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[derekwarner]

Hullo David.....defining belt tension would be a rather abstract unit    of measure, however this belt looks pretty flat..[between pulleys]


I remember a year ago asking about belt tension effect & you confirmed adequate ball bearing support etc


Is there any tension function inbuilt within the motor mount?........and what is the function? of the brass rod athwart the motor mount axis


Again, the hull is superb...[just need to sail her in flotsome, log free seas  ]......looking forward to see her on the water


Derek

[DJW]

Hi Derek


I must admit some eyeballing of the gearbox design...  I've used these belts and pulleys in a couple of other projects, and felt they would be suitable for this use too.


These are the belts
https://www.motionco.co.uk/timing-belts-timing-belts-c-25_38_27.html


In terms of tension, I can adjust the motor position to set a given belt deflection. I'm thinking that at rest I'm starting at 3mm of deflection at the midpoint. Then as the rpm increases the belts own mass will cause it to grip the pulleys. Also I can set the two gearbox units to the same deflection. And in case I'm wrong I'll carry a couple of spares..!


The rpm limit of the belt is 20,000 and I'm only wanting scale ish speed, I've not run the numbers yet but I won't be hitting that. I'll do a calculation and post it.


The brass rod is a tube. I'm not sure whether it'll be needed. It's for water cooling, I'm thinking the whole mount will be a heat sink for the motor and the bearings, if required I can remove some of that heat.


I'll post results, good or bad... 
Best regards
David.

[ChrisF]

Hi David

Well, it looks like we have even less choice of ESC than we thought! It arrived, and rather than the Leopard Hobby ordered it was a HobbyWing Seaking. The spec. seems identical though, apart from no USB, and so I think the Leopard is just a badge engineered HobbyWing. Especially as the program card for the Seaking and Quicrun etc. can be used for Leopard ESCs.

Given the performance Andy has shown for the Quicrun I think I shall be happy with those and the Seaking ESCs.

As per his video all sensorless motors suffer from cogging/hesitation from start up which isn't usually a problem with boats and planes due to prop slippage. However if you want total smoothness and fine control from the off you could always go for a sensored motor and ESC which perform so well in rock crawlers.

Chris

[DJW]

Afternoon All


Progress on a few fronts.  The rudders have been installed and blade shape tweaked, a bit closer to the true Riva shape:








And I've been spending some money...  I really liked the idea of telemetry, so have two FrSky Neuron 40S ESCs...  They are twice the price of the Hobbywing units being discussed, but the telemetry sensors are built in.  Just couldn't help myself...


Anyway, now I have silky smooth control from around 200 to 12,000rpm...  Plus telemetry on the TX indicating port and starboard ESC temperature, Lipo voltage, current draw and rpm...  All sensors built into the ESCs.





I'll put a video together of the motors spinning up and post it soon.


And some thoughts on speed:





Will be interesting to see if the calculations are anywhere near reality.  I think they seem reasonable.  I think slip is reduced on a twin prop installation.


Best regards
David.

[DJW]

Morning All


Thought it might be of interest to post the config screen on the FrSky Neuron 40A ESC, the ESC ships with a USB adapter then uses an app called BL_Heli32 running on a PC (Mac and Linux available too).  The app reads the current config, allows adjustments, and then writes back to the ESC.  The profiles generated can be saved and then in my case pushed to a second ESC, so I have digitally identical ESC behavior.





I'm still very much getting my head around it, but have to say I'm impressed so far.  Amongst other things, accurate setting of the throttle centre point is very helpful to syncronise motors. There's an 'Auto' timing setting, this should reduce the power draw and increase motor efficiency.  The motors are very smooth at the moment, but there's another setting for 'Auto' PWM Frequency, that should optimise frequency for a given throttle opening.  'Sine modulation mode' turns the stepped pulses sent to the motor into a sine waveform, again making the motors smoother.  'Rampup power' is like the soft start option. 'Maximum Acceleration' is interesting, this should allow a more scale performance by limiting the power delivery of the motors.


