Woohooo!!!!! I am a real boy & can start my own topics....

[AdamB]

For starters, thank you for fixing the issues preventing me from posting... I am excited to get started but I have some questions 1st...

Sorry about the length!!! I'll try to keep it as short as possible... I am just waiting on some answers so I can place my order with Gary... In terms of the actual order... I live in Oakville too & was hoping I might be able to pick up my order directly from the shop/him or maybe somewhere in the community? I can work around your schedule/availability... Whatever works, it just seems silly to ship something from Oakville to Oakville

Anyways I organized my post by the specific products in question... So it should be easier to understand... Thanks again for all the support...

Alright everyone...

I finally have the financial resources to proceed with a version of my proof of concept chair & I wanted to run a few things by everyone...

To start with I am planning to use

2# Magic Pie 5 motors- GM.ca (thanks for the Android finally, someone actually listened, sweet!!!)...
2# Nobby MTB Tires-

-I am thinking about using 2# 26" rear type because the rear is centered (as far as I know)... Explicitly, I am not using 1 front/ 1 rear... I am using one or the other & they will be side by side, not 1 in front of the other! So I need to choose either 2 front models or 2 rear models... Not a good idea to use 2 different motors side by side...

I am certain on the 26" as they will have a high camber angle & will fit perfectly under the seat at that height! I also need to confirm that forward/reverse is available at all times on the MP5, it can't require rewiring to use 1 or the other, I need 1 or the other at any given point (I.e. Press button, reverse joystick, etc. Get reverse) depending on circumstances.

To be clear, I will be individually controlling each motor/side with separate controls (thumb throttle is a joystick type controls, right? If so, then I can covert it to any type of joystick... Only thing the wheelchair companies did right...).

Eventually, I want to have the wheels remade with motorcycle type tires/hubs but until then, I'll be content with mountain bike tires... However I don't know what size tires I need/can use on the MP5 hub & I don't know what type of tire/wheel it uses... Cincher, tubeless, etc...

2# Sets of DocBass torque arms
2# Independent Suspension Springs (1 per wheel)
With Either
1#.Custom Frame
Or
2# Cut Up Bike Frames (Rear or Front)

-So 1 arm per each side of each wheel for a total of 4 torque arms per device... I am actually going back & forth between using 2 cut up bike frames or making my own frame from scratch in which case I don't know if I even need the torque arms at all... I like docbass's torque arm design best as there's no moving parts, strongest I know, simplicity (KISS), ease of installation, etc... (no this is not advertising, nor am I associated in any way, I just like them)... Either way $50 seems like a small price to pay for such insurance...

Each motor/wheel combo will have its own independent Spring Suspension to keep wheels in contact with road surface.

2# 203mm Disk Brake Rotors- GM.ca
2# 203mm Rear Hydraulic Brake Set- GM.ca
2# Brake Actuators- GM.ca

-I am planning on using the 203mm size but I can not find any confirmation what size rotor fits on the Magic Pie 5... I have no doubt I could make use of the larger rotor since there's a lot of weight, speed & additional risks specific to the target population... So the extra breaking capacity is worth it even with the incoming weight penalty but I don't know the MP5 can use such sizes...

I am planning on using a hydraulic system & at 1st blush, the options listed on GM's site & here are what I was thinking... Am I missing any components to make the system work? Are there other hydraulic disk brake options that I would be wise to consider? If I can't use the 203mm, what's the largest size I can use?

Finally, what sort of adaptor do I need to incorporate such a system & where do I find it...

4# Group 24 70A SLA Gel batteries in variable 24V/48V configuration- Already Own
1# 3 (or 4) Position Keyed High Voltage (min 60V) Switch- GM?
1# Satiator Portable Universal Charger- GM

- I will upgrade to lithium batteries in the future once I have the extra money but until then I have to suffice with lead acid gel batteries as heavy as they are... As I mentioned I'll be able to vary between 24V/48V no prob but I did notice a few places suggesting that it was possible to go as low as 10V- 12V... If that's possible, I would love to be able to make it 12V/24V/48V... I know the slower but longer duration will be really useful for indoor use where speed is not the most important thing, precise control is...

I will control the various voltages by 2# 3 position (4 if 12V's an option) High Voltage Switches, 1 at the battery/ 1 at the throttles... The battery switch is keyed to prevent unintentional changes/use. The switch changes wiring patterns/voltage options going basically Off/(12V?)24V/48V.

