Dynamic Controls Power chair, RC Boat trailer project

[woodygb]

Tony is this interface instead of a joystick/pod ...or will it work in conjunction with an existing pod ?.

[gcebiker]

Its a complete replacement but just add a DPDT relay/switch and you could use it inline with the regular remote.

[woodygb]

A question about the deadband.
Why so big.... and doesn't the controller also take care of deadband?

[gcebiker]

A question about the deadband.
Why so big.... and doesn't the controller also take care of deadband?

I see other people using it other than myself from time to time and persons not used to power chairs tend to be a bit heavy handed.

Its got both a large deadband and a constrained max.

This is the controller emulator, the main controller is disconnected from the Power Module.
Well its now an aftermarket controller i guess.

[Burgerman]

A big deadband makes it horrible to drive. 5% is OK. 10% starts to feel a little odd. Total.

[gcebiker]

Ive posted the code so anyone will be able to change the values of anything they wish to.

To modify the code download the free Arduino IDE and tinker away (for people wondering how to edit the code, ie people new to this)

Entry level Robot Wars people will be able to use the donor wheelchairs Power Module, should cut costs a bit when starting up / tinkering.

[gcebiker]

Tony is this interface instead of a joystick/pod ...or will it work in conjunction with an existing pod ?.

The code could also be altered to make this remote work as an Attendant joystick, both could be attached to the Shark Bus at the same time.

[gcebiker]

Video finally finish processing, https://www.youtube.com/watch?v=6x7QHqmzDK8

[woodygb]

It would be simple to add in a few lines of code and have a pin read the 0v-5v output of a 20 turn trim pot, this reading could be used to allow the user to vary the deadband say from 10 to 260.

0v = stipulate 10 as the set coded MINIMUM so 10+0
5v = 10+250

[gcebiker]

M1 Roller wont talk to my Shark Emulator , not such a big surprise but i had my fingers crossed.

Pic of the test rig for the Arduino GPS controller, unfortunately the Brushless trolling motor turned up today and it wont fit, much larger shaft size.

I am still hoping i can make use of it with a pulley or push rod.

I am going to look into getting a mount made on the chair i use daily to tow the boat, as in interim to hopefully getting a Jazzy 623 on government grant funding i had had approved.

Or perhaps the local fella with the dead Jazzy 600 has a change of heart / agrees to a trade.
I am not keen on buying it given its not working for him and has been looked at by the 'Pros' , they said it had a broken motor and if that bears true they are not cheap to replace....

[woodygb]

M1 Roller wont talk to my Shark Emulator

...It would help if you mentioned the control system rather than the chair.... Invacare MK? or Dynamic?.

[gcebiker]

Its a Dynamic REM680A joystick, operates on a CAN bus.
...so off course the RS485 was never going to work...i really should have gotten around to reading the manual much earlier than today...

Ive got Arduino CAN boards already from the UK (ordered when we thought the Dynamic Shark used CAN but it uses RS485)
http://www.hobbytronics.co.uk/leonardo-canbus

Watching videos on CAN communications now, WOW its a whole other kettle of fish.

Looking like i should put the original Qlogic electronics back into the Edge, put the Dynamic Shark Electronics into the M1 Roller (which are in the main house chair at the moment)...doubt i will do that, the Qlogic makes driving around a 'non wheelchair adapted house' a nervous experience.

Ive brand new MK Batteries i am thinking of offering to the Jazzy 600 owner, even if the motors are gone i can still make use of the power module.

[gcebiker]

OMG i had no idea our PC's have calculators that calculate bit conversion/math...ive been doing it (badly) long hand on paper....

[LROBBINS]

Dynamic DX is not only CAN, but a proprietary version at that.

[gcebiker]

Dynamic DX is not only CAN, but a proprietary version at that.

They use a few different protocols, keeps us on our toes i guess. I cant see myself decoding it further, easier to swap out power modules, plenty of Jazzy 600's coming up on the second hand forums, or buy a power module on ebay if i find one for the right price.

[gcebiker]

Pictures for anyone interested.

Insides...looks like a Woody Style plug in would work here, i have one of his Smart phone controllers that went weird when i got a new phone (so it was the phone not the Bluetooth controller)


Where i tapped the CAN bus so i could plug my RS485 Dynamic Shark Emulator in...which did not work as i later found out this joystick uses a CAN.

[woodygb]

Open up that spare interface and replace the two resistors that feed the digipot with solid wire...you will then have a a 2.5v swing about a 2.5v center voltage...0v-2.5v-5v

[gcebiker]

Yeah, its not a JC2000 unfortunately.

i would not like to take it (your controller woody) apart...way to much work went into it.

