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Monday, January 21, 2008

Cargo pods that don't suck anymore

I got an inoperable Samsung upright vacuum to use for parts via the Freecycle mailing list a few days ago. It's not really anything special in and of itself, but since I had to take it apart into it's primary three sections (handle, bag area, and base) to transport it home on my bike, I had an inspiration when I saw the bag section sitting there separately. As you can see below, it's about the same width (little more) as the bike seat, and just a few inches longer than the space from the seat to the back of the rear wheel.


This means it would fit nicely in place of my kitty-litter-pail cargo box, when I eventually start making one of the bikes look stylish and neat, instead of sloppy and junky. I haven't done that yet because cool-looking stuff is asking to be stolen, and I also don't have a final idea what this will all look like, since I don't even know what motor/batteries/etc will be like. Once I have an e-bike that works, and a job I commute to with it that I can take it inside with me or have in a *secure* area not publicly accessible, I'll be able to get as stylish as I want to, within the limits of what I find recyclable from other things. It's got a lot of space inside, perhaps not quite as much as the kitty-litter-pail cargo box does, but enough for some things, and I could put more than one on the bike. Say, one on top and one on each side down by the rearwheel axle (better balance the lower they are).

I've also got a Dirt Devil upright that has a working motor, but a fused-ended brushroller (looks like it got so hot from friction it melted the ends around the bearing assemblies, and won't spin anymore). It too has a potential cargo-container for a bag-body.


They're both ABS plastic, which means they shouldn't warp in the Phoenix sun in summer, (unlike the scooter casing which is just polystyrene) and they shouldn't just break when I crash (which will happen; it happens to everyone eventually if they ride the roads long enough, usually more than once). They're also easy to modify, because I can glue other things to them (I usually use Plastruct glue for this type of work, as it melts the pieces together at the join, making them one piece), or drill and bolt-on things. They're reasonably weather-resistant, once I seal up the holes hoses and cords went thru (they are meant to hold very fine dust inside as you vacuum your house, after all).

The teal one (Samsung) is my favorite, because of it's shape mostly, though I also like the color. Doesn't matter what color it is now, as it will be painted fluorescent colors later, after I can find paint for the whole bike. I've even got the option of mounting a motor (if not too large) inside the large end of the case, and running the shaft out the side, just like the original vacuum motor did. This would reduce any motor noise, and keep dirt/etc out of it. Unfortunately, it'd also hold in the heat, unless I added a cooling fan and ventilation, which might defeat the whole enclosure idea. The end where the handle used to attach is perfect for an integrated taillight/brakelight, and I can add the turnsignal/marker lights on either side of it externally. All I have to do to make it lockable is drill a hole for the lock off the scooter (from it's battery compartment cover), and make a slot for that lock's swingarm to engage with inside the case. Not much of a lock, but it will keep honest people honest, just about like anything I do on the bike security-wise.




The motor from the new vacuum is definitely unusable in it's current state--one of the bearing cups on the shaft has ruptured, and spilled shorn bearings and bits of the cup into the motor. Doesn't appear to have damaged anything other than the bearings themselves, and the cups to hold them, but it means the mechanics of this motor need repair before I can use it. Of course, the windings from the shunt coil can be used regardless, since I won't be using that part as a motor anyway (all these motors will be rebuilt to use permanent magnets instead, even if I leave their armatures and rotor windings intact). So, another few dozen feet of wire, and a potential motor once repaired and "upgraded". The cords from both vacuums could make good wire for the bike, since it includes the outer covering, and is fairly heavy wire, stranded instead of solid, and might be suitable for battery-to-controller and controller-to-motor connections, and be weather- and abrasion-resistant.

Most of the rest of the vacuums are not really useful for the bike right now, but since I never can tell what inspiration will hit me or when, I'll save all the parts in my "other" bin. :-)

That's it for now.

Tercel Motor Video

First up, as promised, some video of the motor in operation. Pretty boring, but you can see it as it speeds the wheel up and slows down from throttle control. The entire drivetrain, excluding controller, is in view. Can't see the keyswitch, throttle and battery meter, though, as that's on the handlebars. I don't have time right now to edit together a pic-in-pic of the throttle controlling the system, which is what I'd like to do, with audio commentary that makes sense.


video

More pics of the bike to come later (no room on it for stills with the video recording, as I only have the built-in memory, and no MemoryStick (ProDuo) for it yet.

Wednesday, January 16, 2008

Car parts turned traitor, again.