Assume that I will have my own directly wired charging circuit/bms for the SLAs but I will include a new integrated lithium charge circuit & add an appropriate BMS whenever I change battery chemistries but for now I will use SLAs & the charge protection circuits in my charger... If so, can I get away without a SLA BMS right now by just being responsible not to push beyond safe limits? Or is that a disaster waiting to happen? As always, money is tight so I'ld prefer not to waste the money...

Should I get the battery harness available from GM or stick with my existing SLA harnesses? Do I need any adaptors?

I will be using my own 12V & USB accessories wired appropriately to the batteries & their controls to my control panels. I will have voltage specific resettable fuses wired in....

2# 24V Thumb Throttles- GM
2# 48V Thumb Throttles- GM
2# 12V Thumb Throttles- GM
1#.3 (or 4) Position (high voltage?) Switch- ideally keyed- GM?

There's 2 or 3 throttles grouped together on each of the 2 control panels (left/right) with a 3 or 4 position switch that switches between Off & the (12V)/24V/48V throttles (arrangements isn't important) but I prefer a keyed switch for security.

I know the MP5 comes with a throttle but is it better to buy each throttle separately or as part of the kits I am already buying (no option I think)... I haven't seen a 12V throttle on GM though... Is there package deals to get all the throttles? Assuming that everything is wired correctly, any reason why this won't work?

Given my intent to use all GM products (wherever possible) do I need to be concerned about interconnectivity? Do I need any adaptors? Or will everything just plug nicely into everything? Is any welding/soldering needed? I am not remotely coordinated enough to solder/weld anymore!

1# or 2# Bluetooth Adaptors- GM
1# or 2# MP5 USB Programming Cables- GM
1# or 2# V3.0 Cycle Analyst w/ V3 Shunt & w/o Thun

Alright... I have a windows 8 touchscreen tablet w/ dual boot Android 4.4 & a HTC M9 Android 4.4 cell phone; both with Bluetooth 4 I think... Each are wired into the entire system... I like the idea of CA3 even with controls via Android/Bluetooth but I want to confirm there is no conflict between the 2... I also need to know if I need 1 or 2 Bluetooth adaptors & CA3 systems?

Assuming I have CA3 & Android/Bluetooth, do I need to get the USB cable? I know 1 is offered with the kits but is it free or additional cost & do I need it given the prior info? If I do need it, do I need 2 or can I get away with 1? Also, I don't intend to have gearing/freewheel (I got direct drive for a reason), so I don't see any reason for the THUN option... Am I overlooking something?

4# 8"/10" Cantilever Unitine Suspension Compound Hybrid Kingpinless Casters
8#/16# (2 or 4 wheels per caster) 1"x1" Re-enforced Peumatic Tires on Aluminum Wheels
All Ceramic Bearings
4# Suspension Springs

I doubt I need to go too much into these... This vehicle is a 6 wheeled design powerchair, so there are 1 caster per corner & 2 drive wheels between the front & rear casters. They are custom made casters between 1,300-2,600lbs per; high speed, low maintenance- sealed, casters with moderate rake/trail & no camber with pneumatic & polymer suspensions paired with separate spring suspension (required for stair/curb/unstable surfaces)...

The tires are flat proof Nobby tread tires with 3 continuous valleys/4 ridges (tempers caster flutter)... It is probably overkill but... Considering a 6 wheeled powerchair has never gone more then 20km/h & casters/ caster flutter are the reasons that nobody has... In fact, 99.9% of casters are not safe above 3km/h & lower if not manually propelled!

The few who have tried ended up going for rides nobody wants!!! Casters tend to lose contact with the ground as speeds increase & when that happens the aerodynamics of it cause the caster to go out of line with the direction of travel... When this happens to the vehicle while at speed & with high directional inertia, it's then suddenly flung in an opposing direction.... Typically that means the vehicle flies while doing barrel rolls & is typically a fatal crash.

So like I said, overkill is somewhat warranted here, especially the suspension & tire load capacity! The critical parts are ensuring the casters remain in contact with the road surface & the system can handle the enormous g-forces generated during abrupt deceleration!