Ive literally every small Arduino board made recently, i went a bit over board but i find its better to have the bits on hand instead of waiting weeks for them to arrive. Ill just build one up if i need to.

I really like my emulator board being able to plug right into the Bus and off you go. A 3D printed case and factory plugs would really make it look the part.

[woodygb]

If you require a remote ON/OFF you will probably need a small 5v relay to isolate the interface as I believe that the pod uses an ON/OFF that is 24v.
Should you wish to retain the use of the joystick with the interface then a bit of re-coding will be required as it currently reads a 1.2v swing from the joystick and gives the joystick input preference over the bluetooth.

EDIT:-

i would not like to take it (your controller woody) apart...way to much work went into it.

Fair enough. .

[gcebiker]

Maybe i could put the drive electronics from the Q6 Edge in the M1 Roller and stick your BT module in it...mmm

[LROBBINS]

Yes, Woody's hack will work, but with some changes. The joystick in that handset is an inductive unit that has two outputs for each channel. My memory says that they go in the same direction just as shown in Woody's table - > 2.5 one one output is not < 2.5 on the other. The Dynamic software checks that they track each other so you will need two digipot outputs per channel (Woody can advise on how to do that). You will have to check which color wires correspond to +5, 0, steering 1, steering 2, throttle 1 and throttle 2 - Woody's table shows 2 blue wires and 2 yellow, but yours (and the one from my old ACU) have 6 differently-colored wires.

[woodygb]

I don't think fitting my interface would be any problem EXCEPT ....as I mentioned previously for the Dynamic ...the Q-logic ON/OFF switch is I believe @ 24v and will need the addition of a 5v operated isolating relay or similar.

[woodygb]

Yes, Woody's hack will work, but with some changes. The joystick in that handset is an inductive unit that has two outputs for each channel. My memory says that they go in the same direction just as shown in Woody's table - > 2.5 one one output is not < 2.5 on the other. The Dynamic software checks that they track each other so you will need two digipot outputs per channel (Woody can advise on how to do that). You will have to check which color wires correspond to +5, 0, steering 1, steering 2, throttle 1 and throttle 2 - Woody's table shows 2 blue wires and 2 yellow, but yours (and the one from my old ACU) have 6 differently-colored wires.

If that is the case then the Dynamic is very similar to the PG JC2000 ...
You can either use 2 digipots to obtain the 2 + 2 outputs OR simply circumvent the error check after the Arduino by using one digipot and connecting 2 wires to one output.

[LROBBINS]

The problem with connecting two wires to one output is that you defeat the error check when using the joystick rather than Arduino. If one never intends to use the joystick, I guess that's OK.

[woodygb]

You can of course do a similar error check on the channel pairs with the Arduino before outputting one bifurcated signal..

[LROBBINS]

Yes, but as I read what you wrote earlier the two signal wires for each channel will be physically connected, so you lose the check on those when using the joystick. (Or do you feed the joystick into the Arduino?) An alternative to separate digipots would be to feed a single digipot signal to a pair of optical couplers so that there are two isolated physical connections, but I suspect that doing that would end up more complicated and more expensive than adding digipot(s).

[ex-Gooserider]

I assume the guy in question isn't going to get any more work done.... (Never mess with a good wrench, as you will probably need him again..)

I've never done the full circuit board process, but would be willing to give it a shot... There are several folks here at the Asylum that do it professionally, and can check work... If you want to do it yourself, I highly recommend the Free Software program "KiCAD"... Several of the folks here that design boards for a living essentially say that it is as good or better than the commercial programs like Altium (which is several thousand dollars / year / seat) It is a project that was started, and is still partially sponsored by the folks at CERN, I figure if it's good enough for a super-collider... It has a full work-flow from drawing the initial schematic to picking parts, laying out the board and doing all the routing - with output in proper Gerber format that any board house can use... The major board place recommended by folks here is OSH-Park, which is a specialist in doing small runs of boards for the hacker community. Essentially they pool designs until they have enough to fill a full sheet, priced by the square inch of design size for 3 copies... Quality is extremely high, turnaround is reasonable, and cost is relatively low....

ex-Gooserider

About a month ago, I did a bit of work for a guy on two of his chairs , with payment to be an 8 year Jazzy 600....
After the work was done, he changed his mind and said he would keep it, i was disappointed he had changed his mind....the Jazzys not even going, one motor is apparently blown and the batteries are long dead but what can you do right ?

