Pride Quantum R4000 + R4400 Review (Athena)

[Burgerman]

http://www.wheelchairdriver.com/quantum ... -r4400.htm (Goes to my review page)

Add your own comments if you have experience of this chair here and I will link to this thread from that page.
Add comments even if you dont have direct experience too if you want but please say so!

My summary - bit wide, ugly bum, (hence photo needed below) a little bose heavy, bad programming (like all chairs) and lack of power / range for 8mph version based on physics, others comments on EVERY 8 mph chair and my own 8mph experiments in the past.

Anyone has a photo of the rear quarter of one of these? Or any comments, good or bad, Please add it here!

Thanks. Burgerman

[Swan T.W.]

Burgerman, tried to post pics here, couldn't. Sent them to your email address. The battery door seems to have no purpose,it could be taken off and replaced with a flat sheet of ABS or metal. The box above it holds micro switches and sensors. Maybe they could be moved to the battery door, there"s room. Still waiting for parts, to try and shorten over all length. Anti tip wheels can be moved inward easily and shortened significantly if battery door is replaced with a flush one. This is a trial chair so i'm limited in what i can do. I did try a permobil 350, base was way to long but the build quality was better than the Pride.

[JoeC]

I have just received an R-4000 for my wife to demo. I will post more details as available, so far all that I can say is that it came with a 5 amp charger.

[Burgerman]

Because its cheap... I am currently (!) charging a pair of those MK Gels at 40 amps as I type.

[JoeC]

I just took the R4000 out in the parking lot during my lunch break, and I have the following observations:

First, the good- the arm rests are fairly well thought out, with a decent range of adjustability, fair rigidity, and what looks like reasonable strength. They pop off easily if required for a slide transfer, and have a big brass bushing for the pivot for flipping up. Not bad. The mechanisms of the power seating appear to be reasonably well thought out as well, not relying on overly precise parts or tight tolerances. I can anticipate the mechanisms withstanding some decent abuse without failure. I wasn't able to see in my first look if they use potentiometers or limit switches, or something else. The foot rests have power elevation, and have small rubber bumper wheels on the outer corners. This is of course in recognition of the common use of powerchair foot rests for pushing open doors. It might be a good thing- I know that when we've lived in apartments with hard to open front doors you could always tell which one was ours by the foot rest marks on the door.

Now- the bad. There is no swing-away joystick at all. The joystick cable hangs out precariously, begging to be snagged on something. The power seating cables bunch up and a disturbingly tight radius when the seat is reclined. In my experience this routing is asking for trouble. It's not as bad as the Quickie with Delphi that I saw, but it's definitely putting some stress on the wires. The elevating leg rests use a 1/4 inch phono style plug with a curly cable- just like my headphones- and I worry about their durability and potential for snagging. They're just hanging out there. Also, what I have trouble getting used to is that everything is set up (drive modes, power seating) to be operated with a few buttons and the joystick interacting with an LCD screen.

The chair was able to get up to around 7.7 mph (according to its speedometer) with a long stretch of flat parking lot. It slowed down to about 5 mph while driving up a regulation curb cut with some momentum behind it. I was not impressed with the torque or responsiveness. It came with 73AH MK gels installed, and I don't know what the rating is on the controller.

Programming was (of course) not very good- and of course the vendor dropping it off did not have a programmer.

I'll be driving this home over real sidewalks tonight, so I should have more to report later.

[Burgerman]

If its like the one I tried you will probably hit a tree...

[JoeC]

It's remarkably easy to make a rear wheel drive chair travel in a straight line, especially with the programming options available in the control systems. On the DX system, all you need to do is select an option to add an exponential curve to the steering axis of the joystick, and select the options to reduce turning speed and increase turning acceleration while at full forward speed. Programmed like this you can drive in a straight line over all kinds of bumps, very little effort involved and very fast and precise response to course corrections. You can do extremely well with simpler systems like Pilot+ just by having the turn speed low and turn acceleration high for all driving speeds.

Exactly what these companies have in mind when they program a chair the way some of the ones we're test driving are programmed is a great mystery.

[JoeC]

More observations-

The programming was terrible, I felt seasick from all of the side to side lurching as I dealt with the oversteer. I eventually got a handle on it and made it to the train station. If the battery meter is to be believed, the charge was at 90% at my office, and was dropped to 60% after driving one mile over flat ground.

