worked without issues on my Win7 64bit laptop.


I can't wait to try the boat in the water, I think it is going to be really interesting to see the differences between the bench tests and real world.


Regards,


Les

[DBS88]

Les please would you provide an update on how this kit worked out now that its been in use for a while, whats good, not so good and what else would you add?

[Pointy]

Les please would you provide an update on how this kit worked out now that its been in use for a while, whats good, not so good and what else would you add?

Wow, you are expecting my brain cell to remember that far back!    Fortunately I did write a blog post about it...

The last job was to sort out the motor and coupling, this proved to be the trickiest part of the rebuild. Electric motors are a real minefield, there are hundreds of motors with similar numbers but totally different specifications. The original setup/motor produced 6800 RPM @ 2.2a on the bench, but I have no idea how it performed in the water as at the time I didn’t have the elogger. I decided to replace the motor for a 550S, mainly because I was having alignment problems with the new coupling. The 550s gave great results on the bench but didn’t seem to translate on the water. This is where the Eagle Tree eLogger came in handy. By connecting the beauty up to the ESC and adding the RPM and temperature sensors, I could see exactly what was going on in the water. It was a real eye opener, on the bench the electronics were drawing only 0.9a, and the prop was spinning at 5600 RPM.) In the water the current maxed out at 10.20a, but averaged about 7a.  (amazing that it didn’t blow the 10a fuse) The speed was slow as the motor reached a mere 2500 RPM max, and after 20 minutes running the motor had reached 90°c (Ouch!). Clearly I needed to either change the motor or the propeller or both.

I decided to try the original motor again, and after making the coupling shorter I managed to get the alignment correct. This was drawing about 1.6a and spinning at 6800 RPM on the bench. Down at the local pond the first session ended after 2 minutes with the boat dead in the water. Fortunately I’d had the sense to run it round the outside close to the edge and managed to retrieve it, without getting wet. A quick look told me the 10a motor fuse had blown. (thats probably the reason why Action have a 15a fuse in their diagram ;-)) After popping in a higher rated fuse I ran it about for 15 minutes, with no issues. Everything worked OK  the speed was much better than the 550s motor, and was probably a bit better at low throttle, I guess due to the fact the 755 has five poles. Once I got back to the workshop I downloaded the data from the elogger and you can see the results in the first chart below. The current maxed out at a whopping 14.5a and the RPM reached about 3000. After 15 minutes the temp was 85°c.  I decided to downsize the prop to a 3 bladed 40mm brass one. Took it back to the pond and ran it around for 15 minutes again. Once again the data was downloaded and the second graph below was produced. Overall much better, current averaging about 8a, although I think I am still going to use a 15a fuse, temps down below 60°c, and RMP up to 4500. The speed was possibly slightly better than with the 50mm prop, although it’s hard to tell without seeing two boats side by side.

Unfortunately the bait boat didn't get a lot of use after the rebuild and has sat in the garage for the last few years, in fact it is currently up for sale on ebay. (it still has the elogger fitted too)


Regards,


Les

[DBS88]

Thank you Les, that’s helpful