Today I tested the Toyota Tercel engine fan motor I'd gotten from a friend's scrapped car. I did not expect it to be very powerful, but turns out that it has actually got some decent power to it, even at only 12v--it draws about 4amps at 12v with just the plastic fan as a load, and only about 400ma with no load on shaft at all. Of course, it's designed to run really fast, rather than give a lot of torque, but gear reduction will fix that. The fan motor is a nearly-sealed motor, with just a drainage tube at the bottom allowing inside access, so it's essentially weatherproof--ideal for the bike project.

I did the testing on the same bike I tested the scooter motor on, my spare "experimental" bike, the Kensington that doesn't have a fluorescent paint job. No pics yet, as I am still recharging the camera's battery (I forgot to do so after the last bunch of pics and video, and it had been sitting for a while before that, too). That's the bike that has the large scooter's sprocket bolted and JBWelded to it's rear wheel, on the left side (because I can't remove the freewheel for it from the scooter's wheel).

Coincidentally, the flatted shaft the fan motor has almost perfectly fits the scooter motor's small sprocket (a little loose, but not enough to worry me for testing purposes), so I tested it with a hacked-together mount in place of the dying scooter motor, and it will spin the bike tire (with bike upside down) at a fantastic speed, enough to shake the entire bike badly from the tire's circumferential imbalances (it has Slime in the tube, and the tire itself isn't perfectly round). Once I load it down by actually riding the bike, it doesn't give enough power to start moving the bike by itself, but it does add some speed to it if I first get up to speed by pedalling. I need to test using the bike computer/PDA to see what the difference in acceleration and speed are with and without the motor, though, as well as the actual speeds I'm going (guessing about 15mph).

Under load, at 24v, using my repaired scooter speed controller (which requires 14v minimum to even start), it draws about 10 amps max at ramp-up to speed, and about 4 amps steady at 1/2 speed. I can't run it at full speed, because that would spin the motor shaft so fast it will cause the chain to jump off of it's sprocket (it does get a lot of torque at it's top speed). The gear reduction is being done by a very large sprocket at the wheel end:

and a very small sprocket at the motor end:

It's not enough, for this motor. I need a second reduction step, probably for any car fan motor I use. The only way I can do this at this moment is to take the small sprocket and put it on an idler shaft along with another large sprocket, and then another small sprocket on the motor shaft. Chain runs from motor to large sprocket on idler, and a separate chain from small sprocket on idler to large sprocket on bike wheel. That would be enough reduction to give me torque at a low enough speed to be useful on the road, without the chains jumping ship every time I throttle up. :)

Oh, and the magnet-in-glove trick to control a hall sensor on the handlebar for a throttle works great. :) I just mime the motion of turning a throttle like on a motorcycle, and the motor revs right up. Only problem is that I need a biasing magnet to keep the Hall sensor outputting 0V when no glove magnet is near it, because otherwise it outputs 1/2 of it's nominal throttle control voltage, making the system start at 1/2 speed with no rider on it. :-(

I used the entire controller system, including headlight, battery meter, and keyed "ignition" switch from the scooter for this test, just zip-tied to the bike in appropriate places for now, since it'll be coming on and off the bike a lot for modifications as I continue all this testing.

Tuesday, January 15, 2008

Hmm..... Is the audience really listening?

Well, it appears there are *some* people reading this blog, but at least one of them is not reading it very carefully, or else doesn't understand what I've said in various places in it.

The first comment on the last post I made was this:
"Anonymous said...

Gee, why don't you just buy a Cryalyte motor for $250 and be done with it?

January 15, 2008 6:24 AM"

My response was this:
"Well, I suppose that Anonymous here that posted this comment hasn't
actually read much of this blog, if any of it. Especially the parts that talk
about not buying anything for it wherever possible due to lack of money
and the goal of trying to use 100% recycled components. :-P"

Even if I had the money to buy a motor outright, part of the point of this project is to not buy off-the-shelf parts, but to build it from recycled parts whereever possible. If I could find someone throwing out such a motor, I'd gladly try to integrate it into one of the bike versions, but there's no way I could buy something that expensive.

If I had that kind of money, I'd be buying proper tools for this project first, and good bike parts, etc., to make a safer bike first. It's part of why I haven't got the good safety fluorescent paintjob on the bike and my riding gear yet, and why I don't have good safety riding gear, just used stuff from a thrift store, etc. Also why I don't have the turn signals and marker lights built yet--I simply don't have enough high-brightness LED's to make effective signals unless it's really dark, so hand-signals are still safer to use at this point for most of my riding, even though many drivers (and pedestrians and other bikers!) apparently have no idea what these mean.

