Electronics price estimation Rnet,Invacare,RoboTeq...

[owenminor]

I currently have this:

And, I'm sure you all can guess, I burnt up the VSI when doing shakedown (heavy stress test...capacitors are on the way...but it's not acceptable reliability).
Keep in mind, I'm shopping on eBay. Not big-dollar, direct from manufacturer. We can't afford that.
I have two projects to complete. Both _depend_ on knowing the real cost of using the speed controller associated costs....Mostly the access to an OEM Rnet programmer or a Invacare GTRAC-PMA90 controller (and any gyro tuning for Gtrac).

So. What does it cost to totally re-program an Rnet or a Invacare?

Invacare is cheap and may be the best price/performance option for project #1, since the bariatric motors on this chair are tough, but old and probably not going to hang at 90A sustained.

However. Project #2 is slightly more adventurous. I've done a _lot_ of work with tracked vehicles like snowmobiles, tracksleds, and swamp tracks. I know sources for just about any size, and there are quite a few unutilized options for chairs.
Although, I'll be machining the track cogs myself to get an even lower gear ratio, I want as high of an amp as possible with the minimal cost. And for that, I'm looking at the Electrocraft 4 pole motors/transmissions (used on some quantums). For that, I think an RNet will be an ok match. motor pairs are ~300 street price, used. But that darn programmer cost question (and I know I'll have to do OEM level reprogramming to move from rear wheel drive mode to tracked mode).

I see a ton of threads for this kind of Q: end in "PM me". Please, PM me with what the real scoop is.
Thank you

[martin007]

Where are you from?

[owenminor]

Where are you from?

I'm in Duluth,MN USA. Just updated my profile.

[Burgerman]

Programming COSTS?

Pogramming the roboteq is free. It looks like this: http://www.wheelchairdriver.com/BM3-con ... Script.txt
And that is years of development and testing. Without this and an awful lot of work and undrstanding and building your own joystick forget it!

R-Net is simple. We have OEM software that works with a easy to get Dealer dongle, with a work around. But you will need to buy the dongle, new, used or whatever. OEM dongles require no workaround and are hard to get. But teres a way at around 450 us dollars. Or about 1/4 that used. 3 sold on here recently. And of all systems available R-Net is the best quality, best built, and most flexible and if you are careful a cheap system too. Read here: viewtopic.php?f=2&t=8857

Pilot plus, old and basic, can be easily programmed with DIY lead and software we have here to MAN or OEM and is reliable. Same software does VR2 etc too. But thats underpowered for any serious use. VSI? It can program that too. But throw it away! With any serious use and anything with bigger wheels or tyres you need at least 100A and preferably more like the 120A R-net.

Older invacare stuff, we have a "fixed" copy of the software that can do all levels beyond OEM. And again a DIY cable so almost free. But thats old now.

The latest is the invacare/dynamic LiNX system. That was one of those run away from systems but recently someone cracked the software and so thats also OEM or better programmable but he charges for it, and you need a dongle, and no garantee it will be updated when new versions are available so it may stop working.

Pride, and permobil, best not go there!

[Burgerman]

Just so you know, that if you change to lower impedance (more powerful) motors, such as bigger 4 pole ones, you will HAVE to adjust the motor load compansation to match motors. Thats not possible without OEM at all on any system.

Also did you see what I paid fror the R-Net stuff? Its was robbery! By me. All basically new. For peanuts. It doesent happen often. But these things do appear here, ebay etc but not for months or even a year at a time. And they get bought up within minutes. So you must be permanantly scanning.

R net programmers too. Many have sold on here at sensible cost. Occasionally. Three sold here 6 weeks back. Also a dealers version dongle can be used. But involves messing around with both dealer and oem software.

You should read the first 3 or 4 pages or so here viewtopic.php?f=2&t=8857

[Burgerman]

Also theres no way any 120A mobility controller can ever work reliably and steer properly with a tank chair tracked vehicle.

Remember that load = Amps. Torque = Amps DIRECTLY and the motor size has no affect on this peak value if at the same max roadspeed/gearing.
And all powerchair 4 pole motors would draw north of 300A if fed 24V. This is limited by the controllers max Amp level. So consider this when you look how many M1 and M2 Motor Amps my powerchair ON CASTERS took turning in place in my hallway.

You really need 120A just to turn a heavy rear drive powerchair on casters. This is a screenshot of my Salsa chair, 6mph gearing, 4 pole motors turning in place in my hallway. Note that its 102A and 114 Amps... If this was "tracked" it would need at least double this figure before it turned. At LEAST!