One disturbing thing I noticed was that after any power seating adjustment (which you must stop the chair to do by entering a mode where you use the joystick for a non-driving function) the chair returns to drive mode 1. I found this out after scraping the foot rest at a curb cut and stopping on the corner to raise them a bit. As I started to leave the corner to cross a busy street I was limited to a top speed of 1mph.

On the topic of speed- the chair is somewhat fast. The speedometer indicated a cruising speed of 7.7 mph, sometimes touching 8.0. Unfortunately, it took very little slope, cross slope, or soft ground to slow the chair quite noticeably. I went across a patch of hard packed dirt and gravel that normally slows the P200 down hardly at all, and the motor sagged down near 5mph. They just didn't have the muscle to keep up the speed. The chair is only geared 0.5 mph faster than the P200, so I don't think the higher top speed is fully accountable here.

After driving the mile over flat ground, the motors felt barely warm. That at least is a good sign- the Quickie S636 motors were far hotter over the same stretch of ground. The saggy speed,quickly dropping battery meter, and lack of overall torque may very well be due to the gel batteries.

The suspension was not terrible. It did little to keep small sidewalk irregularities from rhythmically shaking the chair, but it did take out the worst of some larger sidewalk cracks. I would put it on par with the Invacare Storm series (In the US)- the suspension is better than nothing, but really nothing to get excited about.

I will update the battery percentage when I get home, as well as any feedback from my wife.

[JoeC]

On the way home from the train station we had to make a side trip of 1.5 miles, and the battery gauge went all the way down to 37%. We had a lot farther to go so we called a friend nearby and left the chair there to charge while I continued with her on foot. By the time we came back, visited for a while, and made our way out, the chair had been sitting on the 5 amp charger for about 2.5 hours. The battery indicator said 100% (as you'd expect due to the surface charge) and it went down to about 72% by the time we got home, just over a mile away. Overall, I would not trust this chair for much over five miles of real world driving with just curbs and ramps, no real hills. I really can't figure out how it is so bad- my wife put well over ten miles on her chair today, and she has 2+ year old gel batteries. The speed difference is very nearly 7 mph for the Invacare Storm Ranger X, and just under 8 mph for the Quantum R4000.

Other things I noticed- the power tilt system does not seem to use a center of gravity shift, which seems to be a large part of why the seat is so far over the wheels. With the seat completely flat and the foot rests completely down, I measured just over 50 inches from the tip of the toes to the end of the anti-tips. I was obviously unable to turn around inside of elevators which I am accustomed to turning around in.

I also found a lot of situations on the drive home that required using momentum and luck to get over sidewalk obstacles that shouldn't have been a big deal. I was skidding the wheels a lot (not on purpose) during course corrections and getting stuck in curb cuts, high-wheeling between the casters and the anti tips, having to rock the chair with my body or stick my legs out to push off the ground to get the drive wheels to touch the ground. My wife hasn't driven it yet, but she's not excited to do so. She said that the chair looked like it was going to tip over, and she didn't like the way it looked like it was lunging all over the place.

It looks like she'll get another Invacare.

[Burgerman]

Faster chairs like that one (8mph?) from pride are always gutless and lack torque and eat batteries. Its a combination of gearing, dismal programming, and gel batteries. And battery crunching nose heavy attitude. I found the same thing when testing even the 6 mph one and it is supposed to have 20 percent better torque...

Thats why I was surprised how much better the 8.5mph groove felt. And why I used its motors.

8 Mph needs bigger (lower resistance) motors and AGM batteries and solid programming to be any good. Hence my 36v 150 amp+ setup.

Seems you found the same thing as I did. The 6 mph one might be ok for her if it was 10 inches shorter. And lighter! It surprises me how the biggest powerchair company can make something so long/gutless and hard to control.

[JoeC]

The R4000 completely failed to impress in any way. It's only 8 mph compared to 7 that she's use to for every day, or nearly 7.5 mph on the Quickie P200. That chair will easily do 3x the range, and is far easier to drive.

Even the Invacare Ranger X does a tad over 7 mph, and as a more fair comparison has all of the power seating, unfavorable seat position, and two year old gel batteries, and it demonstrated its ability to do 10+ miles yesterday. Does my extra 100 pounds of body mass make all that much difference?