The manual with a full explanation of parameters is here:


https://github.com/bitdump/BLHeli/blob/master/BLHeli_32%20ARM/BLHeli_32%20manual%20ARM%20Rev32.x.pdf


A downside is that the ESCs are not waterproof, I'll be mounting in a suitable aluminium case that will also act as a heatsink.


And I'm not sure exactly whats doing it, but the motors are running a lot quieter. I suspect it may be a few factors mentioned above, but also the higher PWM frequency that's way out of the audible range...  A lot of ESCs run 8/16Mhz, which we can hear as a whine, or is that garbage... Any thoughts..?


Best regards to all.
David.

[DJW]

Evening All


Been busy getting electrics set up out of the boat, then starting to apply to the boat.  Had to rebuild the masthead light as the LED was intermittent.








So this is the Dash, nav / masthead and dock lights:





I've set the nav / masthead and the dash on one circuit, and the dock lights on another.  Then set up a three way TX switch, Off, dash and nav / masthead, and then third position adds the dock lights.


Also been busy programming up the TX, video to follow.


Best regards to all.
David.

[Stuw]

A great build to follow here. Not only a great looking craft but such detail on the electrical side is interesting! Helping me with ideas for the future...

[jpdenver]

I am continuously amazed at the precision of your build.   It really shows the incredible thought and care you have
taken. 

I hope that one day my my decks will come close to the smoothness and detail yours show. 

Regards, 

Jim Pope
JPDenver

[DJW]

Hi Stuw and Jim


You're both very kind, I think we all spur each other on to keep standards up..!


I've now got all the electronic side of the build together and been able test as a fully integrated system rather than individual parts.


In no particular order:


The boat is getting a heading hold gyro (I had a spare), this is going to be enabled when the skier is enabled to keep the hull heading in right direction.





I've made up some Rx controlled switches, so on/off from a Tx toggle switch.  They have an integrated voltage regulator, so input voltage can be 4.5v to 28v and output can be from 0.8v to 20v, variable for whatever devices are being powered.  So they're pulling power from the balance port of the lipo rather than the Rx. (And can supply more current at a range of voltages. Voltage Regulator is an MP1584en, RC switch is a Pololu 2803.)








A couple of plastic 'stand offs' hot glued in to allow fixing.  3 outputs per switch, so up to three devices can be enabled from same channel, fine for current needs with some expansion built in.





And for some engine sounds...


This is a DIY Arduino based system (not my own design but my version of it) with a dual channel amplifier and one of the voltage regulator boards that uses actual Aquarama V8 startup and running sound samples, running two speaker channels, one speaker built into the bow, and an Audio Exciter that going to be attached under the forward deck, it uses the deck as the speaker surface...  Engine cranking startup sound then a proportional engine speed.  Sound on or off via a switch on the Tx.








And here's the Audio Exciter:





Weighs in at 19g... 3w output.


Three 'boxes' being built in for the electronics.  One aluminium case for the ESCs to act as a heatsink, two plastic cases to port and starboard for the rest.


Next task will be to fit the devices into the cases.


As a side note, I've been really pleased with the Arduino (I'm using the really small Pro Mini), and started to wonder about using one to sense for the presence of water in the bilge and use telemetry to push a warning to the Tx... Anyone tried that..?


And if you've got this far, here's a 10 min video showing the light and sound build so far and the tweaked motor controls too.


https://youtu.be/Rj3ynymx54Y


Been good to get this lot together.
Best regards
David.
 

[ChrisF]

Hi David

That's seriously impressive. Your model is going to be great once it's finished.

You've certainly got those motors running lovely and smoothly now. I take it those ESCs can only be used with that make of Tx?

Chris

[DJW]

Hi Chris


Thanks..! Its taking time but I'm trying..!


I'll try the escs with my futaba and let you know how they perform. I think they should be OK, but no telemetry.


Best regards
David.

[ChrisF]

I thought that would be the case with the telemetry. It's really good to be able to see the RPM, voltage etc.

I'm locked into Hitec now but I see with my Flash 8 with the appropriate Rx and sensors it can display the data. I will look into it one day once I've got my builds on the water.

