This post is to identify which transmitter controllers are used during each particular manoeuvre and to then work out how to simplify the process with mixers and add-on Modules.
For example, we spend most of our time cruising around the lake and that requires us to control 5 transmitter channels. This project will enable you to mange those channels with just 2 controllers instead of 5.
Controls.
We need a minimum of 5 channels to control the water jets.
We use “controller” here to describe any stick, switch, pot, or slider on the transmitter.
Steering.
Both nozzles are always in unison and on the real boat they work through a steering wheel.
The easiest setup is to put both nozzle servos on a “Y” harness from a single controller.
There is no steering when both motors are stopped, even if the boat is still moving.
Jet Drives.
The jet drives must be capable of operating independently, but while cruising, reversing and at Zero Speed, both jet drives must operate as if one.
At speed, a slight change in either drive’s output introduces “tank steering” and the boat will turn suddenly, no matter what the nozzle steering is doing.
The ESCs ignore transmitter commands to reverse.
Buckets.
The buckets must be capable of operating independently when moving sideways.
What are add-on modules?
A module sits between the radio receiver and the servos, ESCs, etc. and can cause one controller setting to manage more than one function.
They are small, cheap circuit boards and a module may contain a number of boards, or a more complex board.
A module is “fit and forget”, once correctly installed you don’t need to alter anything again.
We bring a module routine into play with a specific controller, each routine has its own.
The Scenarios.
Section 2 of the Hamilton Publication HJ362 Ri A37.pdf gives more detailed guidance of helming techniques, here we are just defining controllers.
Note:- These are Controller defaults when using Add-ons…..
Both buckets work on one controller and are up.
Both Throttles work in unison on one controller (centred)
Steering centred.
Forward Cruising.
Both buckets are up.
Both throttles must work in unison to avoid “tank steering”
Steering as usual.
Ideal control solution - Add-ons default.
The 2 sticks on one gimbal are all the controllers you need.
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Reversing and normal braking during forward cruising.
Close both throttles
Both buckets go down
Both throttles opened slowly until stopped, or slower speed achieved
Steering as Usual
Ideal control solution
Both buckets work on one controller and go down, or to mid-way
Both throttles work on one controller
Steering as usual
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Emergency Stop.
Both buckets down.
Both throttles left open
Centre the steering.
Ideal control solution -
all the above happens when a throttle is moved to the 100% down position.
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Zero Speed and low speed Maneuvering.
Both buckets near the midway position, where thrust is equally shared between ahead and astern. Speed is altered by slightly moving both buckets in unison
Both throttles work in unison to hold boat against tide and are not used for manoeuvring.
Steering as usual.
Ideal control solution
Both buckets work on one controller and are initially at mid-point
Both throttles work on one controller at low speed
Steering as usual
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Moving sideways to Port.
Port bucket is down Starboard bucket is up.
Port throttle slightly faster than starboard Starboard throttle just above idling.
Steering used to keep heading
Ideal control solution
Buckets on separate controllers - Port down and Starboard up
Throttles on separate controllers – Port faster than starboard - Starboard constant
Steering used to keep heading
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Moving sideways to Starboard.
Port bucket is up Starboard bucket is down
Port throttle just above idling starboard Starboard throttle slightly faster than port
Steering used to keep heading
Ideal control solution
Buckets on separate controllers - Port up and Starboard down
Throttles on separate controllers – Port constant Starboard slightly faster than Port
Steering used to keep heading
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Next is to find out how close we can get to these theoretical Ideal control solutions.
To move the development forward, we need our micro-electronics experts and those who enjoy transmitter programming to do their thing now.
The rest of us can continue the discussion and throwing ideas into the ring.