Dynamic Controls Power chair, RC Boat trailer project

[gcebiker]

...boat not going anywhere for a while.

Marine shop told me i needed A 'Long Shaft' motor, which didnt fit, so then he told me 'ah well, you will need to order a new transom' ...three months down the track after it took two months for the transom to swim here from New Zealand...and we fitted it up today and now all the other bits dont fit.

...hangs too far out the back.
Steering wont connect

I would of thought that getting in a Marine Dealer would have been a smart thing to do...
I am hoping that he is the nice guy that he seems and will, with any fuss, exchange the motor for a short shaft variant.
After all he was the one that told me i need a Long Shaft when i clearly don't.

Yes i checked before going to the dealer, i thought i needed a short shaft. I had measured the boat per directions and said so to him.

No No No, he says you need a long shaft, ....
Me : U Sure ? i measured it and it needs a short shaft.
He : No you definitely need a long shaft, the Rep from Zego boats was just in here telling me all about them....
Me : oh ok, here is my life savings for a New motor

Just venting, they are closed for the weekend (why a boat dealer that is right next to a popular boat ramp is shut, on a Saturday, is beyond me)
Lets hope he is able to exchange it Monday, I only took it out of its wrapping today.

[Burgerman]

You made the classic error. You presumed the 'expert' knows what hes talking about.

Definition of presumption:
'Mother of all fuckups'...

[gcebiker]

Wired in the 2.4Ghz RC receiver today.
Zip tied it to a plastic 'bolt' container to hold it all in place.

Analog input has been left wired in ...just in case i need it.... maybe i drop the RC unit in the water by mistake , Ill have to put a lanyard on the RC transmitter because dropping it in the drink is a definite possibility.

[Burgerman]

I might suggest a better rx with multiple diversity, esp at low level and around a metal wheelchair. Many things create null spots and multi-path issues on 2.4. I found that from experience of using RC in a house on my chairs for many years. Its very intermittent where there's cars or buildings or lots of WiFi/Bluetooth in the street. Use hopping system like DSMX...

I use an AR10000 spektrum with 3 satellite receivers as a single antenna/rx alone often causes problems around vehicles etc. With at least one mounted high in the fabric backrest. http://cdn.shopify.com/s/files/1/0393/4 ... 1447597453 2 satt's shown. 3 allowed.

I also use a 2 watt WiFi booster to increase 100mW output by 20x plus... I get total reliable safe control at a fair old distance at street level this way. Because a 1 second fail-safe is a long time near water! Or close to expensive cars or roads.

http://www.wheelchairdriver.com/12x.htm

[gcebiker]

Depending on where you live the analogies might not be accurate... i am only driving a very short distance, less than 20meters at the maximum, similar to driving to your letterbox from the garage door and back.

Its in a small park with only a small kayak ramp.

Picture below if from google maps satellite view, if i was better at crawling i would do that instead...


I dont imagine i will be going on my own...ever, lol. This last week with people actually seeing what i have been trying to describe, they have become very positive about it all...most offering their time to 'drive' the boat as i don't have a license as yet...which i will get.

LOSS of signal the trailer will just stop, and corrupt data will also halt the chair.

Driving it with the chairs own power base gives built in protections, if there is a fault in the serial data stream for any reason...it just stops.
And will not start again till the Joystick is power cycled.

ITS MUCH safer than control via the Analog inputs.

With a walking capable helper i am sure if any thing happens ...which will just shut the chair down, they can walk over and drive it close enough so that i can get in and back the trailer myself.

I have been sailing for 12 years since the brain injury accident and i am very aware of having multi back up systems in place.
I have a very keen bunch of fisher friends. Best back up a guy could ask for !

[Burgerman]

Depending on where you live the analogies might not be accurate... i am only driving a very short distance, less than 20meters at the maximum, similar to driving to your letterbox from the garage door and back.

I am flying planes and quad copters miles away over a town full of Wi-Fi and phones with Bluetooth... Thousands of them! Faultlessly, with DSMX channel hopping, 4 separate receivers in different positions and planes, 2000mW RF power.
But I have had powerchairs running on for 1 second before failsafe kicks in and stops them in the house, and around vehicles because of all the metalwork/reflected signals. At 10 paces away. So I do worry! That 1 second doesn't sound like much but it seems like an age when the chair is heading towards a road of your van... Or climbing up a kitchen unit!

[gcebiker]

Marine shop owner says to me today ; 'Ill see what i can do and call you back after lunch today'
...its midnight and still no call, i wonder when he has lunch.

