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G'day from Western Australia

PostPosted: 09 Jun 2025, 16:34
by Brad_C
G'day, I'm Brad.

About 10 years ago we were given a Shoprider Como power chair in some state of disrepair. As kid No.1 was about 1 at the time, it sat in the corner unloved and taking up space. About the time Kid No.2 turned 1 I was given a pile of ex-UPS SLAs and I thought "Gee wouldn't it be fun to get that chair going". We spent a few weekends doing it up and over the next 4 years it got a pile of use teaching the kids spatial awareness while doing time trials around the back yard. It also had a hitch fabricated for our beach trolley so Kid No.1 could give his friends "rides in the trailer".

When Kid No.2 got cancer, it then got used as a backyard racer, but also as his mobility aid. Back in 2021, Kid No.2 took his final ride on the chair, and it got lent to a neighbour who had his knee driven over in a motorcycle accident. After he handed it back we put it back in the corner. I couldn't really face it.

It has a PG Drives VSI controller and I'd always told the boys that when they were old enough, we'd get some programming software for it and "tickle it up a little".

Fast forward 4 years and Kid No.1 said "Come on dad, we used to have fun on that thing, let's get it going", so I bought a new set of batteries, cleaned up all the connectors, scrubbed the rubbish of the contacts on the drives power buttons and away we went, back doing time trials in the back yard.

I've spent months over the years trawling the new trying to find A) a circuit diagram for the programming cable, and B) the software to unleash the inner beast.
Today I stumbled across this wealth of knowledge, so here I am ready to accept imparted wisdom and perhaps join the discussion from a completely different angle. I've found item (A), and the parts for a cable are in transit.

Re: G'day from Western Australia

PostPosted: 09 Jun 2025, 17:55
by Burgerman
So, sad story. But you want the software?
Be warned that you wont make it faster. But you can make it steer a bit better.

See PM.

Re: G'day from Western Australia

PostPosted: 10 Jun 2025, 00:33
by Brad_C
Yes, sad story.

I appreciate the help. I reckon improving the steering will help our lap times greatly :)
Fun times ahead.

Re: G'day from Western Australia

PostPosted: 10 Jun 2025, 01:29
by Burgerman
Set turn acceleration and minimum turn acceleration to 100.
Set turn deceleration and minimum turn deceleration to 100.

That removes all the delayed action steering input and makes it stop turning when you say so. It removes all the delays and makes it steer in linear fashion like a car or a computer mouse.

If it turns too fast or too slowly, adjust the turn speed and minimum turn speed.

The minimum settings refer to when the joystick is near the centre or when a slow speed is selected.

Set acceleration to 100
Set deceleration to the lowest it will allow.
Set back stick braking to whatever it needs to JUST make the tyres lock up on dry pavement.

Re: G'day from Western Australia

PostPosted: 10 Jun 2025, 09:51
by Brad_C
Very much appreciate the pointers.

I got notification from RS that my FTDI cable is on the way this morning. I have a huge stock of conventional diodes, but my only Schottkys are 5A and won't fit in the plug, so I ordered a small pile of 1A ones also (I'll never run out). Oh look, as I type this my dispatch notification from RS came through. Due next week.

The deceleration through turns has always been a bugbear. So I'm looking forward to having a play with that and perhaps acceleration to try and get off the mark a bit quicker. The chair came without batteries, but was designed for 12AH batteries. I set it up with 17's which should give it a bit more grunt off the line.

Re: G'day from Western Australia

PostPosted: 11 Jun 2025, 08:53
by Brad_C
Nothing like putting a cable together and having it "just work" (tm). The thorough documentation here certainly helps.

Those settings have transformed the chair. No.1 son gives you 2 thumbs up.
We have plenty to play with now as we learn what each setting does.

Re: G'day from Western Australia

PostPosted: 20 Jun 2025, 17:59
by martin007
Welcome!