Real time monitoring via R-Net programmer and laptop. I simply turned in place in my hallway, on heavy carpet in a normal powerchair.

[Burgerman]

And this is an older BM2 chair. Not that here I have a single motor cable hooked through a CLAMP ammeter. The limit is the 100A Pilot Plus power module. Easily reached by turning in place... This is on a normal powerchair. With large casters. http://www.wheelchairdriver.com/images- ... ir-700.jpg


VIDEO. Download first or it wont play properly...

http://www.wheelchairdriver.com/gopro/motoramps.mp4

Tell me - how could any tracked chair work properly without at least 200A to play with And thats not really adequate. The 120A Rnet can only do that for a few secs. Then it rolls back due to heat. Then it rolls back more. And more. Most tracked chairs have serious issues if you are expecting them to turn reliably. And this is why.

[owenminor]

I need an estimate on the going street price to get a dongle that will allow me to get into the OEM settings of an RNet. What am I looking at? Don't care if its a hack or the factory way. Hack is my middle name. If that doesn't work, I'll iterate on higher amp solutions.

You're going to love this, then..... I figured if I could not get an way to reprogram an Rnet120A, I go with the following, over a Roboteq:

SuperDuty controllers (need 2)
https://www.ebay.com/itm/300A-10-50V-24 ... Swa9Fa9ZNn
Mixing
https://www.amazon.com/Quickbuying-DasM ... B0754HVZ3B
Joystick
https://www.robotshop.com/en/gearwurx-2 ... r-180.html

Also theres no way any 120A mobility controller can ever work reliably and steer properly with a tank chair tracked vehicle.

Remember that load = Amps. Torque = Amps DIRECTLY and the motor size has no affect on this peak value if at the same max roadspeed/gearing.
And all powerchair 4 pole motors would draw north of 300A if fed 24V. This is limited by the controllers max Amp level. So consider this when you look how many M1 and M2 Motor Amps my powerchair ON CASTERS took turning in place in my hallway.

You really need 120A just to turn a heavy rear drive powerchair on casters. This is a screenshot of my Salsa chair, 6mph gearing, 4 pole motors turning in place in my hallway. Note that its 102A and 114 Amps... If this was "tracked" it would need at least double this figure before it turned. At LEAST!

Real time monitoring via R-Net programmer and laptop. I simply turned in place in my hallway, on heavy carpet in a normal powerchair.

[owenminor]

With these as the powersource behind a 10s BMS. ....https://batteryhookup.com/products/new- ... 10-20-2020
I'm guessing I can overdrive electrocraft mp36's to that voltage. Worth a try.

[owenminor]

Tell me - how could any tracked chair work properly without at least 200A to play with And thats not really adequate.

Exactly....Size is an issue on existing designs. The tracks are used to stabilize and give contact surface area. However, the surface area is too much, and there isn't a need to have all that track as a just a stabilizer. Think of an optimal design of the track as a partially curved bottom that is no more than 4.5" wide and 18" long. Then run a caster or "wheelie" with either a ski or wheel, depending on terrain (mud/snow would be better with a ski.

The curve gives dynamic contact patch area, depending on the softness of the ground. flat cement will be a small patch. Muddy trail, the full 18".

[Burgerman]

Well it will not turn on a full 18 inches. 6 maybe... You may be surprised quite how bad some of the commercial tank chairs are in regards control. They go forwards and back OK...

[owenminor]

[Burgerman]

Did you ever see a weeble?

[owenminor]

Yes. Same issue as a standard wheeled platform with casters. Just wider casters or skis.

Anywhoo..... About a number on a reasonable price to expect to pay for a dongle for an RNet, and what should I search for?

[owenminor]

Here's another way to get over the initial "it's unstable" perception. Who said the center of mass has to be at the centerline of this track's drive cog?

[Burgerman]

Well if you have patience its likely OEM or dealer ones will be for sale here. Or scan eBay. Anything from £100 up to $450 for new OEM from the US.

The software is easy. Free.

[owenminor]

Is there a reference picture or part #/model# of each respective Rnet dongle? I've tried searching here. And then reading massive threads here. To no avail.
What should I look (out) for?

Thank you.

[Burgerman]

I suppose so. But I dont know it. If you look carefully on the case, one has an A, and one has a B on it. Thats the only difference. And a is dealer. B is OEM.
Usually on here viewforum.php?f=1