But money aside, one definite goal of this project is to use recycled parts wherever possible. And it is also fun to take things apart and put them back together into other things in ways they were never imagined to be by their designers, and have it actually all function because of work I did with my own hands.

One other issue with using well-known components like Crystalyte motors is that they're easily recognizable, and while I could disguise it, on their own they make bikes more of a target for thieves, because they know they can easily resell these well-known components for quick money. Something hacked together like what I am doing doesn't have a lot of resale value, and in general is pretty ugly, and hopefully not as attractive to thieves. It really sucks to come out of a store or job several miles or more from your home to find that your only transportation is now missing. (Not to mention all the hard work put into it, and any money spent on it). If a bike is stolen, it's pretty much guaranteed you'll never see it again--it's not worth enough for the police to give a damn about, since they've got cars worth way more than that being stolen all over the place as well that they have to try to find first, and even most of those will probably never be found.

I also am trying to avoid putting Chinese crap on my bike, or using it at all in my life where possible (it's really really hard to avoid, though). When I do have to buy new stuff, I am trying to find stuff made here in the USA, because it means that somewhere here there's one more job kept alive a little longer. I've been out of work myself before due to companies "downsizing" because of "exported jobs", and currently am having trouble finding a job to pay well enough to keep me in rent/etc, so I know how bad it can be when you have a job taken away because the company you work for can't sell enough of whatever they do to keep you around, due to overseas "slave labor" like China has. It makes a difference for me to buy "local", even though very very little, but it does make that difference. If all of us did that, perhaps the economy would be in better shape, and fewer skilled people would be looking for work so they don't have to lose everything they built up in their life.

Of magnets, wire, and gears

I have done a bit more work on converting the cieling fan motor into the hub motor, mostly figuring out what calculations I have to worry about, and researching magnets and whatnot that I'll have to buy someday to finish it. Unfortunately there's nothing I can find to take apart that has the magnets I need in it, which have to be the rare earth Neodymium types, and of the type that are polarized thru their thickness, so the north or south pole of each one faces away or toward the windings/motor axis. I can get them as cheap as a buck each, but I need at least 12, and preferably 36 of them, plus whatever shipping costs (typically $5 or $10 if they can be shipped ground, but way more if they have to go by air due to extra shielding needed by law).

The harddisk magnets I have now are nice and powerful, but totally wrong polarization and shape. I *can* still use them for a motor, if I can get enough identical ones (so far I have no more than 4 of any one kind), but it is a very different design of motor, with the windings still in a radial pattern on the fixed portion, and magnets still on the rotor outside that, but in a different configuration. The windings would be done in the plane of rotation, instead of perpendicular to it, arranged rather as an orange cut equatorially looks, with each orange interior segment representing a separate winding. The magnets, instead of running around the outer circumference, outside the radius of the windings, would be placed in the circle to either side of the windings, and have to be on *both* sides, needing twice as many magnets as the other design. Since they would then be segments of a flat arc, though, with poles along that arc, the harddisk magnets would be ideally polarized already for such a design.

The catch there is that I would have to machine a rotor for each side to mount the magnets on, and also a support plate for the windings, along with core laminations for each segment, all of which must be precisely machined and well-balanced. I have no tools to do this, and would first have to build a lathe and a drill press, and then a balancer for measuring and correcting the imbalances in each part, so the motor wouldn't shake itself (or the bike) apart as it spins.

It also is not in theory as efficient as the other design, but the ones I have seen use no iron cores in the windings, and that severely limits the field strength of the windings, compared to the other design, making for less torque (though possibly higher speed because of less cogging caused by magnetic attraction to the cores from the rotor magnets). With a core in each winding, it would improve the torque a lot, but also increase cogging, probably dramatically since there will be opposing magnets on each side of it.

Right now, I can't build *either* motor, because I either need to buy magnets, or I need to machine precision parts with tools I don't yet have. So I'm again looking into alternative existing motors.

A friend is going to haul a Toyota Tercel to the junkyard soon, so he is letting me part out whatever I want off of it first. I already got the small fan motor it has, which is a highspeed low-torque motor, which if I can build a reduction gear set for it (it's too big a speed difference to do it with chain and sprocket--even if it didn't break something it'd be VERY noisy and dangerous to leave exposed to potential chain contact with anything) might actually be able to drive the bike a little, though not as much as I need, I think. One really nice thing about it is that it's a sealed motor, so it's essentially weatherproof--ideal for the bike for that reason, at least.