I am not sure I really understand what's happening here. Running the batteries down that fast without doing a lot of mechanical work should make something on the chair very hot- mostly the motors. The energy has to go somewhere, right? Well, the motors really didn't seem very warm. Maybe the chair was supplied with bad batteries, or maybe the battery meter was really unrealistic. I guess if I'd purchased that Hyperion charger already I could have done a little more investigation on that!

[Burgerman]

>>>Does my extra 100 pounds of body mass make all that much difference?

With the extra gearing, your extra weight as well as the forward c of g on a heavy chair - yes its exactly what I have been trying to tell everyone all along. It adds up to a huge difference.

8mph is too much speed for heavy people, (only balarinas need apply). Along with the gel MK batteries (which are just about ok in a 6mph chair with skinny driver) its way too much.

The only way to go 8mph with your weight is to have the most efficient everything (c of g, lighter chair, thicker cables, AGM Odyssey batteries, good programming, air filled tyres etc. Then its almost feasable. But range still suffers.

My new chair will have half the range of the 6mph MK2 one. Reason? Same amount of watt hours, twice the speed... And the gearboxes on the groove motors are less efficient (two sets of gears, including worm, then reduction compared to one large diameter worm). But it fast charges and is for fun so I dont care. http://www.wheelchairdriver.com/BM%20MK ... lchair.pdf For fun, provisional!

I should sell these things. Your wife would buy one... Remember that the MK2 one with 36v will do 6.2mph plus 50 percent. So 9.3mph with mountains of power and control if roboteq powered. Or the New MK 3 one will do 8.5 mph with a pair (24v) of odyssey batteries. You dont have to go to 12.75 mph. The same batteries fit, 3x 1200 or 2x 1500.

BM is for Burger Man obviously!

[JoeC]

That's really lousy to cut the range in half with a user that weighs twice as much! Adding her to the chair adds 35% to the system weight, and adding me to the chair adds 88% to the system weight- the system doesn't seem very well done if there's a huge drop beyond the proportion of increased weight!

It's a good thing she's so light- she really likes sitting over the front wheels and can't go without her power seating. I doubt your Roboteq chair could do much to improve that situation... I plan to build her one from scratch after the ultralight conversion, if we have some stability in our lives at that point. It would use a higher efficiency motor and a single stage belt or chain reduction that would allow for a real and functional rear suspension, and it would have froglegs casters in front.

[Lord Chatterley]

As I started to leave the corner to cross a busy street I was limited to a top speed of 1mph.

Unbelievable, absolutely unbelievable...

[JoeC]

It does it every single time you adjust the seat, so you can plan for it and understand that it's going to happen- but it's still inconvenient.

[Lord Chatterley]

Or the New MK 3 one will do 8.5 mph with a pair (24v) of odyssey batteries. You dont have to go to 12.75 mph. The same batteries fit, 3x 1200 or 2x 1500.

Your new battery tray will be able to accept a bigger pair of Odysseys at 24v for 8.5 mph too! [not sure if your MK 2 would.]

[Burgerman]

Both NK2 and MK3 chairs can take (and will take) either 2 group 24 batteries, or two Odyssey PC1500 batteries, OR 3 Odyssey PC1200 and run 36v -- Controller allowing. But I may retrofit all my chairs with the Roboteq as its much more powerful - at least with Odyssey rather than Gel batteries.

[JoeC]

I would probably still use the DX2 for a chair I build from scratch. The fail-safe design has been beaten to death and passed ridiculous levels of scrutiny. I know how to program it to have a very favorable character. It's capable of tweaking the battery gauge to function passably with a lithium chemistry that doesn't require a charge voltage higher than the lockout level- and I believe the Valence batteries are such a chemistry. Power seating and auxiliary devices can plug into the system seamlessly, and can take whatever switches I like. For my wife's needs, I think DX2 is great for everyday use- only for sports would Roboteq be a stronger contender. Before I get into these projects we will have to see what 2012 brings.

[Lord Chatterley]

I would probably still use the DX2 for a chair I build from scratch. The fail-safe design has been beaten to death and passed ridiculous levels of scrutiny. I know how to program it to have a very favorable character. It's capable of tweaking the battery gauge to function passably with a lithium chemistry that doesn't require a charge voltage higher than the lockout level- and I believe the Valence batteries are such a chemistry. Power seating and auxiliary devices can plug into the system seamlessly, and can take whatever switches I like. For my wife's needs, I think DX2 is great for everyday use- only for sports would Roboteq be a stronger contender. Before I get into these projects we will have to see what 2012 brings.

