Invacare gb motors

[denis.b]

I am an Italian, I found your forum looking for information about Invacare gb engines. Kindly ask if you can answer my questions.
I bought a unit MKIV-GB, two engines, jojstick, and the programmer.
I adapted this on the old frame of a wheelchair and I have the following problems:
1) Going forward, swerving left and right everything is ok, but going back to the steering is reversed by turning left goes right and vice versa. I tried all the configurations with the programmer but I can not fix the problem.
2) Going downhill braking engines should recharge the batteries (Regenerative Braking) instead current is drawn also to brake. And the unit that does not have it, is resolved by using an electrical circuit or do I need to buy a controller with Regenerative Braking?
3) The following unit: "Brushless Controller Joystick (dual brushless motors for Regenerative Braking end) - IM-50B" http://www.goldenmotor.com/ of GB will be compatible with the motor?
Thank you in advance,
evers

[JoeC]

Welcome, I will try to help

1- I'm not sure if I understand your description of the problem well enough. Does normal turning (forward and to the left, for example) work correctly?

2- Regenerative braking is not perfect, and there are rolling resistances in the chair. Driving down hill might still draw current from the batteries. Stopping quickly should deliver a short reverse current that returns some power to the batteries. I have tried this with two different brushed motor controllers and found it to be true, although I have not tried it with the GB system. I assume that it must do regeneration because most people claim that this system has good battery life (good efficiency), compared to other chairs they have used. I also do not know what the controller would do with the energy it takes from the wheels to stop the chair if it didn't send the energy back to the batteries.

3- No, the Golden Motor controller will not be compatible with your motors. I won't say that it would be impossible to make it work, but it's probably very difficult, and only possible if you have a good deal of electrical knowledge and luck. I wouldn't try it, though, since the Invacare system is much more powerful than 50 amps.

[malamar]

Mi piacerebbe saperti rispondere, Denis, ma purtropppo é poco che sto per rotelle e ancora non ne capisco una mazza..
Ma hai fatto bene a entrare quí: questo é vero covo di scienziati pazzi e sapranno ben loro cosa dirti!

Ciao, Giordano

[LROBBINS]

Ciao denis.b,
avevo lo stesso problema n. 1 quando ho cambiato i motori e l'orientamento del DX-PM sulla carrozzella di mia figlia. Sono riuscito a risolverlo attraverso il programma, ma non mi ricordo ora cosa ho fatto. Ci sono parametri sia per la polarità di ogni motore, sia per scambiare sinistra e destra del sistema. Nei prossimi giorni proverò a leggere i parametri nel sistema di Rachele e forse avrei un idea d'offrirti. Per n. 2, no ho nessun idea. Il PM normale ha la regenerazione (? e detto così in italiano?) e mi sorprenderebbe se quello per i GB non l'avesse. Per n. 3, JoeC ha ragione.

Noi siamo a Siena. C'è qualche possibilità di incontrarci?

Cordiali saluti,
Lenni

[denis.b]

I'm actually using four engines and two units that I mounted on the chassis of adapting an old wheelchair.
With a single command I was able to fly all 4 GB motors.
I use the wheelchair on roads in the mountains very much uphill.
The regenerative braking is essential to recharge the batteries at least in part during descent. The problem is that by connecting an ammeter in series I find consumption in braking
The steering problem is as follows: forward-left-right and everything works out well, back-to-left and back right are reversed (turning the wheelchair back left right turn ... ..).
Yesterday I tried the pram in the mountains and I was amazed with all the force entered the 4 engines, has no limits and torque on each wheel independent suspension is very comfortable.
thank you
Denis

[JoeC]

We would love to see a picture!

[denis.b]

Ok, I just un'attimo I send you the pictures, the arrangement of control units and electrical connections are still provisional and aesthetics for now is very rough.

[woodygb]

4 motors , one joystick and two controllers?

one controller for the front pair and one controller for the rear pair of motors?

[woodygb]

If you have used one controller each side ....I've been trying to mentally visualise what would happen .... then I think it's possible to come up with the scenario's your describing.

