hydraulic brakes, regen and cruise(photos and video update)

[Andrew]

Can it damage the MP motor if braking whilst the motor is still running. for example, i'm thinking of getting hydraulic brakes (front and back) if I did brake whilst still holding the throttle would this cause damage or heat build up? .  i like the idea of having regen and cruise being button operated but also understand that cruise not cutting out automatically when lever braking could be an issue?

Andrew

[GM Brazil]

I know that some (fuel) bikes have a hydraulic pressure switch used to turn on the brake light. You could try to use one. The other alternative would be use your horn button to activate regen and deactivate the motor when you brake and use it in such way that it became an instinctive reaction.

I do not know for sure if braking would damage the motor but I know for sure that trying to brake at high speed with the motor running in auto-pilot for example could for sure damage your bones and teeth  

[MonkeyMagic]

Bruno man where have u been !!!!

Whats up

[Leslie]

No usually it wont blow your motor, and yes it will build up heat. But you will see your power bill and brake pad replacement frequency increase.

Any power wasted in this way will create heat between the brake pads and rim, and in the motor and controller, battery and cables..

I don't use cruise control but I think you could figure out a way to have cruise control button switching the brake signal over to the brakes switches and the brake switch, switch the brakes back over to the regen switch.

This way your regen would always be operational off the button and the brakes may just get enough time to disable the cruise function.

There is a slight delay until regen cuts in so you will prolly only notice the cruise function coming off line.

A latching relay may do it easy but they use a lot of current in spikes and you only have 5v to control the switch.  So a flip-flop circuit would be more efficient.  

[Leslie]

I hope you have a good torque arm too Andrew.

I forgot, but running a motor at full power and hitting the brakes at the same time is unhealthy to your dropouts.

Not sure about this either but I think cruise control delivers full power but like speed scale may only limit RPM.

[Leslie]

Idea!

If you connect the brake switches to the controller through a very small series capacitor it will allow a full volt brake signal pulse to unhook the cruise control but not enough to continue regen.

When a series cap fills up to full it blocks DC but allows at one point for a split second, depending on the farad of the cap, a closed connection, this creates a pulse and a dead drop in current to anything you wish to pulse.

Then just leave your regen button as is.  Parallel with no capacitor in circuit to the controller.

IF the cap is small enough it should not allow regen to take hold and discharge very quickly ounce you release the brakes.

[Leslie]

Try this.



In green is what you have already and in red is what may do the trick I bet it will.

Shouldn't have to change what you have already setup in any intrusive fashion..

Use a bipolar cap so it doesn't matter what direction you face it (idiot proof), and maybe something in the value range of 100pf and move up by adding 100pf capacitors in parallel.

The bigger you make the cap the longer it takes for the pulse to drop and regen may kick in, and the longer it will stay charged blocking the brake signal after the brake is released.

It should take you 4 minutes and cost you 50c, and I am guessing, but pretty sure it would be harmless to your controller to try it out.


Edit:

Opps! You would need a large ohm small resistor to burn the the current off the cap.  The cap is tiny, so it should drain very quickly with a resistor that will only allow lower than 1ma to pass at 5v.

I will have to get my capacitor Faraday math out and measure the current required for the brake function.

But this is a good starting point.

Edit 2:

Ok! I will try this out before the weekends up.

[Leslie]

And there is a High brake and low brake pad on the Magic Controller PCB.

Nobody to date has tried these AFAIK.

The difference between high brake and low brake could be the volt drop of a diode or a resistor.

We will know soon enough.  Ill play around when I hard wire my bike over this week end.  

[Andrew]

hi Les, unfortunately i'm not gifted like you are in the mysterious martial art of electronics, so it will have to be down to you to try your above suggestions. I might fit hydraulics brakes and have the regen relocated to button operated only.  would it be possible to have a button activate regen only when actively pressing a button instead of as an on/off switch which has to be pressed again to de-activate?

[Bikemad]

Andrew,

The horn button will work fine as a regen switch, but it means you have to use your left hand each time, but it shouldn't be a problem unless your using arm signals to indicate a left turn.

Alan
 

[Leslie]

hi Les, unfortunately i'm not gifted like you are in the mysterious martial art of electronics, so it will have to be down to you to try your above suggestions. I might fit hydraulics brakes and have the regen relocated to button operated only.  would it be possible to have a button activate regen only when actively pressing a button instead of as an on/off switch which has to be pressed again to de-activate?

There is no reason why you cant use one brake switch for regen and unhooking cruise and motor power.  One brake switch is good,

It has been raining heavy the last few day and I needed to ride the brakes to keep them working properly in the wet. I can see why some one would like to be able to run the motor while operating the brakes.

But you could also just hook all the switches you want up the the brake switch wires.  Have the brakes and button switch happening.

[Bikemad]

There is no reason why you cant use one brake switch for regen and unhooking cruise and motor power.  One brake switch is good,

Ahh, but you've overlooked the obvious reason:

I'm thinking of getting hydraulic brakes (front and back)

The levers for hydraulic brakes are not usually fitted with switches and therefore cannot connect easily to the existing brake switch wiring. But it might be possible to attach an Ultra Miniature Microswitch to the underside of the brake lever housing which could operate when the lever is pulled, similar to the current mechanical brake levers.

Unfortunately, without seeing exactly how the hydraulic levers move, it's difficult to come up with a suitable solution.

Alan
 

[Leslie]

Well looks to be plenty of things you could play with there.

Ahh when gluing my aluminium reflector to the aluminium heat sink I used thermal glue and this resin 2 pack metal glue.  OMG it works very well on aluminium.

You could glue a micro switch or two along the lever somewhere would be fine.  Make it not stick out too much so you don't need to squeeze it in an emergency stop situation.

Or choose to press location on the brake lever, Stuff like that for fingers would work good, for unintrusive controller functions or compatible with braking functions.

[Andrew]

Quote by BIKEMAD = Unfortunately, without seeing exactly how the hydraulic levers move, it's difficult to come up with a suitable solution.









Short video of lever
http://www.youtube.com/watch?v=jpyctVgDyUo

The lever distance from your fingers/grip is quite adjustable, along with the amount of lever movement. So adjustable for short/long fingers and how sensitive you want your braking to be.

The lever at the moment is at its widest point (10mm gap)

Andrew

[MonkeyMagic]

Hey mate

You could install a microswitch in there but it would risk molesting those beautiful levers
And installing one on the side of it would be mega fugly.

The brake lever switches are just tiny microswitches located just inside the hinge.

Not sure if you are using a horn, but I would just use that switch. I have a few handlebar buttons so have one regen button on each side.
When I use it, I tap the ebrake button, then mechanical brakes, then apply regen with the brakes using my thumb its really easy

My only problem I have ever encountered is having dual drive, when hitting a ebrake switch quickly to turn the cruise off, sometimes 1 wheel keeps going... But you just tap the button again, I couldn't see it causing an accident.

Hey I have a question, in experience guys - do you find the quality of hydraulic brakes differ brand to brand? Like if I replaced my front cable disc caliper with a hydraulic setup, is there anything I should look out for quality wise?

MM