Technically there are only about 40lbs unsprung, max 350lb sprung weight (with about 300lbs of that actually sprung, sprung weight) but under high speed that multiples very quickly! I am expecting about a total 7,500lb to 15,000lbs (max 10,000lbs to 20,000 depending on configuration) combined load capacity... Afterall, I don't have a death wish... I may add adjustable dampers to each caster depending on flutter presenting.

The seating system isn't really important here... & right now I can't think of anything else...

Sorry about the length... I am kind of picky about being clear, comprehensive, etc... But I am definitely not skilled in brevity... Thanks to all who bothered to read this & I look forward to hearing your opinions, thoughts, ideas, concerns, etc...

I am just waiting on the answers to this & I am ready to bite the bullet & buy the stuff from Gary at GM but I want to get this right the 1st time...

BTW- anyone know what the current coupon/discount code(s) are?

Adam

& that's again for fixing my account whomever did

[Bikemad]

There are too many questions in your post to try and answer in one hit, so I will simply reply to some of the more obvious ones in a simple list format:

• Front and rear MP5s should both have centred rims.
   
  
• The MP5 controllers are changed between forward and reverse by using a simple single pole on/off switch, but if one wheel is fitted in the opposite direction to the other (mirrored) it would be better to change its direction by swapping the Green and Yellow Phase wires and the Green and Yellow Hall Sensor wires on the controller connections as it would allow the cruise control to be used, as the cruise function will not work while in Reverse.
  (I suspect this might also apply to the Regenerative braking too but I haven't tried it)
   
• 203mm brake discs should fit the motor but the caliper fixing onto the frame will obviously have to accept the larger diameter brake disc.
   
• Magic Pies will not run on 12V battery packs as the low undervoltage protection value cannot be set low enough.
   
• BMS is not required with Sealed Lead Acid Batteries, but you would have to reprogram the voltage settings in both controllers each time you change the battery voltage if you want to use the low voltage protection on both 24V and 48V.
   
• The 48V throttle will work fine on 24 or 48V but the battery gauge LEDs will show empty on 24V. A separate voltmeter might be the best solution as connecting more than one throttle to each controller would be a real pain to implement.
   
• You will probably need to do a fair amount of soldering with this project as it is not going to be a simple plug and play installation by any stretch of the imagination.
   
• Both brake switches will need connecting to both controllers
   
• The USB cable should not be required as the Bluetooth can be used for programming the controllers.
  Two Bluetooth devices should enable each wheel to be selected by changing the Bluetooth device within the app
   

My biggest concern is that the direct drive 26" wheel will not produce sufficient torque and low speed control to provide the accurate slow speed steering and controllability that you would require in confined spaces, and I don't suppose they would be able to lift 28 stone up a curb either.

Take a look at the 4x4 16" Magic Pie which has twice the power and a lot more usable force per wheel due to effective torque increase that the smaller 16" wheels produce.

Alan
 

[AdamB]

Sorry for the delay... Life got away from me... Anyways, Alan thanks for answering so many of my questions... I really appreciate it! Don't stress about having to answer in any specific way; whatever you do, I am sure I'll be grateful & be able to figure it out! I am not picky & I am just grateful that you took the time to answer at all... I have already learned so much from you, this forum is very lucky to have someone like you to help us Noobs out... So thanks...

Unfortunately, your post also induced some more questions... Sorry... I used a numbered bullet point format this time, hopefully it will be easier to read/answer

So...

**1) The MP5 rear & front motors both have disc brakes & are centered... So now I am even more confused on which to get... Is there any other differences at all? Which would you suggest I use?**

*2) This may be stupid but assuming I mount the drive wheels (MP5) side by side, does that mean that 1 wheel needs to be oriented in reverse? I hadn't planned to do so but it wouldn't be the 1st time I transposed or didn't transpose something that needed it...*

*3) Can you suggest an adaptor to fit said rotor on said vehicle? Assuming I use chopped up bike frames, what type of connector do I use? How do I know the bike frame I choose will accept said rotor?*

4) No prob about the 12V, I had assumed I couldn't but then I saw something that said the MP5 had a voltage range of 10V to 60V & I thought maybe it was possible...

5) Alright, so no BMS required... I figure I'm fine there as I have other ways to control charging & overdischarging... I am assuming that I can control voltage selection through either cycle analyst, Bluetooth or (last resort) the USB adaptor on the road...

