Model Zodiac Jet Drive

ersky9xr is the port of the er9x firmware to the 9XRPRO radio.
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stotty1111
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Model Zodiac Jet Drive

Post by stotty1111 » Wed Jun 17, 2020 1:21 pm

Hi all,
I have a model zodiac with an in board jet drive unit, I have the gear switch controlling a diverter gate in the jet drive to achieve reverse.To use the reverse function I need to switch the diverter plate so water is pushed out under the model towards thfront making the zodiac go backwards -- I hope the explanation is clear!!
My question is, can I set the throttle stick so that upwards gives up to full throttle forwards, and moving the stick downwards in the traditional reverse situation, but with the drive system running in the forwards direction but with a setable max speed to avoid the boat getting swamped?
I realise I can just use upwards movement, but I need a reduced rotation same direction as forwards because when junior members of the club use the boat it tends to flood when going backwards!
I have looked a Limits, but that will not work.
Thanks in advance


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MikeB
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Re: Model Zodiac Jet Drive

Post by MikeB » Wed Jun 17, 2020 10:14 pm

A couple of possibilities:
1. Use a (5 point) curve, say 20, 10, 0, 50, 100. This gives 20% (max) "reverse" and 100% forwards. Change the 20 and 10 values to give more or less reverse speed.
2. Use 2 mixes:
+100% Thr Curve(x>0)
-30% Thr Curve(x<0)
Adjust the -30% to give the required reverse speed.

You could also use a logical switch, based on the THR value being less than 0, to switch the diverter gate.

Mike
erskyTx/er9x developer
The difficult we do immediately,
The impossible takes a little longer!

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stotty1111
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Re: Model Zodiac Jet Drive

Post by stotty1111 » Thu Jun 18, 2020 1:18 pm

Hi Mike
Configured the curve option here on the bench, yes that works for me, I'll take it up the pond saturday and give it a whizz!
Just another thought, can the gear switch function be tied in to work with the throttle, ie reverse stick movement to change the gear, or in my case the gate baffle automatically?
Thanks for that Mike!! :-))

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MikeB
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Re: Model Zodiac Jet Drive

Post by MikeB » Thu Jun 18, 2020 2:26 pm

err Yes!
MikeB wrote:
Wed Jun 17, 2020 10:14 pm
You could also use a logical switch, based on the THR value being less than 0, to switch the diverter gate.
L1 Thr<0

Mike
erskyTx/er9x developer
The difficult we do immediately,
The impossible takes a little longer!

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stotty1111
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Re: Model Zodiac Jet Drive

Post by stotty1111 » Thu Jun 18, 2020 4:26 pm

Ok, thanks for the info, however being an absolute dimbo, this is all a bit like black magic, I can do and achieve simple 'stuff' but how would I do

L1 Thr<0

I have had a look at Logical switches , but how to configure 'em'!!
Thanks


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MikeB
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Re: Model Zodiac Jet Drive

Post by MikeB » Thu Jun 18, 2020 7:08 pm

Set the L1 line in L.Switches to:
L1 v<val Thr 0
On recent firmware versions you enter the values by pressing MENU to get to the editing screen where you set:
Function v<val
V1 Thr
val 0
AND ---
Delay 0.0
Older firmware lets you set these on the switches list screen, press MENU on each item to enter "edit mode", then use UP/DOWN to change the value.

When set, switch L1 will be ON, when the throttle is below 0% (centre position), so when in reverse.

Mike
erskyTx/er9x developer
The difficult we do immediately,
The impossible takes a little longer!

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stotty1111
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Re: Model Zodiac Jet Drive

Post by stotty1111 » Sun Jun 21, 2020 7:52 am

Ok, tried the boat yesterday with just the curve applied and a manualswitch, excellent!! Last night I had a fiddle with the switch function , initially without success but eventually the penny dropped and using logic I solved the auto switching, again excellent!!
Many thanks for the assistance Mike, I suppose my problems are age and also that for model boats, nothing 'fancy' is required until something like this project arrives, then I am at a loss!!
Just one more question, when switching the boat on, there is a servo kick of about 90', is there any electronickery can that can reduce this? if not , I will just demount the servo arm and then reinstall when the system has settled down
Software installed - R220


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