meyra optimus shopping

[s-car]

Hi everyone,

I'm looking for some advice regarding the purchase of a Meyra Optimus 2 with R-net electronics.

I've been using an Optimus 2 with CAN-bus for about 10 years now and I'm really happy with it.
I'm thinking about buying this new model, mainly because I hope it can reach 15 km/h.
However, I noticed the joystick doesn’t have a monitor, and now I'm unsure if this model actually goes up to 15 km/h.

Does anyone have experience with this version?
Also, is it possible to adjust the CAN-bus settings to make the wheelchair go faster than 10 km/h?

Thanks in advance for your help!
image
https://images.kupujemprodajem.com/phot ... 04e61.webp
https://images.kupujemprodajem.com/phot ... d3895.webp
https://images.kupujemprodajem.com/phot ... 92302.webp

[Burgerman]

Ok where to start..

Many here have R-net programmers. Those only work on R-Net electronics.
The Myra chair you are talking isnt R-net. Well its not ONLY R-net. Its joystick is. Everything else is either modified or made under licence or by third party suppliers.

The programmer will connect. But its really designed for a dual channel tank steered power module. So most of its settings are either redundant or do something other than what you expect. And the part that controls the steering servos is connected to the r-net system and not recognised by it. And for that bit you need myras programmer - at least I think so.

That steers by differential power to the drive wheels. The myra chair uses a power module that LOOKS the same, but is a single channel unit. It drives like a scooter. With a servo controling the steering casters.

Can you increase the speed this way? Well it depends. In a normal powrchair that isnt usually the case. But in the case of myra then they change the max speed in programming rather than in the gearbox (which for technical reasons is a bad way to do things). Except that for you its a good thing!

So the answer it a firm probably! But only as fast as their fastest model that they sell in whatever market that may be. But most of the settings will make little sense. And not behave as you would expect.

So the problem is that you will need a R-Net dongle. Those are becoming harder to get. One sold recently on here. They are not cheap.

The software that you will need is OEM version. And I can find you a copy of that. But first find/buy or steal a dongle.

[Pierro]

Hello s-car,

I have an Optimus 2 in the 15 km/h version and I'm actually very happy with it. I also have an r-net dongle and have already set and adjusted quite a few things. So it's a good idea to save your driving profile first. It's as Burgerman says. Meyra's R-Net is a bit different, and you can't access everything. But there is a Meyra program for dealers. With a few tricks, you can access some settings. Mine goes about 16-17 km/h. But at this speed the tail wags and veers out.

The Optimus with its rear-wheel steering isn't for everyone, but if you already have the previous model, you don't have to get used to it. Off-road, it's unbeatable. I love my black devil. If you have any questions, some people here drive an Optimus 2.

Regards Pierre

[s-car]

Hi everyone,

Thanks a lot for all the helpful replies! So far, I’ve managed to reach around 10–11 km/h using CAN-bus... and with R-Net I’ve seen speeds up to 15–17 km/h. I'm still not sure if those are the actual limits, though.

I really love the Meyra Optimus — it’s an amazing machine — but unfortunately, it’s very hard to get one in my country.

One more question: where can I buy an R-Net dongle?

Burgerman helped me a lot with the CAN-bus part — big thanks to him!

Best regards,

[martin007]

Where are you from?

[Burgerman]

The former yugoslavia, serbia.

[rickystyx]

you can make changes enough to get the 15Km/h, what you can't change or at least I've never been able to find a way to change is the automatic decrease in speed as soon as you put any turn onto the joystick.
This isn't a gamechanger really as the only time I really want to go fast is getting across a road or something similar.
Is fast a good thing? Well it is if you want to get across a road with traffic but it doesn't really come in for anything else but it is nice to have when you want it.
Is being slowed down on turns a good thing - well yes it improves stability but I believe they went over the top with the reduction of speed.
Would I change from my Meyra - not really for off road etc it is great but then you don't need high speed for off road, for comfort it is fantastic but for anywhere where you need tight manoeverability it's pretty awful - it is horses for courses and the Meyra isn't an in house or around the shops chair it is really an outdoor alternative to a mobility scooter with the advantage of being able to fold down enough to get it into an estate car.

[Burgerman]

Yes its a scooter rather than a powerchair. But thats what some need or want. Seems to me though that if you are goung to go with a non tank steer scooter then there are etter ones. The only advantage this hs is that its a scooter that steers by joystick and servos. And drives in reverse!

