Sensored Turnigy GT Peace + vid

[blitzwagen]

Hi,

I've finally (it took a long while) got this bike moving under its own steam ! It's the GT Peace 29er with a Turnigy 130kV motor. I've got my take on a 4:1 belt reduction to a disc brake adapter ( thanks Matt) left side adapter with a 160mm disc brake. The disc is offset by 8mm to clear the sprocket.

The motor is driven by a 12 fet infineon using 4110 fets from 4X6s Hyperion lipo's making a 12s 12 amp/hr pack. It's geared for 60km/h and I get about 40km of range. I have it set for about 5kW peak loads.

This bike will wheelie at will from 0 - 30km/h, fantastic fun !

Special thanks to the guru's Burtie, LFP, Matt, Gwhy and Jeremy and many others for their tireless efforts and endless sharing...

[youtube]_wK0YxKIHLo[/youtube]

Hitesh
Cape Town
South Africa.

 

[gwhy!]

Very nice , looks very neat and tidy.
Thanks for the nod

 

[blitzwagen]

Thanks gwhy, although I'm still moulding a glass fiber inner frame covers to hide the battery pack and motor. You guys deserve the biggest nod, I'm sometimes staggered by the level of engineering and sharing on these here forums. I did however forget to tip my cap to the head honcho Miles from whom I've learned a ton.

The only flaw with the drive system is the throttle response from standstill, it's still a bit vicious. I wrote a few curves to a micro controller but it wasn't very successful, what's really needed is torque control I guess.

 

[liveforphysics]

Fantastic job! Sensored on the 130kv HXT motor makes for a really nice setup.

 

[gwhy!]

The only flaw with the drive system is the throttle response from standstill, it's still a bit vicious. I wrote a few curves to a micro controller but it wasn't very successful, what's really needed is torque control I guess.

Have you tried turning the phase current down a bit ?, I found this help quite a bit I aslo fitted a 2 speed ( 50% and 100% speed ) switch into the controller this gave me a lot more control ( doubled the throt resoultion on 50% and made it even more controllable ), hope this helps.

Cheers,

 

[blitzwagen]

I've played with the phase current and it does indeed help but I find that it tames the entire response so that I lose that instant wheelie power that I now enjoy. What I'd really like ...dare I say it.....is a soft start for the 1'st few hundred rpm. I've tried that speed switch but I find that it's too distracting to worry about speed switches when riding.

Maybe I should try a micocontroller that does automatic speed switch switching depending on where in the throttle range you are. So, up 25% throttle, speed limit is 50% after which it's 100% - what do you think?

 

[gwhy!]

I've played with the phase current and it does indeed help but I find that it tames the entire response so that I lose that instant wheelie power that I now enjoy. What I'd really like ...dare I say it.....is a soft start for the 1'st few hundred rpm. I've tried that speed switch but I find that it's too distracting to worry about speed switches when riding.

Maybe I should try a micocontroller that does automatic speed switch switching depending on where in the throttle range you are. So, up 25% throttle, speed limit is 50% after which it's 100% - what do you think?

I know what you mean about a switch when riding I have mine arranged that normal speed is 50% then I have a momentary push button on the other side of the handlebar for 100%, it takes a bit of getting used to for obvious reasons but this have now got me thinking along the lines of setting up a sort of clutch layout ( in line with the throt ) that will change the trot resolution on the fly. I think your idea is better but it would depend how smooth the transition would be between the speed settings as you wont have to worry about having another control where the rear brake is. Please keep us/me posted.
Cheers,

 

[AussieJester]

Very nice indeeed, when the covers are over the side of the frame and you will have a very stealthy
setup...excellent job! Have you seen the slipper clutches Matt is building for the drive units? might
also solve the startup issue?

KiM

 

[blitzwagen]

Thanks for the positive comments guys. AJ, I do think that a clutch would be solution for take off, although I'm hoping for an electronic solution. My next bike is going to be less commuter and a lot more offroad, I think that a slipper clutch will then be a must when landing jumps etc. Gwhy, I'll let you know how the speed idea pans out, with 3 speeds the change from one state to another may not be too abrupt.

I've had a question about the disc brake setup. here's a picture. The caliper needed about 3mm shaved off the corner and the spacer takes it out by 8mm. I don't have full pad coverage but it's enough to lock the rear at 30km/h.
I forgot to mention that I have a nexus 3 speed for the pedal side which makes for a very nice independent drive system because I can always keep up.

 

[liveforphysics]

Thanks for the positive comments guys. AJ, I do think that a clutch would be solution for take off, although I'm hoping for an electronic solution. My next bike is going to be less commuter and a lot more offroad, I think that a slipper clutch will then be a must when landing jumps etc. Gwhy, I'll let you know how the speed idea pans out, with 3 speeds the change from one state to another may not be too abrupt.