I also got the car battery, which while old does hold a charge. Even after only a couple hours of charging it would run one of my higher-torque motors well enough that I could not hold the spindle stalled with pliers after power was applied, so it will be useful for testing stuff "in the lab" so to speak. It's too heavy to use for actual bike power, of course (I think it weighs more than the whole bike; I can barely lift and carry it). I'd like to get the alternator and starter off, too, since they have wire on them I can use to rewind onto other motors, but I would have to jack the car up to do it, since they're *under* the engine and behind it, since it's a transverse-mounted engine. I'd also love to take out as much of the engine compartment wiring harnesses as possible, since they have "weatherproof" connectors on them, but I didn't have time to do that, and might not before it is hauled off.

I also have a vacuum-cleaner motor, from a Dirt Devil that was donated to me since it has broken plastics on it. Motor works fine, and since it's a shunt motor, it will even run fine on DC (battery) power, even though it's from an AC-powered vacuum. It just takes a lot more power than a motor with permanent magnets in it would to do the same work, since the "magnets" are being created by the shunts using lots of extra battery power, in addition to that in the regular windings. Again, it's a highspeed, low-torque motor, and not nearly as suitable as the fan motor would be, either, since it's an open-cage motor.

The problem with these highspeed motors is that I must build a reduction gear set for them, and I really have no easy source of tough gears--just plastic ones from laser printers and the like, and even there, most of them won't mesh with each other in the ways I need them to for the right ratios.

Again, I'm stuck with having to precision-machine parts (gears, in this case, even harder than the other stuff), or go buy some from somewhere. I'd love to take the transmission of the Tercel apart, but I know I don't have the kind of time it would take before it's gone, and I also couldn't lift the engine out to do that. I *might* be able to get the differential apart, if it has one, but I think this is a front-wheel-drive, and I've never taken one apart to see what kind of gearing it has in it. I don't even think the rear differentials have the gearing I need, so probably front ones won't either. I really need to get a pile of tough gears of many ratios that all have the same tooth size, so I can use any pair of them together for various motor experiments. Just haven't found a good source yet that is as close to free as possible--most want more than ten bucks *per gear*, which is ridiculous for used parts rusting away in a junkyard. :(

Ah, well, I'm learning a lot, and it's fun, if a bit frustrating due to insufficient resources for experimentation. It's actually made me more thoughtful and inventive in my scavenging, as I am finding parts sources for things I would not have imagined before. For instance, TV's have a lot of loosely wound copper magnet wire in them, on the yoke of the CRT. Old CRT PC monitors, too. The bigger the tube, the more wire (and sometimes thicker, too). Most AC motors are loosely wound, and easy to get apart. Tranformers are often also this way, and big ones are found in many large UPS's, though there aren't many turns of wire on them, apparently, from what I'm finding. Thick, though. (one of the Tripplites I took apart has a transformer with magnet wire more than 1/8" thick, and square in cross-section, stiff enough I could make bracelets out of it!).

I also will have some more bikes to experiment upon tomorrow, as I finally got first dibs on something from the Freecycle mailing list (after a bit less than a couple months of trying). Unfortunately someone else I was to go get some old (but working) celphones from tomorrow morning already gave them away to someone else, after telling me I could come get them. At least she did let me know they were gone tonite, rather than letting me go tomorrow and find them gone when I got there. Can't complain much, though, since it's all free stuff someone else is giving away because they don't need it anymore. :)

The irony of much of the Freecycle stuff is that if I had a working motor on the bike, I'd have the range and speed I need to get more motors--there's been a number of people on outlying areas that have had things I could use to finish a bike with, but I would need a finished bike to go get them, unless I feel like pedalling out there for 5 or 6 hours, and then the same back again. I'd have to leave in the dark in the morning, and come back in the dark at night. :(

However, perseverance and patience are my friends, so I will get what I need eventually. :)

Sunday, January 6, 2008

PDA's, cable boxes, and leftover motherboard junk.....

I got the bike computer working, finally. Since it's built from an old PDA that's been in a box of "dead stuff" for years, and I'd never tried to use it, I wasn't sure it would even work at all. I'd tried to do it with a Sony Clie, but it kept crashing during use, and when that happened, I'd have to reload the whole PDA from the PC, since it requires disconnecting the battery to fix it (which loses everything in it); reset doesn't work--that means the Clie can't be used unless I can figure out why it crashes and fix it (probably hardware defect, and probably not fixable by me).