Chris

[C-3PO]

As a side note, I've been really pleased with the Arduino (I'm using the really small Pro Mini), and started to wonder about using one to sense for the presence of water in the bilge and use telemetry to push a warning to the Tx... Anyone tried that..?

Water Alarm

https://youtu.be/HcpV0flL-zA



https://youtu.be/HcpV0flL-zA

Regards
C-3PO

Code: [Select]

int soundFreq = 700;
int soundStep = 50;

const int ledPin = 13 ;
const int soundPin = 6;
const int sensorPin = A0;

uint16_t sensorValue = 0;

void setup()
{
  pinMode(ledPin, OUTPUT) ;
  pinMode(soundPin, OUTPUT);
  pinMode(sensorPin, INPUT_PULLUP);
  //digitalWrite(A0, INPUT_PULLUP);
}

void loop()
{
  sensorValue = analogRead(sensorPin);
  if (sensorValue > 1000)
  {
    digitalWrite(ledPin, LOW);
    noTone(soundPin);
    delay(50);
  }
  else
  {
    digitalWrite(ledPin, HIGH);
    tone(soundPin, soundFreq) ;
    soundFreq = soundFreq + soundStep;
    if (soundFreq == 1200)
    {
      soundStep = -50;
    }

    if (soundFreq == 700)
    {
      soundStep = 50;
    }

    delay(25);
    digitalWrite(ledPin, LOW);
    delay(25); pause 25ms
  }
}

[DJW]

Hi 3PO


That's interesting, I've not seen that version. I've had a look around and found several Arduino libraries for FrSky telemetry, not had a look in detail yet.


Have you used any of these..?


https://github.com/RealTadango/FrSky


Suggest we move this chat to the Arduino forum thread. I'll put my detection code up there when at my PC.


Best regards
David.

[Mark T]

Very - very impressive     I cannot do electronics but I admire those that can.  Keep the updates coming.

[DJW]

Hey Mark


Well thanks for that, trick now is to get it all running inside the boat without blue smoke...


Forgot to add in the pump, that's now corrected, its on same switch as engine sound but a separate channel. Switch on Tx is a three way so its, Sound Off/Sound On/Sound and Pump On.  Reasoning is that pump will deliver water through exhausts at slow speed for effect, so usually with sound, tickover by the dock and so on. For normal running, water will be fed via the water pickups behind the props and pump can be off.



And I've had to adjust plan a shade with the sound...  I didn't build in a set of wires for the Audio Exciter, so now can't get the wires buried in...  So, its gone midships under the deck.  It has a 3M self adhesive strip thats attaching it to a small flat scrap piece, which is then bonded under the deck.











Overall sound is now improved I think, I can turn down the output from the amplifier so its not maxed out and still get good resonance and sound depth.  I'll put a section on next video that compares the conventional speaker and the Audio Exciter sound wise.


If I'd planned these in from earlier in the build I'd have used several and built them into better positions. They're a fraction of the weight of a conventional speaker, and can generate lower frequencies when attached to a large surface.


Best regards to all.
David.

[Stuw]

Looks and sounds fantastic! Out of my comfort zone but great to see.

[DJW]

Some more Aquarama Bling..!


I was thinking about all the very expensive bits of electronics that I'm about to build in to my boat, and thought it would be useful to know if there was any water on the inside of the hull while its on the lake rather than rely on a blue smoke signal and then suffer the pain that would likely follow...


So I've built an Arduino based bilge water detector and added it to the telemetry that comes back to the Tx. So now I get a sound file played every 3 seconds on the Tx in the event water is detected on the inside of the hull.  I'm thinking two probes near the rudder and propshaft seals.





Full details are here: [size=78%]https://www.modelboatmayhem.co.uk/forum/index.php/topic,66425.0.html[/size]


And a video showing the testing here: [/size][size=78%]https://www.youtube.com/watch?v=9S9OKOHVceM[/size]


Enough of the toys. Back to boat building now...
Regards to all
David.