[Seajays]

Lets see a picture...Thanks

[denis.b]

I used a logical unit for the front two motors and another for the latter two. it is normal that during the calibration engine speed forward and one backward?
thank you very much
Denis

[Burgerman]

That sentence doesent make sense.

But, either you are unused to driving a tank steer joystick controlled vehicle and "expect" it to steer differently in reverse, or you have one set of motors connected to the controller in reverse. Or correctly but swapped left/right in the software.

How are you connecting two controllers together? I am talking about Input signal here.

[woodygb]

Denis ...

The board needs to know the EXACT setup.

You state that you have one controller for the front pair of motors and one controller for the rear pair.

So one or two joysticks..... and do you attempt to program both controllers at the same time?

The joystick axes programming is a little odd.....it would seem that you can pick almost any config of joystick movement and motor directions

axes.jpg (37.87 KiB) Viewed 15804 times

[LROBBINS]

Woody,

Yes, I doubt if we can be of any help without an accurate description of what modules are connected to what other modules and how the motors are connected to each of these. I have trouble seeing how one Dynamic joystick (and Dynamic puts the major part of the program in the joystick memory) can communicate properly with two PM modules over a CAN bus. Actually, each PM probably has a distinct address, so can read what the joystick says, BUT each PM would have to be addressed by the programmer as well, and I don't know if the Wizard or HHP can do that. Perhaps by connecting the PMs only one at a time and programming each one separately?

I also wonder if the apparent lack of regeneration is because the two pairs of motors are fighting each other, one going "forward" the other "reverse". Given that "reverse" speed is generally set lower than "forward" speed, the chair will move. Note that "forward" and "reverse" are as understood by the controller, and can be reversed with respect to the physical chair. A fight between motors could also explain the steering direction swap - when going physically forward motor-pair 1 is "forward" and stronger and motor-pair 2 is "reverse", motor pair 1 pulls forward and steering is dominated by that pair. Going backwards, pair 2 now thinks it's going "forward", but is actually pulling backwards and steering backwards.

Lastly, where did you get that AXES SELECTION note? I've never seen a description like that in Dynamic manuals, and doesn't match the parameters for the DX system. One can get the same effect with the DX, but in a less direct way, by setting individual motor polarities and swapping left and right.

Ciao,
Lenny

[woodygb]

http://www.invacare.com/HQ/Attachment/2 ... nual_2.pdf

page 30

Perhaps by connecting the PMs only one at a time and programming each one separately?

I'd say that is the ONLY way to program/setup this particular chair.... get one control module and motor pair functioning correctly...disconnect ..then the other pair.
As you say it all depends on what bit is remembering / being programmed for direction swapping...the joystick or the control module.
Easier if it's the control module.

[denis.b]

Cattura.JPG (30.5 KiB) Viewed 15738 times

the defect is already present on the steering control unit using the original standard, and all connections.
Even reversing the axes on the joystick the problem persists.
The parallel command on the two units was accomplished by withdrawing the signal and sending it to both the joystick.
thank you

[woodygb]

Seems fine to me...the coloured cross axis is the control of one motor ( two in your case ) forward - neutral -reverse

Catturaok.JPG (53.66 KiB) Viewed 15740 times

[LROBBINS]

he defect is already present on the steering control unit using the original standard, and all connections.
Even reversing the axes on the joystick the problem persists.

Woody may understand, but I don't.

(1) Is there a separate steering motor that turns the rear wheels left and right? Even if there is a separate steering motor, does the controller also apply differential voltage to the drive wheels to help the steering, or do left and right drive motors get equal voltage even when steering? If the controller does apply differential power to left and right drive wheels, does it do so for both the front and rear pairs, or only the front pair?

Woody's diagram shows the way I imagine you want the chair to turn. What is happening? When you go backwards is it turning opposite of what Woody drew?

For the simplest case, that is if there's a separate steering motor and no differential power to the drive wheels, the steering motor needs to have its polarity reversed when the drive motors are in reverse. If the controller can't be programmed do this, it may be possible to use a diode and DPDT relay to accomplish this. It may, however, be difficult to find a relay, either mechanical or solid state, that could last if it has to reverse full motor current.