Why didnt they make it rear drive so that the speed advantage gained not having to tank steer and batter saved can be better used without the stability thing bothering you?

[rickystyx]

it's a good question - a rear wheel drive version would be better but at the moment there's not a choice.
It is better than many of the big scooters when it comes to transportation - none of the biger scooters will fold down enough to go in a car which means you either have to travel everywhere in the scooter or put it into a trailer - that was why I went for the meyra it goes into the car like my other chair and that is a huge advantage.
Transporting powerchairs without a WAV is a pain but I haven't yet found a WAV that can also manage a towbar for moving the caravan - sadly the caravan may have to go as getting the chairs in and out is becoming more difficult as infirmity progresses - fighting with portable ramps is a pain but there's not enough room for a crane with a big chair so there's not a lot of options sadly

[s-car]

Where are you from?

Serbia, Belgrade

[Burgerman]

Where my ExGf cae from. 27 years ago. Shes still here!

[Pierro]

what you can't change or at least I've never been able to find a way to change is the automatic decrease in speed as soon as you put any turn onto the joystick

Yes, that's really a problem! There is a parameter called "Turn speed in %," but according to the original documentation for the Optimus2, it's not functional at 15 km/h. See photo:

Nevertheless, the Optimus2 driving profile contains a number. In my experience, increasing "Turning Speed" makes cornering worse. So the parameter does seem to have some function after all. Also with regard to the other parameters that I have marked in red.

[Burgerman]

Turn speed, minimum turn speed, turn acceleration, turn minimum acceleration, motor compensation, and torque, values all are designed for the main drive wheel differential speed turn control. That affects the while drive algo on the module as it is a DUAL CHANNEL device in a powerchair. In your chair these are electrically and digitaly connected together. As one single channel since its a scooter. They no longer can turn anything. If it tried then it would just be wasting current heating itself up and affecting the drive speed. As they drive a single motor. So non of that can possibly work on your chair.
I have no idea what that could ever do to a seperate system on a differnt module controlling servos that turn the casters.

So whatever it is doing if anything at all is certainly not going to be correct. But I doubt it will do anything. A tank steer algo is very complex. Hundreds if not thousands of lines of code to do that correctly in a well developed system affecting the 2 drive channels.

On a scooter these things (scooter controllers) dont exst. It literally goes forwards and backwards. Thats it.
On YOUR chair, I presume it takes an actuator output, has completely diferent firmware, and software to send a turn signal to a servo controller that is made by myra. And that has its own control algo.

So its all a very weird system. Obviously trying to program that with a normal r-net programmer isnt going to work. It may do a few things. But all of the things it does may be incorrect or have ununtended consequences... I would be very careful doing this. The labels on the various functions may not reflect what it actually does. May be detrimental, may burn or hurt something etc.
Theres over a 1000 parameters you can change in normal r-net. But only 4 or 5 may be doing anything in a single channel scooter version. And maybe doesent do exactly what you think...

A bit like trying to run windows programs on dos or something.

[Pierro]

The Optimus2 - 15 km/h version has a 4-pole motor with two connectors for the power module. The photo shows connectors 2 and 4.

@BM, could that be for forward and reverse? I don't understand.

Actually, it's a completely normal 120A power module. This one is mine:

Could I simply replace it with another used 120A PM if I then copy my driving program onto it?

[Burgerman]

No because it ISNT a standard R-Net part. It is a single channel 220A module running very different firmware designed for myra and their servo controlled steering setup. And you cannot copy your settings to it.
A 120A R-net standard module as uses in a powerchair is completely different thing. Yes they might LOOK the same...

The clue is that yours says 220 on it... All 6 of mine say 120 (120A per channel)
Yours is a single channel unit, with both channels elctrically working as 1 channel. Wiith very basic back/forward scooter power capability.

Same applies to the module they use to do that servo steering. The same casings are used. So they look similar... They are not.

The only one of the 3 modules that might work would be the 6 channel seating module.

[Burgerman]

As I already explained!

Turn speed, minimum turn speed, turn acceleration, turn minimum acceleration, motor compensation, and torque, values all are designed for the main drive wheel differential speed turn control. That affects the while drive algo on the module as it is a DUAL CHANNEL device in a powerchair.