Reading between the lines Joe, did you get the impression that they maybe thinking of a DX with more volts/amps?

[Burgerman]

Agreed. Unless you consider the 50v advantage. That makes it twice as powerful at the same Amps. And its more. It only matters though if you are looking for getting speed out of the system as well as torque. But your wife is light. But you miss out on the challenge of figuring it all out!

[Lord Chatterley]

Both NK2 and MK3 chairs can take (and will take) either 2 group 24 batteries, or two Odyssey PC1500 batteries, OR 3 Odyssey PC1200 and run 36v -- Controller allowing. But I may retrofit all my chairs with the Roboteq as its much more powerful - at least with Odyssey rather than Gel batteries.

I meant a pair of 2150 Odysseys.

[Burgerman]

Reading between the lines Joe, did you get the impression that they maybe thinking of a DX with more volts/amps?

I think more amps is not likely. Allowing 36 or 48v is a better option as otherwise there is a problem... Cables and connections, physical sixe of motors etc as well as losses in the controller all double with twice the current. More waste as heat etc. Increasing the voltage side steps that and increases efficiency with no real cost increase.

Thats why models use lots of volts. Ibot used 72v etc.

[Burgerman]

>> I meant a pair of 2150 Odysseys.

Ah, well that was a possibility, but I went with 36v and three 42Ah batteries instead! I prefer speed. The roboteq allows that and this increases efficiency a little too.

[Lord Chatterley]

>> I meant a pair of 2150 Odysseys.

Ah, well that was a possibility, but I went with 36v and three 42Ah batteries instead! I prefer speed. The roboteq allows that and this increases efficiency a little too.

But will it be an option with your new battery tray?

[JoeC]

Reading between the lines Joe, did you get the impression that they maybe thinking of a DX with more volts/amps?

From my discussions with Dynamic engineers, no- I do not see any controllers with higher current limits or substantially higher voltages coming from them any time in the foreseeable future. They are aware of the promise of new battery technologies and they do tell me that it's on their radar. That's all the firm information that I have. They're aware of lithium, and they're aware that their present system doesn't interface with a proper BMS that would be needed to make the best use of the batteries.

They are presently working on DX3, but if you look at the length of time between DX and DX2, I wouldn't expect to see it announced for at least two or three years at the soonest. Because it's in development they won't talk about it, but you can bet that they'll do whatever their leaders thing will make them the most money. That's what you can expect from a business. If they think that interfacing with lithium will give them an advantage and make more sales, they'll probably do it. If they don't calculate a good payback for their investment, they probably won't.

I'm not holding my breath. My wife really doesn't have any extraordinary needs from her daily chair- it just doesn't seem that anyone's done anything better than the ten year old design that she uses now.

[JoeC]

Agreed. Unless you consider the 50v advantage. That makes it twice as powerful at the same Amps. And its more. It only matters though if you are looking for getting speed out of the system as well as torque. But your wife is light. But you miss out on the challenge of figuring it all out!

But I don't want to figure anything out for her daily chair! She doesn't care if it has the same range, speed, and comfort of her present chair. She would like a tiny bit more speed and more comfort in terms of suspension, but she'd do without those without much complaint. What she wants and what I want is a chair that is dead reliable, durable, long lasting, and almost never fails. She has to go through bad neighborhoods, walk home alone in the cold, and gets caught in the rain. Having to make a call for help on any kind of a regular basis is unacceptable. Anything to make her wonder if the chair is going to stop functioning while she's out is unacceptable. Unpredictable part failure causing multiple day long waits for repair is unacceptable.

When I design a chair, all of the unique parts (frame, etc) will be massively overbuilt and tested beyond her potential to abuse them. All parts that can wear out will be made in a way that the wear is obvious and a slow graceful degradation, and these parts will be selected for long term off-the-shelf availability. The whole chair will be built in duplicate (with some parts in triplicate for destructive testing), and spare parts will be kept in a closet.

It will be a lower performance chair than Burgermans in many ways, but the neurotic attention to reliability, fault tolerance, and ease of repair will comfort her like a warm fluffy blanket.