For any of the other situations, free-castering rear drive wheels or a steering motor "assisted" by differential power, it will be very important to know exactly what the physical and electrical geometry is before I could even guess at what's going on, and even then I have my doubts about whether I'd have anything useful to suggest.

(2) If the defect was present in whatever the original standard was, why did you expect changing the motors to correct the defect?

The parallel command on the two units was accomplished by withdrawing the signal and sending it to both the joystick.

I also don't understand this. What you wrote reads as though one signal is sent to two joysticks, rather than one signal (from one joystick) being sent to two control modules. Are there two control modules? What are the two control modules doing? Does one control the four wheel motors, and the second control a steering motor? Does one control two wheel motors, and the other control the other two wheel motors? We need a lot more detailed information even to try to help.
Ciao,
Lenny

[woodygb]

Lenny,
Its my opinion that the angled wheels just show the chair turn direction and this is entirely consistent with a normal wheelchair
.....so there is no defect and the original standard was correct..

BUT of course I'm "translating" the sentences and picture then deriving a meaning that may be wrong....

[woodygb]

The parallel command on the two units was accomplished by withdrawing the signal and sending it to both the joystick.
thank you

My translation....

The parallel command on the two control units was accomplished by withdrawing the control signal and sending it to both ( control units ) from the joystick.


Again it's my opinion that Denis is expecting something different from what is normal and thus is trying to fix something that isn't wrong.

The regen charging of this 4 wheel vehicle is a different problem.....

[Burgerman]

These PM boxes and joysticks talk, handshake, comunicate feedback/errors/voltages etc back. Cant see how you can connect two??? Maybe you can with DX as the programming is in the module? Maybe just drive commands sent.

[woodygb]

A rehashed pic with the addition of a mechanical joystick potentiometer setup that may make the motor/joystick relationship clearer,

Catturaok.JPG (75.12 KiB) Viewed 16113 times

[woodygb]

These PM boxes and joysticks talk, handshake, comunicate feedback/errors/voltages etc back

Do they?

Or does the joystick just display errors , voltages provided/communicated by the control unit?

I also suspect the level of electrickery depends on the year of manufacture.

[denis.b]

Ho deciso di scrivere in italiano per evitare incomprensioni utilizzando il traduttore automatico.
Chiedo a "LROBBINS" che ho visto scrive correttamente in Italiano di fare il tramite per chiarire in inglese agli altri partecipanti al forum.
Io abito a Telve Valsugana in provincia di Trento.
Innanzitutto vorrei descrivere nuovamente il problema dello sterzo che si presenta utilizzando una sola centralina MKIV con il suo joystick e un motore a destra e uno a sinistra, tutto collegato senza nessuna modifica e ruote libere di sterzare posteriori.
Con joystick in avanti a sinistra la svolta è sinistra; con joystick indietro a sinistra la svolta rimane a sinistra.
Tutte le carrozzine che ho usato seguono il seguente schema di guida:

Sterzo corr.JPG (25.03 KiB) Viewed 16331 times

Lo schema inviato da “woodygb” corrisponde a come si comporta effettivamente la carrozzina. Questo schema è anomalo perché con joystick in avanti a sinistra la svolta è sinistra ed è corretto, andando indietro si invertono le curvature; con joystick indietro a sinistra la svolta è a destra.

Sterzo incorr.JPG (24.85 KiB) Viewed 16091 times

Non ho ancora capito se si tratta di un problema di programmazione ( lo escluderei perché ho provato praticamente tutte le configurazioni possibili) o se è semplicemente un'altra maniera di guida rovescia rispetto alla nostra.


Per comandare contemporaneamente le due centraline con i 4 motori ho risolto nel seguente modo:
I due motori anteriori sono collegati ad una centralina che viene comandata dal suo joystick lasciando tutti i collegamenti originali standard.
I due motori posteriori sono collegati alla seconda centralina comandata dalla scheda di un altro joystick al quale arrivano i segnali analogici di controllo dal joystick principale; un filo che controlla la velocità(0V avanti, 2,5V fermo, 5V indietro) ed uno per lo sterzo.
In questa maniera le centraline ricevono contemporaneamente i segnali di controllo e possono esser programmate singolarmente.

conness.JPG (28.85 KiB) Viewed 16095 times

[woodygb]

.