[Backerther]

Hi
These pics are my way of the water detection and drain which is comparatively simple and currently
adopted in my HMS Fencer 1/96.
But from my experience sailing her many times,I feel it is not so useful as the ship will let me know
by her strange  posture itself if the water should come into the hull to some extent.
At the moment,it's OK to return the ship which is even some 10m away from me....
This is just from my personal experience by the slow -going aircraft carrier model.
1;A famous American-made system
2;The drain pump is powerful enough
3:A red lamp will light on when detecting the water and I set it like this to be seen easily when she comes near.
4/5;Layout
6;Table test with a very small amount of water to refrain from the "flood" around the work bench.
7;No problem on this kind of the water..
8;Very dangerous water in the trial run as if she were hit by the torpedo. After checks later at home, around 2cm or more high water could be seen!!
The bilge pump was not set at this stage. Therefore the pump had better be set in the hull usually for a safe return to the shore.!!


Backerther

[DJW]

Hi Backerther


Thanks for your comments and pictures, nice looking ship build..!



That looks like an efficient system to remove water, and a similar way of detecting water with the sensor.  In my case I really don't want any water at all in the hull so aim is to make me aware as fast as possible if there's a problem so I can get the boat back to the dock. And as always with the Aquarama build, weight is an issue, so while I've worked hard to take weight out of the build, I am aware every time I add a non standard part it is adding weight back again.  The good news is that the Arduino setup adds around 8 grams... So I think the weight penalty is worth the insurance.


Best regards
David.

[DJW]

Hi David

That's seriously impressive. Your model is going to be great once it's finished.

You've certainly got those motors running lovely and smoothly now. I take it those ESCs can only be used with that make of Tx?

Chris

Hi Chris


Just remembered I'd not got back to you on this, so just plugged in the Futaba 6EX with R606FS Rx, and the Neurons are silky smooth right across the range. 


So its possible to use the extended programming capability offered by the Neurons without FrSky RC.  But full FrSky / OpenTX RC needed for telemetry integration I think.


Best regards
David.

[ChrisF]

Hi David

Thanks for that.

Hopefully I shall be alright with the Seaking ESCs which are basically the marine version of the Quicruns which Andy showed running nicely. As well as having some variables, but via a program card rather than PC, I'm pretty sure my Tx has soft start etc. programming options - I need to read the instruction book again!

I do a bit of trickling along but mainly medium to fast speeds and only one motor so I think things will be fine. Good to know there is another option known to work nice and smoothly though if needed.

Chris

[DJW]

Hi Chris


I was impressed with the results Andy got too. If I'd been running my Futaba as originally planned I'd have used same ESCs for sure, can't fault them. As I now have the FrSky system, well I just wanted the telemetry too. To play around with it for this build and maybe understand it future builds too.


I spent some time today getting the electronics into a state ready to fit into the hull. Hope to have some more progress and pics tomorrow.


Best regards
David.

[Taranis]

I don't know if I mentioned it in my build but I usually just fit a continuously running self priming pump. If enough water meets the pick up pipe its straight back out. My SL Shannon is especially prone to water ingress. These are often sold as new or used vending machine pumps and vary from £3 upwards. Mine are usually fed straight off the receiver, I just need to remember to turn it on 




Typically
https://www.ebay.co.uk/itm/Micro-Air-Pump-Water-Pump-Mini-pumps-DC6V-12V-Vacuum-Pump-Self-Priming-Pump/174205314765?_trkparms=aid%3D1110006%26algo%3DHOMESPLICE.SIM%26ao%3D1%26asc%3D20201210111314%26meid%3D4a15b9d094e847389826736ade8cd65d%26pid%3D101195%26rk%3D1%26rkt%3D12%26mehot%3Dco%26sd%3D174502399432%26itm%3D174205314765%26pmt%3D1%26noa%3D0%26pg%3D2047675%26algv%3DSimplAMLv9PairwiseUnbiasedWeb%26brand%3DUnbranded&_trksid=p2047675.c101195.m1851

[DJW]

Hi Andy


They look interesting. I have an old Fireboat that needs a bit of TLC and a new pump. I'll get a couple of those, good that they're self priming.


Best regards
David.