**6) I am not tied to multiple throttles, I just assumed it was the right way to do it... So assuming I'll use 24v & 48v, what is preferable a 24v or 48v throttle? If it matters, I'll probably stay in 24v mode for 80-90% of the time & just use 48v when I want the extra power/speed. Would it be useful to say use 1 of each (I.e. 1 24v & 1 48v throttle? Then I'ld get the advantages of both? Or is that a bad idea where I get all the disadvantages of both?**

7) Sorry I forgot to mention that though I am not capable of welding/soldering anymore, I knew there will be some required & so I hired someone else to do it! I just was hoping to minimize it because it's not cheap to hire someone to do...

** Huh? Both brakes need to be wired to both controllers? Why? I certainly didn't intend for that, I want to be able to separately control acceleration & braking on either side... Is there a way to avoid that? If not, does that mean I need to buy 4 brake wire sets (2 per brake instead of my intended 1 per brake)?**

**9) Great, so I don't need the USB adaptor but I need 2 Bluetooth adaptors. What about cycle analyst? Do I even need it with the Bluetooth? I won't use pedlec, but I assumed I needed CA for the always on heads up display (do I need 1 or 2 V3 CA)?**

10) The original design called for 4 drive wheels, I.e. 2 drive wheels on either side... But I can't afford 4 motors right now... Heck, if I had the extra cash, I think I may be better to focus on switching the batteries to lithium type instead of lead acid... I figured at some point in the future, I will upgrade to the 4 drive wheels but until then that's just more money then I have. It may well be that 2 drive wheels are not enough but considering most motors powering powerchairs are less then 1 quarter the strength of just 1 MP5, I hoped it would be OK!

11) In terms of control, well that is just something I will have to deal with once it's built... I am sure I'll figure out how to make it work...

12) I have seen the vehicle you are describing, but what you don't know about that design is that stability & indoor handleability (relative to 6 wheel design) are compromised... Actually, 4 wheeled designs are explicitly counter-indicated for indoor or dual use chairs... However said vehicle is why I originally planned to use 4 drive wheels.

*13) However, I am not innately tied to the 26" size, is there significant value to going with a 16" vs 26"? A big reason I didn't go with the smaller & thus cast wheels is I understand they can not be repaired, balanced, remade with different rims/wheel sizes, etc. To be honest, I thought they were all the same except that the larger outer wheel dimensions allowed a slightly higher speed but that if in the future I remade the wheel with a smaller rim/wheel, I'ld get the effects of using the smaller size without being forever married to 1 small & unusual size! Am I out to lunch here? Are there actually innate differences between the smaller & bigger wheels?*

**14) I still don't know what type of tires the MP5 uses...**

*15) I still don't know if I am better to chop up some bike frames or just custom build a frame...*

16) In terms of the loads & forces involved, the vast majority of it are on the corner casters, while some will be on the drive wheels, just about all the extreme forces are on the casters (why I designed such extreme casters).. Also the specified loads are the max, typically it will be a lot less then that...

17) I can also assure everyone that I won't be personally doing the test driving but that the person who does will be wearing appropriate safety/protective gear & it will be on a closed course! I am not willing to risk anybody's safety or welfare just to satisfy my own needs/curiosity!

Anyways, thanks again for all the help so far, you have really helped me figure a lot of this out & I am very grateful for all your help! Sorry about the endless questions & length... I'll leave it here for now but I am really appreciative of everything you have done... BTW- I marked the important numbered points with asterisks, so if you prefer to only answer select questions, those are my 9 important questions... Also I marked my top 5 most important questions with double asterisks. Thanks again!

Adam

[e-lmer]

The main difference between the front and rear wheels is the derailleur freewheel.
It doesn't sound like you intend to pedal it so the front drive Magic Pie will be fine.

You would mount both wheels identically, or you could mount them mirrored, but
would have to permanently reverse one so they turn the same direction.

You could use any bike frame, you just need to make sure that the disc brake mounts
correspond to the diameter of the brake disc.

The controller should auto-detect the battery voltage every time you connect the power,
so you would not need to program it, BUT if you connect an uncharged battery pack you
risk running the battery dry, which shortens it life (or destroys some LiPO batteries)

I think that was to both controllers as in each one needs a brake connection.
Note: The brake switches are not proportional as far as I know, simple on/off switch.)

The tires are up to you, basically any mountain bike tires are ok.

