USB charging socket idea

[Haku]

When I'd set my mind on getting an electric bike at the beginning of this year the thought of having access to a high capacity battery gave me a few thoughts, one of them was that it would be nice to have a USB socket somewhere on the bike to charge my mobile & mp3 player, no connection on the data lines just the ground & 5V lines.

Has anyone else thought of this or actually added one?

dimensionengineering.com sell a neat little 5V 1A output Switching Regulator that can take up to 30v input which would be ideal for providing the power for the USB socket on 24-26v battery bikes.

I like dabbling in electronics and if I get stuck I know an electronics engineer who can help on the more complicated things so doing this wouldn't be too difficult for me, apart from likely voiding the warranty by modifying any of the electrics on my new bike which I'm not really prepared to do at this time.

 

[coops]

Hi Haku,

I've thought of it, but that's as far as I got! I'm not that experienced with electronics, but there are others here who are & may be interested & able to help: everyone's got some gadget these days, haven't they

I don't know if my concerns are valid, but I'd be a bit worried about possible damage to a phone/mp3 player due to incorrect voltage or something.

Out of interest, I don't suppose you own an Iriver mp3 player & visit the misticriver forums, do you .

Stuart.

 

[Haku]

Yes I do, and yes I do

I have two iHP-140 units, original one I bought almost 3 years ago and a 2nd as backup I 'frankensteined' from 3 broken units and works perfectly. I only charge them from USB now as it's so convenient and I'm almost always near a computer.
I also charge my mobile and my Archos AV500 from USB all the time now, the list of devices that can charge this way is huge and still growing.

 

[coops]

I thought there couldn't be two haku's! nice to meet you here! Small world eh? I never posted on misticriver I think, but your stereo mic mod was a great idea which I used to make my own dabble in electronics indeed! You're too modest .

I've only one iHP-140, doesn't USB charge as it is, but at least its rockboxed now . Since you've modded yours to charge via USB (or was there a special retractable cable that could do that, I've forgotten), you're half way to the ebike USB charge mod!! Would that be the first do you think?

So now ebikes too... great minds think alike, eh? Glad you're enjoying your Urbanmover36 & hope you get somewhere with this mod.

You got speakers on your bike yet...?

Stuart.

 

[Ian]

Sounds like a perfectly feasible idea Haku, on some bikes the charger socket is always live and could be used for power take off without the need to modify anything. A switching regulator would efficiently convert the voltage, the current drain from the battery being almost negligible.

 

[coops]

Sounds good then .

Haku, I think you're right not too void the warranty though; best wait & see that the bike is reliable first before you start .

Happy cycling in the meantime!

Stuart.

 

[Haku]

The stereo mic mod produced some interesting results I found but couldn't beat a true stereo mic because of the stereo separation & matched pickups. I did recently install two microphones into a bullet camera again the stereo effect wasn't that good though. I haven't modified my iRiver players to charge from their USB sockets because doing so means you couldn't play music and charge from USB at the same time as it would go into connect mode, I simply took a USB cable and attached a power plug to it which fits my H140/mobile/AV500. Cables like that can be bought pre-made, there's even a retractable version.


Back to the bike, as I have a lithium polymer battery the charging socket isn't 'live' like some of the NiMH types but I have figured a way of taking power from the battery without voiding any warranty or doing anything permanent.

The base of the Urban Mover batteries has two inset plates for outputting voltage when the switch is turned on, the bike has two large springed contacts that press against the battery, so there might be a way of putting a couple of small contacts inbetween the battery & bike to draw power from.
The only thing that worries me about doing this is if the small plates I put inbetween the battery & bike don't make good enough contact and couldn't handle the power going through them for the motor.


No speakers yet, but I did turn the reflectors into lights by using ultra bright LEDs the police have seen me with them at night and haven't stopped me

 

[coops]

I wish I could be more help Haku, but small wiring jobs are the current limit of my skills (no pun intended) . You may have noticed that this is perhaps the first time this has been proposed here and so a bit novel, but I'm sure there are some who could benefit from it, myself included, and who have the knowhow to implement it (errr, myself not included).