I've had a question about the disc brake setup. here's a picture. The caliper needed about 3mm shaved off the corner and the spacer takes it out by 8mm. I don't have full pad coverage but it's enough to lock the rear at 30km/h.
I forgot to mention that I have a nexus 3 speed for the pedal side which makes for a very nice independent drive system because I can always keep up.

This is such a nice build! Loving the nexus in there to help the pedaling. Since you've got a freewheel in there to prevent back-torque from reaching the motor, the slipper clutch would just be to absorb shock between the rate you accelerate the outer part of the front freewheel?

 

[Thud]

Blitzwagon,
nice build. Looks like you are having some fun.

Using infineons should make the start up very smooth & progresive. I would check your throtle & see if its functioning correctly. The infineons I have love hall throtles....but all of my chineese hall throtles are notoriously flimsy. & one of them acts as you describe...more of a switch than progressive throtle.

Keep us posted, T

 

[blitzwagen]

Thanks for compliments LFP and Thud ! This bike has me grinning every time I ride it. The infineon is an order of magnitude better than any open loop sensorless controller, it's just that from standstill, I really have to concentrate to stop the thing from wheeling. Once I'm going it's ok but I do have to be careful. I've tried a few hall effect thumb throttles and its definitely not a fault with the throttle.
I really need a more exponential torque response. I checked Matt's slipper clutch thread and it looks fantastic especially for dirt bikes. I'm going to give my take on gwhy speed idea a go soon.

 

[mwkeefer]

Beautiful build!

I'm going about the same goal shortly (doing 2 bikes at once) but I will be attempting to drive the 3spd rear from the right with isolated freewheels - that will give me 3 spds for both pedal assistance and the motor - otherwise it's looking like it will be very much identical to your setup

Very quiet, clean and straight forward build - how did you install your hall sensors for the Infineon to work with the Turnigy 130kv?

-Mike

PS:

If you wanted - I can write up some firmware to accept your hall throttle and remap it or even add some triggered outputs, so you can start as you say to maybe 20% with Speed %3 selected then above 20% throttle open, kick to 100%. It would take a bit of getting used to but I like the idea better than switches. Do you have some atmel MCUs laying about? Can I get an envelope to you cheap there from the USA?

 

[deecanio]

this bike runs real sweet, more vid please blitzwagon and also more shots of the drive setup!!
Also please post your findings on the throttle side of things, would really help.

D

 

[Goethe]

Very nice build! The sound is wonderful.

You could use a Cycle analyst and let it control the throttle in torque mode. 10% throttle would give 10% torque and so on.
I have ordered a CA-DP and will try this with my Lyen 12-fet.

Edit: You could also play around with the current PID regulator in the CA and see if you could slow it down.

/Goethe

 

[blitzwagen]

Thanks Mike ! I look forward to seeing your bikes soon, especially with the 3 speed Rhs drive although even I'd feel a bit unsafe above 60km/h on a bicycle. It was however my original intention to go that route for which I ordered the TP packs freewheel adapter. After pedaling about with the nexus I decided against it. My gut feeling was that one wrong shift under power would see its demise ( I think that Deec may have already discovered this).
My fears might be unfounded especially once we get this throttle curve sorted. The instant torque hit (shock load) with this motor is *very* impressive and equally destructive.
I've been programming an ATMEGA328 with an arduino, its the language I'm most familiar with right now - will it work for you? I'd be keen to join forces on this. I have a 80-100 Turnigy with a 12 fet on the bench ready for any testing. Oh, the halls were bonded into the stator and no load current at 40V was about 5 amps. Not optimum perhaps? Cruising at 30km/h on the flat draws around 400w (~9 amps) so I think that efficiency is acceptable.

Goethe, I didn't realise that the cycle analyst had this functionality, I just never considered it. I assume that torque control is done by limiting the current from the batteries. LFP is probably the best guy to comment here, from my understanding limiting the phase current will produce proper torque control and not battery current (?) I love the sound as well, a bit like a Star Wars Tie Fighter fly by !

Deec, it really is a jump on and ride sort of bike now. Your early Stinky exploits is what inspired a lot of us. I can almost hold a wheelie for a few seconds, if I don't hurt myself practicing I'll get it on video for you. If you had any doubts, sensored infineon control is absolutely the way to go despite the sensitive throttle on take-off. Although I'm certain that it will get fixed quickly with all the talent on this forum. I wish that these Astros were as easy to hall as the turnigy. I'll be looking at fitting halls to my Astro 3220 shortly. If you have the double shaft version, fitting a disc to the back with magnets would be the easiest ( I wish that I ordered the double shaft )