Took the Roller M1 down to the ramp today to check heights and power.
Needs to be raised 245 mm or it hits the ramp (it has a decline, then flat, then another decline)

Chair is GUTLESS, i didnt change any settings (other than to enable the 100% speed , profile 4)
I will need to look into if the power can be improved upon, it wont even back up or turn if i have the trailer hooked up.
Pulls ok tho on the flat, with the trailer and boat hooked up.

No tests as yet with the motor attached till i hear back from the Marine shop.

Worse case , i have to change from linkage steering on the boat to Cable or one of those RC units i have seen on Kicker motors in the USA.

[ex-Gooserider]

Personally I've never liked working with Fritzing - even when using breadboards....

If you want to get into making your own, I'd look seriously at KiCAD - free software, specifically designed for electronics drawing, starting from a schematic and going to complete multi-layer board layout... A lot of the development work on it is done and / or funded by the atom smashing folks over at CERN.... We have several professional board designers at the Asylum, and they tell me that KiCad is comparable in functionality to some of the multi-thousand dollar / seat commercial packages like Altium....

A lot of people like the 'free' version of Eagle, but if you start on it, you will soon find that it has a lot of limitations on board size, layer count, and so on that are designed to get you to buy the 'upgrade' to the commercial version... KiCAD effectively has no limits - or at least not that are more than what you can get made at the typical board house...

Also once done with testing, I'd be wanting to get the hardware into a more robust box, both for strength and for environmental protection...

ex-Gooserider

[gcebiker]

Personally I've never liked working with Fritzing - even when using breadboards....

If you want to get into making your own, I'd look seriously at KiCAD - free software, specifically designed for electronics drawing, starting from a schematic and going to complete multi-layer board layout... A lot of the development work on it is done and / or funded by the atom smashing folks over at CERN.... We have several professional board designers at the Asylum, and they tell me that KiCad is comparable in functionality to some of the multi-thousand dollar / seat commercial packages like Altium....
ex-Gooserider

Thanks, ex-Gooserider. Ill be definitely checking out KiCAD.

Especially now as i am working on the GPS shield for upgrading a regular trolling motor to GPS 'Anchor' Style and in the last few days built up a little Arduino DigiSpark85 as a reef tank fan controller. I would love to be able to offer people the board house plan/link to make their own for this and other arduino shield projects.


Those of you with excellent eye sight may notice i have some wiring issues in that image...they have been fixed and i added the missing Pull Down resistors and a PWM cap for the fan...i had a very bad day .

Mobility scooter not quite working out at the moment...
A, Jim Slade from Slades Marine at Paradise point insisted i needed a long shaft...even after i measured my boat and I thought i needed a short shaft. The steering is not linking up (its fixed linkage steering), tho i am only finding out the problem now...he had known about it for months and had told me to "just buy a new transom" ...
NOW its Christmas and Aussies want to go to sleep on the job as it is...Christmas its 10 times worse.

B, The mobility scooter with LiFePo4 batteries...is NOT heavy enough...an issue when you are towing a 200kg boat and trailer up a boat ramp !
...so lead bricks going back in eventually but for now, parts have been purchased to turn the Mobility scooter/ Boat Trailer into a....Boat Trailer for a CAR

At the moment this will mean a friend parking the car / trailer for me.

...Later on however, I will remove the seat from the Mobility scooter and relocate the tow ball to over the center of the chair...and give it another go

Merry Christmas to all.

[gcebiker]

Dealer eventually took the motor back , that he had ordered in error.

And he only charged me $320 for pay for his mistake...plus the $300+ on the transom i also got following his advice ..after he had seen that it was the wrong motor
4 months ago !

Today i purchased a NEW 6hp 4 stroke Yamaha Outboard with 12v 6amp charging for the Zego and the trailer is being changed into a full Road Register-able Trailer.

I had to up spec the trailer, Main Roads over here did not know how to register a mobility scooter boat trailer and the insurance companies were even more in a spin.
So now its about spec'ing up the M1 Roller with lead acid batteries (LiFe are to light). and seeing what settings i can change to up its power, its a funny thing to drive.

Plenty of go when going in a straight line up quite steep hills but if i try to reverse or turn (on level ground) it gets stuck on its own front castors, Ive not looked into the settings as yet (apart from turning on profile 4). I am sure it will be straight forward to clear up.

I will put the LiFePo4 into the boat, 2 x 50ah LiFe will come in handy with the trolling motor expected to be in use quite a bit.

Just downloaded KiCad, ill post up a decent schematic if i have any success with it.