This afternoon i get a text from him asking me how much i would like to PAY for it...with no offer to pay for the work i did on his 2 power chairs...grrr

Anyway, while that texting was going on. I did a short video of the new RC emulator driving about in my driveway.
When it finishes uploading this is the link to it, https://www.youtube.com/watch?v=6x7QHqm ... e=youtu.be

If anyone has any questions could they please post here so that the community may benefit (rather than the PM's please)

If anyone has the experience with making circuit boards could you please get in contact with me.

I would really appreciate someone drawing up the boards ready to go to a board house. I have run out of the stimulant that i have been using for 8 years (it was a banned supplement years ago but i stocked up) and working new information into my tiny head is increasingly difficult.

In return i would gladly purchase the boards and build/test one and post to you for your own use.

Cheers
Tony

[gcebiker]

We just had our electricity bills come in and i don't think they have solar.
Perhaps they were scratching to pay the bill...i am trying to think charitably.

I assume the guy in question isn't going to get any more work done.... (Never mess with a good wrench, as you will probably need him again..)

He's a moaner, forever complaining but not coming to get it fixed, i had to go to his house and only did, so that i could pick up the broken and at the time, unwanted power chair.

Its a lesson learned.

I remember now you suggesting KiCAD not to long ago and i had it downloaded and then completely forgot i even had it.

I think i should start it off and have a good go at it, perhaps post it here for anyone to critique, at the very least if i start it off the bits are there if someone is able to guide me if i get stuck, i bet there are probably loads of YouTube How To videos.

Thank you for the reminder.
Tony

[gcebiker]

Looked at Eagle and KiCad...had no idea where to start, so i tinkered with the fritzing one.

As i don't have the 'edit part' worked out (its half worked out), the parts would work in one view but not in another.
DG419 spec page https://www.maximintegrated.com/en/prod ... DG419.html

So what i have here is a mash up, the PCB view from before.

The Header socket for the Arduino Nano is to long, ignore the bottom pin hole on each header, count from the top to match the pin numbers

The PCB view
Yellow is the top level, orange is the bottom of the board.
The rats next dotted line, ignore that (every time i deleted it, i would loose the trace in another view because i have not edited the DG419 part properly)


And a schematic that makes absolutely no sense so i wont even post it
...but its in the file below if you are super interested in seeing how bad i botched it up.
Ive attached the Fritzing file.

Shark DG419 shield6.zip

Dynamic Shark Arduino Nano emulator board file, work in progress

(22.21 KiB) Downloaded 369 times

Obviously i failed finger painting in pre-school and its all gone down hill from there

[ex-Gooserider]

There are a lot of very good support forums for KiCad. The initial learning curve is fairly steep but the workflow is fairly straightforward...

You start by drawing the schematic, which mostly uses standard schematic symbols, and lines between them. There is an error-checker which will catch some issues, but will not stop mistakes like going between the wrong points, if both points are the right type. It will insist that you label all parts, and connect every pin (or mark it as not-connected) Essentially you have to get the electrical parts and wiring all correct here before you can move on...

Either as you are drawing the schematic, or afterwards, you need to assign each part a 'foot print' which is basically what the part goes PHYSICALLY will look like on the board. This includes the actual pads the part connects to, the physical space the part requires, any silk screen for part outlines and labelling, and so on... This can be a bit tricky given that there are likely to be a LOT of parts to choose from that are all physically different. There is a fairly large library of pre-drawn footprints, but it doesn't cover everything, and one should ALWAYS verify with the datasheet, and preferably with the part in hand that any footprint is actually correct... It is CRITICAL that you save any footprint you use on your local machine and have it as part of the project file. Sometimes they update the library, and if the part in the library changes, and you are linked to it, this can break the board design... If you save the part in the project file, it won't be affected by library changes... If you don't have a footprint for a particular part, there is a tool for drawing them. (also one for schematic symbols)

Once you have footprints for all the parts, you can start the board design program and import the list of footprints, along with the 'rats-nest' of wiring from the schematic. This is where the 'art' part comes in, as you have to drag the footprints around to arrange them in a way that optimizes your ability to route the traces... Once you have the parts where you want them, you take the lines of the rats-nest and turn them into drawings of physical traces until everything is routed... You may need to keep playing with the part layout to make this possible. There are some tools that can help automate the process, but there is still a lot of 'art' to it...

After all this, and error checking to your satisfaction, you tell the layout program to generate the 'Gerber' files that you will actually send off to the board house for production....

This basic workflow is what you will need to do in order to design ANY circuitboard, KiCAD just integrates all the steps into a set of programs that try to make it as efficient as possible.

The thing I don't like about Fritzing is that it is great for making a breadboard layout, but doesn't really give much of a path to go from breadboard to PC board...

ex-Gooserider