If you cut up bike frames, then you have the difficulty of attaching them to your chair,
it seems it would be better to design a frame to fit your use instead.  The biggest advantage
I can see to that is you could eliminate torque arms by having a slotted steel plate bolted on
to an aluminum frame.  The brake calipers would be a little tricky.

Consider including  a removable roll bar assembly for outdoor use.




 

[Bikemad]

**1) As Elmer suggested, the front would probably be the obvious choice as it only requires a 100mm wide dropout.

*2) Mounting the wheels in a mirrored arrangement would allow both brake discs and motor wires to be on the inside of both wheels.

*3) Using a rear swinging arm from a disc brake equipped full suspension bike would allow easy wheel/disc brake mounting and also allow the addition of suspension too.

4) The MP5 has an advertised working voltage range of 20V to 60V. It will not work below 20V, however I have run an MP4 on a pack with a maximum charged voltage 63V.

5) The Cycle Analyst could be used to prevent overdischarging of the battery, but the low voltage settings would need to be set according to the battery voltage being used.

**6) 48V throttles would be best. Using a 24V throttle with a 48V battery will cause the battery gauge LED unit to become very warm and liable to failure. Alternatively, you could rewire the battery gauge section of the throttle units to the 24V battery which remains connected to the motor's ground connection and just monitor one of the two batteries when they are connected in series to give 48V.

7) You will need to plan ahead and try to ensure that all soldered connections can be carried out in one session to reduce the cost.

8 ) Most electric bike safety legislations require the power to both motors to be cut if either of the brakes were applied.
Unfortunately, if your vehicle is going to be steered solely by throttle and brakes, complying with this safety requirement would not be practical.

**9) As long as your controllers have the latest upgrade you should not need the USB adaptor. Using 2 Bluetooth adaptors should allow both motor controllers to be monitored and easily adjusted via a suitable smartphone.
If the battery voltage is not set correctly in the controllers you will find that the regenerative braking will not work properly. Bluetooth would definitely be needed to adjust the voltage settings to suit the battery voltage, in which case, you would not need a Cycle Analyst. The Bluetooth display function should also provide a voltage reading to allow the battery voltage to be manually monitored.

10) Steering via throttle and brakes with 4 fixed drive wheels is going to be very poor. If you were going to use four motors you would need to incorporate some form of steering mechanism. Although powerchairs motors are lower powered, the gear reductions that they tend to utilise will significantly increase the output torque of the motors.

11) I am still not convinced that the Magic Pie 5 will produce adequately controllable low speed torque, which will make manoeuvring at slow speeds very unpredictable. The geared motors on the powerchairs would not suffer from this problem.

12) The 4 wheel drive vehicle in the previous post would be far more controllable for indoor use than your proposed two wheel drive Magic Pie 5 as the vector controllers are not very good for low rpm speed control.
Check out this video to hopefully see and understand what I am trying to explain.
With my 26" MP4 (same motor as MP5) the regen will not engage unless the bike is moving faster than ~6.5 mph, and the electromagnetic braking automatically disengages if the speed drops below ~3mph.

*13) A smaller cast wheel should be much stronger, produce far more directional force and is unlikely to require any repairs to the rim. As the motors will be turning at the same maximum rpm, a larger diameter wheel will provide a higher speed, but less directional force.

**14) the tyres will obviously depend upon the wheel diameter, but as Elmer has already said, the 26" rim will accept most 26" bicycle tyres.

*15) You could possibly use a pair of front suspension forks to mount the wheels into a custom frame and simply place a long 10mm bar between the two dropouts to align the wheels in the straight ahead position before finally fixing the forks.

16) The majority of the load should be on the driven wheels not the castors, or you are likely to lose traction completely on uneven ground. The castors should only be required to prevent the vehicle from tipping forwards or backwards and to prevent it from rolling sideways.

Alan
 

[AdamB]

I'll go into more detail later (too tired now) but thanks for the replies...


The big thing I was going to say is I'm exempt from all legal e-bike/vehicle rules...

If you check the Ontario DMV. (I know it's mouth called that but I'm tired & remember the term) or google that & mobility devices (easy term), you'll find that mobility devices are defined as pedestrians & either use these sidewalk or the side of the road going *against* traffic (Yup, that's correct, I often end up in head to head confrontations (nothing serious) with cyclists & the cars (more serious)...

Obviously that doesn't change the laws of nature that still apply but the government has no say in this area, rightly or wrongly!

Anyhow, night

Adam