[LROBBINS]

Consider moving the CG back to take weight off the casters and put it on the drive wheels - perhaps by moving the motors forward. Lightly-loaded casters turn much more easily.

[gcebiker]

The chair has tilt and recline, i have moved myself back as far as i dare and its not helped, pretty sure its a setting that is set to tame.

Chair is in amazing condition, it only cost me $400. I am feeling very fortunate it goes as well as it does with out tinkering much.

[LROBBINS]

Have you tuned the motor compensation? If too low, it will have trouble with "high load" situations, including turn-in-place. Careful though, too high and the chair can become unmanageable, even to the point of runaway behavior.

[ex-Gooserider]

I wouldn't go back to lead brick power - instead keep the lithium pack and add some ballast to get the weight back up - probably the ideal would be lead sheet cut to size, but steel plate would work....

Re the registration issue - if they can't tell you what law requires it to be registered (have a rule to point at that says how) then obviously it doesn't need to be, as it isn't required - though it might require arguing with the cop about this point....

Many years back I tried being a motorcycle courier - I was told that to legally park in the 'commercial vehicles only' spaces, I needed to have signs on the vehicle that met a certain minimum size and content spec (which wouldn't fit) and have 'commercial' plates on the bike instead of the regular 'private vehicle' plates.... I found that the registry didn't have any option for 'commercial plates' on a motorcycle... So I put the biggest signs on the tour box that I could fit, and ran with my normal plates.... Only got one parking ticket, and won the appeal based on the fact that I couldn't be penalized for failing to comply with a requirement that was impossible to meet....

ex-Gooserider

[gcebiker]

...yeah but the lead bricks are easier....AND FREE
I can use the extra range from the LiFePo4 to run the trolling motor in the boat.

I have seen some solar powered small boats and running on electric would save me the trouble of driving on my scooter to pick up fuel all of the time.

...i just wish the brushless trolling motors did not require you to sell a kidney, dam they are expensive.

Boat trailer registration is also necessary if i want to insure it, insurance companies being what they are i dont wish to give them room to wiggle out of anything.

Its more flexible now that i can now tow it with the car or the Joystick wheelchair (when i sort out the settings / balance)



Working on the code for the GPS spot lock trolling motor now..my $100 version of the Minn Kota 'Ulterra'

[gcebiker]

I have the GPS working but the steering is getting me a bit ...pardon the pun, turned about...

I want to prevent wire wrap on the shaft , using the 'standard' gps angle works but does nothing to address wire wrapping...because people , cars, boats dont generally have to worry about that kind of thing i guess.

Is this the cleanest way to do it or am i over complicating things again ?

Code: Select all

 float targetCourse = gps.gprmc_course_to(storedLat, storedLong);
float currentCourse = "input from compass chip"

  if (targetCourse > 180)
  {
    if (currentCourse >  targetCourse) { // current is between 360 & target but target > 180
      turn counterClockWise();
    }
    else if (currentCourse < targetCourse) && (currentCourse < targetCourse - 180) { //current is 0-180 target >180
      turn counterClockWise();
    }
    else if (currentCourse < targetCourse) && (currentCourse > 180) { // current is > 180 but < target
      turn clockWise();
    }
  }

  if (targetCourse < 180) {
    if (currentCourse < targetCourse) { //current 0-target
      turn clockWise();
    }
    else if (currentCourse > targetCourse + 180) { // current > target +180
      turn clockWise();
    }
    else if (currentCourse > targetCourse) { // current > target but less than 180
      turn counterClockWise();
    }

clockWise() and counterClockWise() are separate subroutines (for people new to this stuff, known as 'functions' in Arduino speak)

This is the original code

Code: Select all

steer = gps.gprmc_course_to(storedLat, storedLong) - (heading Degrees)

 if (steer < 0) { steer += 360;}
           if (d > 180) { steer -= 360; }
 if (steer <= -20 &&  steer >= -180)
    {
      digitalWrite(left, LOW);
      digitalWrite(right, HIGH);
    }
    else if (steer >= 20 && steer <= 180)
    {
      digitalWrite(left, HIGH);
      digitalWrite(right, LOW);
    }
    else
    {
      digitalWrite(left, HIGH);
      digitalWrite(right, HIGH);
    }






...which works fine as long as the trolling motor is close to facing the target location.
the "left" and "right" above, are the name holders for the digital pins going to the relay shield.

Ive seen a few examples but they all seem to do the same thing, which is to assume you are facing the way you want to go when engaging auto helm
...but what if you are facing the opposite way ?
Would it be simpler / more robust to just calculate the degrees required to turn Left or Right and take the shorter path ?
which is what the first line of the original code starts off doing, i think..