Sterzo correct.JPG (28.59 KiB) Viewed 16083 times

[LROBBINS]

Denis.B

Grazie. Questo è molto più chiaro. Nei prossimi giorni proverò a tradurlo, di formulare domande più precise se ce l'ho, ed anche di pensare come avevo risolto un problema simile nel sistema Dynamic della carrozzella di Rachele (i quadri Invacare sono manufatti da Dynamic che è di proprieta di Invacare).

Thanks. This is much clearer. In the next few days I'll try to translate your message to English, ask better defined questions if there are things I still don't understand, and to remember how I resolved a similar problem in Rachele's Dynamic control system. Note, recent Invacare controllers are made by Dynamic (a subsidiary of Invacare).

Woody & Denis.B
Yes all modules talk to each other digitally over a CAN bus (Rachi's chair has 5 modules). For Dynamic, the master computer is in the joystick module not in the PM. Dynamic calls the joystick the "master control remote". Denis.b has neatly bypassed the communication problem by feeding a non-CAN signal generated by one set of modules (that communicates internally by CAN) to a second set of modules (electronic joystick mimic + PM that also communicate among themselve by CAN). A question that come to mind for now is: How does the chair behave if the rear motors are put in free-wheel with the rear-motor controller disconnected? This will tell us whether the problem is in the master control system (the modules for the front motors) or in the slave system (the modules for the rear motors) and/or in comunication between the two controller groups.

Si, tutti i moduli parlano tra loro in modo digitale per CAN (nella carrozzella di Rachi ci sono 5 moduli). In sistemi Dynamic, il computer mastro è nel modulo joystick invece che nel PM. La dicitura usato da Dynamic per il joystick è "remoto di controllo mastro". Denis.b ha superato il problema di comunicazione tra due quadri per mezzo della spedizione di un segnale non-CAN prodotto da un gruppo di moduli (che comunica all'interno per CAN) al secondo gruppo di moduli (l'analogo elettronico ma non meccanico di un joystick e secondo PM che comunicano tra loro per CAN) - bravo!. La domanda che viene in mente per ora è: Cose'è il comportamento della carrozzella se i motori posteriori sono messi in "free-wheel" (non so come tradurre free-wheel in italiano) e il gruppo di controllo posteriore viene sconnesso? La risposta indicherebbe se il problema risiede nel quadro master (i moduli per i motori anteriori) o nel quadro schiave (i moduli per i motori posteriori) e/o nella comunicazione tra loro.

Spero d'aver fatto meglio di un traduttore automatico. I hope I've done better than an automatic translater.

Ciao,
Lenny

[woodygb]

Yes all modules talk to each other digitally over a CAN bus

Lenny the definition of communicate / talk is the big grey area for me.... as I understand it the joystick simply sends packetized information / instructions ( instead of multiple switches and wires ) which the various modules accept/"hear" and if the comms packet is valid /makes sense act on them....if the comms packet isn't valid/ make sense they send out an error message that the joystick software converts to flashing lights.

(0V avanti, 2,5V fermo, 5V indietro)

pots mix volts.JPG (46.54 KiB) Viewed 16077 times

[Ashley G]

Seems fine to me...

<<<< .... snipped .... >>>>

Hmmm. Lookiing at the diagrams, and the angles of the rear wheels particularly, my impression is that the chair does steer incorrectly when the joystick is pulled back.

I would expect my rear-castors to lead off in the opposite directions from those shown with the joystick positions (above).

I can usually follow woody's comments and explanations very easily, and often learn something from them, but on this occasion I am struggling to see how anyone could interpret the diagrams differently from the way I do. I may have missed something but I can't see what that is either

Watching with much interest ....

Regards

Ashley

[woodygb]

This is my interpretation.

The angled wheels are NOT casters they're just a visual/ pictorial indication of the chair direction and are confusing.

I'm visualising this as two wheelchairs bolted together end to end....but without casters.

[woodygb]

Like this of B.M's but with a seat and 4 motors

http://www.fatnfast.com/robot/