So I dug thru my boxes of collected junk and found a Handspring Treo (black & white screen) that was revivable. I had to take it's totally dead Li-Ion battery out and put the one from the Sony in it (doesn't fit well--too tight), and swap connectors. Also, since I don't have the charger cable for it, I had to solder a connector from a PDA with a broken screen to the charging wires on the battery and run that outside the case, using an old Nokia charger that's rated 3.7v (but is only that under load, as the load drops it gets too high a voltage, and I'll have to regulate it before I can leave it on the charger unattended).

Unfortunately the Treo's celphone RF seems to have something wrong with it that even when I turn that off it still uses a LOT of power, as it stays very warm in the whole shielded area on the board where that stuff is at. There's no way I can see of disconnecting those circuits without keeping the rest of the PDA portion from working; I may try just removing the primary TX/RX analog power output section if I can, and see if that causes the chipset to become inactive (I doubt it will work). The power usage means a fully charged battery that on the Clie lasts for several days before I have to recharge it won't even last 45 minutes *in standby* on the Treo, and max of 20 minutes active usage--barely enough time to get to work from home, and I can't test it the reverse path, because by the time I get done working, it's long dead. Fortunately it does keep enough charge when totally inactive to hold memory, so I don't have to resync it every time it dies, but there's no way I can use it as a bike computer until I fix this. Not exactly square one, but it's a definite setback, with two PDAs I can *almost* use. At least there's hope for the Treo, and not a lot for the Clie. The Treo has the advantage of the flip cover, which protects the screen against random things hitting it during a ride, but lets me still see the display.

The mounting of the Treo is just a right-angle piece of aluminum I bolted to the headlight mount, and a piece of foam glued there to hold it at an angle I can easily see while riding. The Treo's antenna unscrews, and since I don't care about the phone part of it, I just unscrew that and thread it back in thru a hole in the bracket, which holds the Treo in place pretty well. I'll make a better bracket eventually, but this is a quick-release mount that lets me take the Treo off the bike when I have to leave it so thieves don't steal it, or jerks break it just cuz they can. (People do sometimes just break stuff on my bike, not like they were trying to steal it, but like they were just feeling vandalistic that day. I wish I could electrify the whole thing with a non-lethal voltage to teach them a lesson. Only non-lethal cuz I wouldn't want someone accidentally dying because they brushed up against it as they pass the bike rack. But I can't, because that's against the boobytrapping laws here).

Since I wanted to mount the PDA horizontally, using the antenna-screwpoint as the mount for now (it'll never be a celphone for me anyway), I used the Fliphack by Douglas I. Anderson, referenced on the VeloAce page by Mark Hämmerling, to turn the display 90 degrees to make it possible to read it while it's sideways. Only thing I don't like is that every time I have to reset the PDA (a lot right now), I have to tell Fliphack to rotate back to 90 again. Probably won't have to worry once I fix the power-consumption problem.

One issue with the current mounting method is that it is very hard with gloved fingers to reach the power button, which is the only place I can turn the backlight on with, using a doubleclick of it. Almost always, I only get one of the two clicks, so it just puts the PDA in standby instead of turning on the backlight (necessary during night rides). If I permanently use the Treo as the bike computer, I'll make a new big momentary-contact button with a bit of logic to do the doubleclick for me, mounted in the flipcover, to make it easy to toggle the backlight while riding, under any conditions. The flipcover also has a switch in it that when opened will turn on a specific program--it's set by the Treo as the phonebook, and there's no built-in provision to change it, but I read of a control panel hack called ButtonsT that lets you reassign both that and the wheelclick button to anything you want.

Dunno what I will change it to, but probably another free program called Dinky Pad by Edward Keyes, so I can quickly jot something down during a ride without dealing with paper/pen or the Palm's Graffiti system or teeny-tiny keyboard. Just flip open the lid and write with whatever pointy thing I have in hand (preferably the stylus, but even a finger will work for some things)--handy for noting down the license plate of any vehicle that tries to run me over or does something else stupid and illegal that could get someone killed or hurt, or even just writing down that other thing I wanted to get at the grocery store before I forget *again*.

The IR transmitter LED is glued to the inward face of the righthand brake handlebar mount, because that directly faces the sensor-end of the PDA. It's barely visible in the pics, because it is almost black, against the black plastic of the brake mount.