In your myra chair these are electrically and digitaly connected together. As one single motor channel since its a scooter. They no longer can turn anything. If it tried then it would just be wasting current heating itself up and affecting the drive speed. As they drive a single motor. So non of that can possibly work on your chair.
I have no idea what that could ever do to a seperate system on a differnt module controlling servos that turn the casters.

So whatever it is doing if anything at all is certainly not going to be correct. But I doubt it will do anything. A tank steer algo is very complex. Hundreds if not thousands of lines of code to do that correctly in a well developed system affecting the 2 drive channels.

On a scooter these things (scooter controllers) dont exst. It literally goes forwards and backwards. Thats it.
On YOUR chair, I presume it takes an actuator output, has completely diferent firmware, and software to send a turn signal to a servo controller that is made by myra. And that has its own control algo.

So its all a very weird system. Obviously trying to program that with a normal r-net programmer isnt going to work. It may do a few things. But all of the things it does may be incorrect or have ununtended consequences... I would be very careful doing this. The labels on the various functions may not reflect what it actually does. May be detrimental, may burn or hurt something etc.
Theres over a 1000 parameters you can change in normal r-net. But only 4 or 5 may be doing anything in a single channel scooter version. And maybe doesent do exactly what you think...

A bit like trying to run windows programs on dos or something.

[tettralytic]

Hi pierro, I'm afraid you do need a meyra specific p.m. And steering lighting unit. Good news is for you they're available on eBay Germany right now I've just checked. Your unit has 220 in the box. They must join up the bridges in this unit.
Could you point me in the direction of where your connection diagram came from. I have a long-term project of converting my chair from meyra can to r net but so far I've been able to get this information.

[tettralytic]

That should be not able to get this information.

[tettralytic]

Thanks, exactly what I need.

[Burgerman]

Hi pierro, I'm afraid you do need a meyra specific p.m. And steering lighting unit. Good news is for you they're available on eBay Germany right now I've just checked. Your unit has 220 in the box. They must join up the bridges in this unit.

Not sure they do. But the 2 outputs always give the same. So they have to connect to a 4 pole motor. 4 wires. Theres no turn (differential power or diferent copensation possible between outputs.) Only one needs a brake attached and that will give an error on a dual channel one. There may or may not be electrical differences but theres definitely a massive firmware difference.

[rickystyx]

The lighting is done on the seating unit - it has nothing to do with the steering unless I'm missing something
I replaced my seating unit which was faulty with one that keeps the lights working but doesn't alter the seat - I don't need to alter my seat angle I just set it manually and leave it there

[Burgerman]

(I was asked to delete the circuit diagram post by Pierro. Fear of recrimination. What an industry this is...)

Anyway... In this diagram, it shows what I mean. https://www.wheelchairdriver.com/board/ ... &mode=view

The 3RD image at the bottom, is an R-net seating module. On a non myra chair this does the lights.
On all of my chairs. It is an ISM6-L (where the L part stands for lighting).

In the Meyra chair that other module higher up, is doing the lights. The steering and lights module...
https://www.wheelchairdriver.com/board/ ... &mode=view
The clue is in the name.

This is an ISM6-L seating module, that would NORMALLY be doing the lights.
Heres 2, I made earlier... ((c) Blue Peter...)

[Pierro]

(I was asked to delete the circuit diagram post by Pierro. Fear of recrimination. What an industry this is...)

Thank you Burgerman.

Sorry guys, but it's better this way. If you want the circuit diagram, I'll gladly send it to you via PM.

[s-car]

Where my ExGf cae from. 27 years ago. Shes still here!

is serbia?

[tettralytic]

Thanks BM we have made contact.
I took a leaf out of your book awhile ago and brought up Power modules, seating modules, etc including meyra stuff. As you point out it's surprising what you can get inexpensively if you keep looking. Oh my

[Burgerman]

Yes, she was in belgrade, getting bombed by nato. So I imported her to the UK.

[s-car]

Where my ExGf cae from. 27 years ago. Shes still here!

((((((((

[Burgerman]

Why sad?

[s-car]

Why sad?

I regret that she's my ex.

[sergey0]

Also, is it possible to adjust the CAN-bus settings to make the wheelchair go faster than 10 km/h?

On CAN-BUS up to 11.0-11.6 km/h can be done directly from the remote control without programmer. See ServiceManual at this link https://optimusclub.ru/download/0011.pdf
You have to set the Speed Factor parameter to the maximum value of 126.