There has been a certain amount of mods to bikes going on lately (check out the Project Q bike & T bike if you've not seen them, and if you're interested there's more ideas in What makes an efficient on road e-bike?) so who knows, mods could take off!

Stuart.

 

[flecc]

Given the small current you want to take off Haku, could you organise take off contacts in a position that lifts the current from the spring blades that hold the contacts. The take off contacts could have a piece of light foam backing to use the battery weight to apply sufficient pressure for the take off of current, while not disturbing the relationship of the battery with the main contacts.

 

[Haku]

corps, I did do a search on the site but found no mention of USB anywhere

With the prolificness of USB powered devices almost everywhere these days I'm suprised no ebike company has added such a socket for charging mp3s/mobiles etc., perhaps because of the problem of where to keep the USB device during charging, my solution would be either a retractable extension wire so the USB device can sit happily in a pannier bag or a small bag slung from the frame.
Also would you 'hardwire' the USB socket in so that it always outputs voltage, or have a switch for it, or only output voltage when the main bike is switched on. With the relatively small amount of drain a 5v output switching regulator would use when hooked up to an ebike battery but not delivering any power it might be ok to have it permanently connected, but I wouldn't risk it just in case you completely drain the battery below it's safe levels (especially lithium ones).
Lastly waterproofing the socket, I haven't seen any USB sockets that have waterproof covers but maybe there's some generic waterproof socket cover that would do the job.


flecc, I'm not sure I understand what you mean, other than having a plate in between the battery+bike I thought of just wrapping some wire around the round spring terminals as a first test. I've got to take a closer look at the terminals on the battery+bike and see how much space there is (if any) when they're connected.


It's great to see ebikes being modded to go beyond their original design, I always like looking at something and seeing if I can improve it for my needs/wants, especially if it's electronic

 

[coops]

With the prolificness of USB powered devices almost everywhere these days I'm suprised no ebike company has added such a socket for charging mp3s/mobiles etc.,

Yes, though maybe with ebikes being still a relatively "developing" industry and a niche market, they haven't quite reached that level of sophistication: many companies seem to have enough problems just with the basics!

There are some simple but effective tips on the forum, somewhere, for waterproofing specific bike parts, and some details on flecc's site in case that's useful? Maybe not exactly what you need, but may give you some ideas.

It's great to see ebikes being modded to go beyond their original design, I always like looking at something and seeing if I can improve it for my needs/wants, especially if it's electronic

I thought you'd like that ...just wait for your warranty to run out before doing anything drastic! plenty of time to get a feel for the bike & what you might like to "improve"! Keep an eye out for the T-bike update coming soon .

Stuart.

 

[flecc]

Hi Haku, I don't know the UM battery, but if the contacts are on spring blades like those on the Giant Lafree Twist bikes, there's room to mount an ntermediate plate between battery and bike with contacts that touch the blade arms without anything going between the contacts themselves on bike and battery. For a small current the blade arm contact should be sufficient. To apply some pressure to that additional contact point, a bit of light foam rubber on the back of the additional contact plate would do the trick.

Difficult to explain more clearly than that.
.

 

[Haku]

Re-reading what you've written and taking a closer look at the contact setup on my bike I understand what you mean, basically add in a couple of smaller contacts next to the main contacts for drawing the power for the USB socket ?

There looks to be a few mm gap between battery housing and bike which would indicate enough space for some sort of contact setup, as well as the battery contact plates being much bigger than the bike's springed contacts, and I've just this second whilst typing worked out a really simple solution, springs that sit around the main contacts so there's little chance of the additional contacts accidentally short circuiting or getting in the way of anything.

Apart from a USB socket, what's more useful about getting power from the main battery is using it to power lights, that way I can use enough LEDs to give cars a taste of their own 'dazzling' medicine

 

[flecc]

That's it Haku, you've got it, I thought there'd probably be enough space there judging from others using similar contacts.

Glad it's working out ok for you, and that you're looking forward to a dazzling future for motoring!
.

 

[Haku]

I successfully tapped into the power of the battery this evening

Using some welding wire I made a couple of springs with diameters slightly smaller than the bike's springy contacts, so when they're put on they grip tightly to the contacts.
Soldered wire onto the springs and hooked up an Adjustable Switching Regulator from dimensionengineering.com tuned to get pure 5v which easily charged my mobile, iRiver mp3 player and Archos AV500 PMP (though not at the same time).

