Model Boat Mayhem
Technical, Techniques, Hints, and Tips => The "Black Arts!" ( Electrics & Electronics ) => Topic started by: ferny on January 29, 2020, 07:55:26 am
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When I build my Tamar I would like to install some basic telemetry, to measure battery voltage, motor rpm and possibly speed. However I have never done this before and dont know where to start apart from upgrading my tx/rx!
Any help would be much appreciated!
Many thanks
Jon
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Most of the main radio manufacturers make sets with telemetry. These have sensors which connect to the receiver in some way and send the data to the transmitter which can display the data on the screen. Voltage is easy to measure, the sensor has two wires which connect to the battery to read the voltage, you can also get sensors which measure the current to the motor (some of the more advanced radio sets allow you to calculate how much is left in the battery and how much running time you have left.) Speed would normally be measured using a GPS sensor. (some older data loggers did have speed sensors which fitted under the hull but I haven't seen this in modern telemetry.)Which radio set you get will be up to you, do bit of research online to see what sensors they have available. I have experience with two makes,Hitec which uses a separate interface box between the sensors and the receiver, and FrSky where the sensors plug straight into the receiver (if you use more than one they link together.) While FlySky/Turnigy do telemetry I haven't been able to find if they do a GPS so speed is out. There does seem to be difficulty in getting Hitec equipment at the moment so that will probably be ruled out. FrSky equipment is easy to use and connect up although sets like the Taranis have a bigger learning curve as the use of OpenTx firmware makes setting up more complicated although much more flexible.
Jim
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Thanks Jim
Confirmed what I thought and most of all I need to start saving!
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Hi Ferny.
Here are 3 screen shots showing the telemetry that can be sent back to my TX screen from the Rx in the boat.
I could also add GPS, but can't see any need at the moment.
Sorry for the quality, as it's quite difficult to hold a camera and wiggle the sticks at the same time.
It's the new Paladin radio from FlySky.
Mike
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That's pretty neat ! Plenty of information
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I'd be a little concerned about the TX voltage. :o
DM
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I'd be a little concerned about the TX voltage. :o
DM
David
I wouldn't, it's a 3.7v 4500mah battery .
Mike.
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Amazing that for telemetry functionality naval modelers are willing to spend so much money that there is the need to start saving. But it always has been like that. If you d not want to invest in learning then you need to invest money and commercial vendors get rich.
Just lets shortly show one of the infinity possibilities.
An easy way it to use your smartphone or tablet to communicate via WLAN with your model.
(https://images-na.ssl-images-amazon.com/images/I/619CtyZ5RLL._AC_SL1001_.jpg)
This board with an OLD display at amazon (https://www.amazon.com/MELIFE-ESP-WROOM-32-Display-Bluetooth-Development/dp/B07SN3GJ2R/ref=sr_1_15?keywords=esp32+oled&qid=1582215418&sr=8-15) just costs 12,62 USD. At Youtube (https://www.youtube.com/results?search_query=tutorial+esp32+oled) you find tons of tutorials and DIY videos to make available not just the kind of telemetries you find at your commercial suppliers and for which you have to start saving. Just one board connected to a 3.3 VDc battery lets your model interact with your smartphone. Connecting sensors is nearly identical to what you have to do with comercial suppliers telemetry kits. If you go to ebay and search for esp32 you will find boards starting from 0.91 USD. I you search at ebay for esp432 kits (https://www.ebay.com/itm/ESP32-CAM-ESP32-5V-WIFI-Bluetooth-Development-Board-OV2640-Camera-Module-Kit/193107445385?hash=item2cf619c689:m:mm_eLHq50y5Vqv8dxN7J0mw) you find a board with a camera at 6.99 USD + 0.99 USD for shipping.
Just having given you a brief glimpse about the options for the telemetries to those pricey and featureless kits from your commercial supplier. If you buy an Arduino UNO Starter Kit (https://www.ebay.com/itm/UNO-R3-Starter-Kit-Compatible-Microcontroller-ATMEGA328P-270-SYB46-Breadboard/264228398066?hash=item3d853d63f2:m:mY4m9NT8qVy1sn8zGuxDzBw) that you get for 11.09 USD including free shipping you have a luxury setup to make not just the telemetries you can think of but also control stuff from you smartphone! By the way Arduino UNO board can be purchased for just less than 5 USD and its programming environment, called IDE for Integrated Development Environment, Is the software with which you will do all the programming led by DIY Youtube videos..