The actual wheel-revolution counter circuit is built from parts off of various dead motherboards, plus a magnetic reed switch out of a very old (and large) calculator keypad. I used a couple little round magnets off an old CompUSA namebadge to glue to the wheel spokes, so the switch is engaged once per wheel-turn. An old project-box about the size of a deck of cards is zip-tied and siliconed to the fork, and contains the jacks and battery and circuit (with room left for two or three more of the same). Eventually I think I'll move the entire electronics to the handlebars, along with any other front-end electronics I add, into a custom-made metal "console" that can survive crashes and direct sunlight better than plastic.

The free VeloAce program can use IR input from the wheel sensor to count revolutions, so I took an old cable-tv-box IR transmitter (supposed to be used to tell your VCR to record by faking it's remote control, you just tape it up next to the remote input face on the front of the VCR) and running that from the wheel up to the area near the mounting for the "computer", so it will be able to send the IR signal to it (the signal is just a specific-duration blink of the IR LED every time the wheel turns). Since it had a handy headphone-sized plug on the IR unit already, I just put a jack off a dead motherboard into the electronics box for the sensors to plug that into.

It's a 3-port jack-stack, so once I find my box of dead headphones, I'll put jacks on both the front and rear wheel-sensors, so I can unplug one or the other for testing if needed. Normally only one sensor is needed, but since I want to do RPM tests of the motor-driven wheel, whichever one that is at the time, I put sensors on both wheels. Only one can be used at a time, so for now I don't have the magnet on the rear wheel glued in place, it just sticks to the spoke-end by magnetism when testing with it in-house (not safe for road conditions, because vibration would probably knock it off quickly). The in-house tests aren't done with the wheel on the ground, so the only vibration is from misalignment and chain-drive, both of which are minimal.


I also did some modifications to the headlight while I was working out a mount for the Treo: I removed the old wallmount cieling-fan-control, since I was only using one switch in it anyway, and put the switch in the top of the headlight. All the wires now run into the back of the headlight thru holes I'd already had drilled into it for a previous mounting I no longer use, and had siliconed shut--I just poked them thru the silicone, so they have a decent rain seal already. It all still is wired the same and does the same things, it's just neater and less stuff on my handlebars, making room for things like the PDA. The images here show it as it's assembled (the electronics board in there is just the inverter for the cold-cathode fluorescent of the headlight, which is all what was in this HP scanner-film-slide-negative assembly originally).

I'd like to replace the CCF with LED's, to drop the power consumption by about 90%, but haven't got enough white or near-white ones that are bright enough in total to give the same light output. I consider the CCF itself to be barely bright enough, and it's pretty dang bright. I'd prefer something that gives off *at least* as much light as a high-brightness automotive headlamp, and preferably twice that, with as much surface area as the existing headlight assembly I have now, but *all* light-emitting, instead of the maybe 40% light-emitting it is now. I want to *be seen*. The light is not really for my own benefit, since I generally have enough streetlamp lighting to see by, but rather it's for oncoming (and other) traffic to see *me*, so I don't get into bad situations both in the dark and in non-optimum daylight conditions.

You might be surprised how quickly a bicycle and rider, even with fluorescent colors all over them, can disappear from a driver's view when passing into the shade from overhanging trees and buildings and whatnot, on a bright enough day. I didn't think it would be possible to *not* see me with the paint job on that bike, and my "Dayglo Avenger" riding gear, but I still seem to have some not-really-paying-attention drivers either honk, swerve, or screech their brakes when they suddenly notice me in the bike lane when riding in areas (such as around Metrocenter) that have lots of shady/bright areas. They have no reason to react the way they do, since I'm in a separately-marked bike lane, out of their traffic lane, and not blocking their path at all, and I'm riding slowly and steadily in a straight path (or curved if following a curved road, but still in the middle of the bike lane, predictable as I can possibly be). I'm certainly not stealthy, nor unpredictable or sudden in my moves, and I look and signal before making any changes in lanes or turning. Sometimes I cannot signal when I stop, but that is why I made my taillight also a brake light, just like a car/truck/etc.

Ah, well, they might react the same to suddenly noticing a car driving alongside them that has been there all along, in a different set of traffic conditions, for all I know. I'd be happy as long as they *do* see me, and keep me in mind when driving near me, not suddenly cutting me off by gunning their engines and making a right turn in front of me where I can't stop in time (still all too common, when all they would have to do is not gun their engine and they'd be able to make their turn safely in the few seconds it would take me to pass the intersection and be out of their way completely and safely).

Someday, perhaps.