Couple of oddities was that I had to turn the voltage up on the regulator so with open circuit it outputted about 5.8v but under load it was a steady 5.07v, this with an input of 29v. It also got quite warm but I think that's ok, they can run in parallel to output more amps so wondering if I should get another so they don't heat up.

Now the tricky part of working out how to have a waterproof socket somewhere and powering LEDs for lights, bearing in mind about the voltage difference of open and close circuit with one of those regulators, especially when the white LEDs need 3v and the red only 1.2v.

 

[flecc]

Those regulators do tend to get warm Haku, the ICs getting to hand burning level without failing, and can stand quite a lot. As long as you don't load it with too much more it should be OK. Can't really help at a distance on the lighting setup though, as there could be a bit of trial and error about that.

Given the lack of waterproof connectors, the only suggestion I can make is XLR or NTC in line connectors. The plugs on those have long close fitting shrouds over the pins which overlap the socket. If you put a thin rubber O ring or a suitable small rubber band onto the socket at the shoulder, the plug shroud would butt tightly to it or even just over it, sealing it quite well. The cable entries to those have rubber sleeves, and silicone rubber sealant can perfect the sealing of the entry.

They have three wires allowing two differing voltage paths and a common return. Here's a Maplin page with a plug shown.
.

 

[Haku]

Looking for waterproof plug/socket setups on maplins/cpc/farnell sites I did see the XLR plugs pop up often but they look rather large & bulky, interestinly the UM li-pol batteries use a 3-pin one of these connectors to charge, with a screw-on cap to cover the socket from water/dirt. That is one option I can use so long as I use one with a different amount of pins, wouldn't want to be able to plug the bike charger into the custom 5v output socket at all.

I'm going to grill my electronics engineer friend over getting the right voltage for the LEDs and if he knows any small-ish waterproof plug/socket setups.

A waterproof switch is also going to be needed for the lights though to prevent them turning on every time I switch the battery on, plus some way of mounting it as well as the voltage cut-down components to the handlebar.

 

[flecc]

Yes, that's an NTC type, very popular in the Orient. Powacycles also use a three pin version on their batteries for charging.

Waterproof switches are always a problem. Maplin sometimes have waterproof covers for some of their switches, and there's also the possibility of an old type motorcycle switch. Here's one you can try: switches
.

 

[Haku]

Thanks for the link to the switches, the simple on/off one looks like it could be ideal for lights. I haven't gone off the idea of adding the ability to charge my mobile/mp3 from my bike, I've just been very busy with other stuff recently but still thinking/planning what & how I'm going to do it, using a 4-pin NTC type (so it can't be confused with the 3 pin on the battery) has given me the the idea that 2 pins could be used for 5v out for charging mobile things whilst the other 2 could have the full battery voltage output, which would leave the possibility open for using a step-down regulator set to 12v for powering devices that need 12v, or indeed any other voltage.

At the same time as adding the aforementioned ability I'm also going to power the lights off the main battery, presently I have 3 high brightness LEDs in the front reflector which work suprisingly well but I have a bag here with over 60 of them in... my plan is to mount up to 14 in the reflector, two half circles on either side of it.
Now the bike has a pannier rack I've had to re-think the back light so I bought some red reflectors that are approx 1" by 4", as a test I mounted 4 extreme brightness red LEDs in one which make it glow really well from all angles.

One of the more experimental fun ideas I've had since getting into playing around with miniature video cameras & LCD screens etc. is to put a rear-view camera on my bike with a small screen on the handlebars just got a cheap pocket tv which runs off 5v fine and have figured out how to easily attach it to my handlebars using a spare reflector mount. As I don't have a camera that mirrors the image I'll have to find a small mirror instead, as I've got nothing planned for Monday I'm going to try and set this up, should be fun.

 

[flecc]

That all sounds great Haku, but don't forget to leave some juice for the motor.

I'm looking forward to seeing how you get on with that lot, though I'm not too sure about watching TV while riding. You might be tempted to catch up on a program!
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