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Very interesting Hellmut.
But, by the time you order the items that you suggest, given that after you add together the postage costs + the cost of the modules + having the knowledge to put it all together, I think the price wouldn't be that low.
The total cost of all of the telemetry shown on my screen shot was less than €25 and they just plug in and work first time.
Simple is good.
Mike.
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As I wrote. Der telemetry offered by comercial vendors for R/C is ridiculous and by far does not use the possibilities of the 2.4 GHz R/C control systems. It starts with those vendors still speaking about the number of channels der R/C system kakes available. 2.4 GHz systems do not work with channels, a term borne due to the way R/C systems in the MHz frequency band using pulse width modulation, short PWM. The 2,4 GHz systems work with a bidirectional data stream which is able to handle huge amounts of data at the same time from the emitter to the model and the receiver in the model is also an emitter. So huge amount of data could prices requiring to start saving as had been said in this thread. But once you do it you will be able to do things that you do not dream about yet.
Technology vise we are seeing the beginning of the 5G networks and there the use to the device in the internet of things. This will change the world as the 2.4 Ghz technology did for R/C. 2.4 GHz has had the growth in the R/C world because chinese companies were able to make and sell device for peanuts! Same will happen with 5G devices. And there also you have bidirectional transfer rates in the range of many GBytes, but also the chance for a bit lower GigaBit transfer rates for used that are a perfect fit to R/C modelers.
But as I wrote, the traditional suppliers are earning tons of money due to the unwillingness of R/C modelers to learn!
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Hi Hellmut,
Interesting comments/observations. Have you a working esp32 telemetry project?
Regards
C-3PO
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But as I wrote, the traditional suppliers are earning tons of money due to the unwillingness of R/C modelers to learn!
I think you are a little optimistic, Helmut. From my observations many haven't yet learned either how to solder or distinguish the positive pole of a battery from the negative. 8)
DaveM
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Yes, I use the ESP32 and Raspberrys for telemetry. As my main focus right now is getting my workshop in a condition where I can repair my fraise and continue working of the drums for the stepper motor that is my winch on the sailboat. My 3. generation panel uses "telemetry data" from my panel to monitor it and to program it.
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Hi Hellmut,
How do you display the received telemetry?
Have you range tested the esp32 - what's the operating distance?
Regards
C-3PO
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I have not measured the range as I am working exclusively in my workshop.
I do the programming of the ESP32 and the RaspBerry Pi in Python using the PyCharm IDE and so the telemetry data was displayed on the terminal on my PC. Right now, with cooperation of a guy from Argentina we are working on designing a HMI using QT 5. As it is a standardized WLAN device feature the range of Wlan can be expected. But it is possible to add an external antenna to reach higher distances and there are also boards that include LTE so the range would be the planet!
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Hi Hellmut,
I think I am existing is a parallel universe to you - I will PM you.
I just checked out QT 5 - is it really $450 a month or is there a hobbyist subscription? - If not I'll stick to good old fashioned html,css,javascript
Regards
C-3PO
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This is where I have got to using esp32 and an iPad
Will be used on HMS Rodney to control turret rotation, elevation and firing
https://www.youtube.com/watch?v=OR0yWR_9F9c (https://www.youtube.com/watch?v=OR0yWR_9F9c)
(https://modelboatmayhemimages.co.uk/images/2020/02/21/ipad.jpg)
https://www.youtube.com/watch?v=OR0yWR_9F9c (https://www.youtube.com/watch?v=OR0yWR_9F9c)
C-3PO
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If you go to Youtube and search for "tutorial qt5 python" you find a tutorial that also shows how to install Qt 5 for free and how to use it. <no cost, no need to purchase a "commercial license QT".
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@C-3PO: It is great that you show what using an ESP32 or even the older ESP8266 can be achieved. So you are no able to implement and support any number of functions on your model. Great!