Code: Select all

steer = gps.gprmc_course_to(storedLat, storedLong) - (heading Degrees)

or do i use a 540degree model ?

...i should be in bed, its past midnight here and i need to go register the trailer tomorrow, maybe in the morning i will wake up with an AhHA idea.

[Jeflemi1]

I had a very similar problem thanks a lot for the helpful tips guys!! I was going to take it into the store but I might just try this project out on my own and save some money

[gcebiker]

Cleared up the syntax errors and turns out i get the same result with either bit of code.

Trolling motor will end up with a single turn about the shaft over time, same as i see on the commercial versions.

[woodygb]

I'm sort of lost as I cannot visualize your steering setup and thus understand the reference to wire wrap around the shaft.

Have you any links to a similar working setup?

EDIT.
Had a look at some GPS Trolling motor pics ...

Question ...Does the motor rotate 360 degrees to get reverse?

[gcebiker]

Question ...Does the motor rotate 360 degrees to get reverse?

Yes, but the trolling motor (diy gps spot lock) is only designed to drive to some GPS mark.

As it approaches the GPS mark the motor will slow down / speed up as it works against the wind and tide.
I think its called a 'controlled drift' if following a contour with the tide but i don't have all that tricky stuff to integrate with a Chart Plotter.

Ive a Yamaha F6CMHS that is currently Tiller steer, fortunately a company in the Netherlands makes a forward control kit for this motor, ill be able to sit naturally and just steer like a car.

[gcebiker]

These Solid PU tyres did not work out, not strong enough for the weight...its a lot lighter than it looks.

Chair was able to tow well with me in it on flat ground, at the very least it will be usefull for putting the boat away if i do end up using the car to tow it.

[gcebiker]

Esky/live well pods made for the back, need to clean off the weld splatter and paint.



9.9HP Long Shaft Tohatsu has been replaced with a 6HP Yamaha, fitting forward controls to it later in the week and the charging kit.

[ex-Gooserider]

Possible solution to the motor wrapping the wire around itself...

For this part, it doesn't matter what direction the boat is headed in, all you care about is the position of the motor with respect to the mounting brackets or some other fixed point on the boat....

Presumably there must be some sort of input to tell the computer which way it is pointed with respect to the mounting brackets, and a way to get a value of 0-360 out of it, or even better plus and minus 360.... Assuming the position number goes positive turning clockwise as looking down on it from above, and that straight ahead is zero, store a value for which direction the motor is turning. (0=clockwise, 1=counter-clockwise) and have some maximum value (say 300*) that is the most you want the motor to be able to wrap the lead around.... Twice the value should be more than 360, and be in a range that you don't typically run with the motor pointed at...

Allow the program to turn the motor as needed in either direction to +/- 300* but if it wants the motor to turn more than the value, require it to spin in the OPPOSITE direction and approach it from the other side...

As each turn command comes in, add or subtract it from the present position to get a new position, and / or read the position sensor to track the current value...

I.e - motor turns back and forth starting clockwise from zero to any position less than 300*, not a problem. Then command comes in that would tell motor to exceed 300* - say go to 320*.... The shortest rotation would be to continue clockwise, but instead require the motor to spin COUNTER-Clockwise to approach it from the opposite side....

Even if working back and forth near the limit value in one direction, there wouldn't really be a problem as the first time over the limit would make the motor spin back the other direction, and then the working would be in a range that wouldn't hit the limit....

Since I'd expect that most of the action would be with the motor pointing either mostly forward or mostly backwards, picking values that would trip when the motor was pointing sideways seems best....

Hope this makes sense....

ex-Gooserider

[gcebiker]

Yeah it has the data feed from the GPS/ NMEA GPRMC sentences and a digital compass.
Apparently i will also need an accelerometer as the swell is going to mess up the compass headings a bit.

This is the code that is working , like you say...most of the time i am going to be pointing right at where i want to go / stay so it should never be an issue or at least not a big issue. I know the DigitalWrite High/Low look back to front...this relay shield works back to front.

Code: Select all

void steering() {

  // calculate relative direction to destination

  int steer = gps.gprmc_course_to(storedLat, storedLong) - (currentCourse) ;

   // check if negative number, turn into positive.
 if (steer < 0) {
          steer += 360;
        }
        if (steer > 180) {
          steer -= 360;
        }



 Serial.print("CTD used for relay control -  ");
  Serial.print(steer);
  Serial.println();
 
  //Turn left
  if (steer <= -20 &&  steer >= -180)
  {
    digitalWrite(left, LOW);
    digitalWrite(right, HIGH);
  }
  else if (steer >= 20 && steer <= 180)
  {
    digitalWrite(left, HIGH);
    digitalWrite(right, LOW);
  }
  else
  {
    digitalWrite(left, HIGH);
    digitalWrite(right, HIGH);
  }
}


The big thing i had completely forgotten was that the motor is up at the moment...the cord with not much extra for getting wrapped around.
...once the Motor is DOWN...i will have heaps of wire and its all springy wire too.

All proceeding well, it should be in the water next week....car launch, its squid season and unfortunately, I don't have the time at the moment to mess about with the Electric wheelchair/launch and retrieve.

...i am a day behind at the moment, shop ran out of Locktite ! for the Remote control plate i put on the F6C Yamaha 4 stroke.

[Burgerman]

You need a 4x scaled up one of these. http://www.wheelchairdriver.com/gopro/test-control.mp4 With current sensors and correctly working motor compensation it drives exactly the same with a 12lb breeze block on top. It just sucks up extra amps. 3mm of stick, it turns.

[gcebiker]

Have you tuned the motor compensation? If too low, it will have trouble with "high load" situations, including turn-in-place. Careful though, too high and the chair can become unmanageable, even to the point of runaway behavior.

It was set to 108ohms...or was the mOhms, i forget. Anyway, i lowered it to 55 and tinkered with the other settings.

Improved the driving a lot...until i attached the boat.
The chair is limited to 55amps and thats where i think the problem lies, the limitation with the motors.

If i get out of the chair and use it for balance, i can slowly get it back up the driveway (which is a slight incline).
It would go faster but walking and driving the chair is difficult.

----
Ended up taking the boat out for its first run on Monday with the help of a friend.
He drove the boat to near where the car was parked and i was able to get from the car to the waters edge, its not something i think would be possible as an ongoing solution.

It had some slight hickups
- The DrawBar bent when the winch jammed and the boat slid off the trailer.
Easy to fix.
- The tow ball did not quite fit.
Already fixed.
...and i had to many people on board, thought it would be ok with 3...and it kind of was but at one point we were all on the one side and it got a bit hairy for a few seconds.

Other than that , very very happy.

Looking for ways (that i can afford) to fix the lack of power in the wheelchair.
I purchased it broken and its all fixed up now so its possible i could sell it back to the store and get a different one, first researching the limits of the motors installed in the donor chair.

They had another one there that looked to have beefier motors and it came with a Dynamic Controller, Ill be calling the store in the morning to see if they still have it.

Ill also bump UP the resistance , trouble is the setting is global...so it will probably make the chair very difficult to drive when the boat is not on the trailer.

More testing is needed !

Tony

[Burgerman]

It makes it easier to drive. The load compensation when set correctly, automatically compensates for load. So the chair will respond the same, either loaded or not, slope or not, grass or tarmac, hill or no hill.

When its not set high enough you must add more power to overcome a load or weight yourself, and then it runs away after you do it. Or it refuses to turn. When set even fractionally too high it over compensates and can run away.

[gcebiker]

It makes it easier to drive. The load compensation when set correctly, automatically compensates for load. So the chair will respond the same, either loaded or not, slope or not, grass or tarmac, hill or no hill.

When its not set high enough you must add more power to overcome a load or weight yourself, and then it runs away after you do it. Or it refuses to turn. When set even fractionally too high it over compensates and can run away.

Ah, i see. Now it makes sense, i will raise the value and see if it helps with the boat...it probably is under powered tho @ only 55amps.

[Burgerman]

You need to increase a little at a time, and test. At the point where it gets too jumpy, you either have turn rate or forward acceleration set too high. Or compensation set too high. In an ideal setup, with a heavily loaded chair, you will get full Amps that the controller can deliver at around 15% turn on the joystick. So turn rate doesn't need to be set high. 40 is a good max value, and 15 for low speed turn.

[gcebiker]

Made the changes to the resistance and its heaps better but still ME + Boat....not working out.

The Chair is to light and its not looking safe (because when i get off the chair lifts off the ground), so for now the wheelchair has become an awesome tool for moving it.
Our street is quite narrow with all the cars parked and its difficult to boat drive out and reverse in.

I park on the street and use the wheelchair to tow the boat down the driveway, along the footpath and then attach to the car.

Here is a video i took today while out squidding. https://www.youtube.com/watch?v=sNlmWI_ ... e=youtu.be