Motorcycles are hard to see at the best of times, so riders are often concerned with making themselves as visible as possible at all times. [Josh] wanted to do this by creating a custom tail light for his Ducati 749.
The tail light is based around SMD LEDs, mounted in acrylic to diffuse the light. The construction is beautiful, using custom PCBs and carefully machined acrylic to match the lines of the bike.
As far as warning lights go, a brighter light will be more obvious in the day time, but could actually hinder visibility at night by blinding other road users. To this end, [Josh] built the tail light around an ATtiny 45, which could be programmed with various routines to optimise the light level depending on ambient conditions. Another feature is that the light’s brightness pulses at high frequency in an attempt to attract the eye. Many automakers have experimented with similar systems. The ATtiny controls the lights through a PCA9952 LED controller over I2C. This chip has plenty of channels for controlling a bunch of LEDs at once, making the job easy.
Overall, it’s a very tidy build that lends a very futuristic edge to the bike. We’ve seen [Josh]’s work in this space before, too – with this awesome instrument display on a Suzuki GSX-R.
Not sure now, but some time ago blinking lights were considered illegal in the USA. But some automakers still used them with no apparent legal difficulties.
Well, blinking lights for emergency braking do make sense. For me it’s a sign that something’s really off and that i should proceed with high caution.
Restricted in this state. Exception to the law was added to allow on Govt Owned Emergency Vehicles Only… BECAUSE THEY WORK!
I’d completely understand prohibiting constantly blinking ones, because that would be annoying as hell.
But i don’t see why they shouldn’t be allowed during really hard braking.
I know. They improve safety a great deal… yet…
There are many privately owned ambulance services, but they may not use them either.
Also, tinted windows are not allowed on vehicles here either, but the State Police have a whole fleet of unmarked SUV’s with all the windows deep black, as the do all the sedans for legislators. But whoa if YOU have them! = Ticket. Even tinted visors on a motorcycle helmet fall under the same law! Sunglasses are fine though? ????
Just as inexplicable as the watermelon seed spitting contest, the (ewww) cow-chip throwing contest, cheese-head hats, the Polar Bear Club cutting holes in the ice for a New Year’s swim, and McCarthyism.
I apologize! Promise!
I suspect those annoying blinking brake lights were installed by a dealer to get some extra profit on the car – I’m not aware of anything like that being factory installed.
There is some confusion in blinking lights and a high frequency modulation that makes the light brighter than if not. Most LED lights other than headlights seem to “vibrate” if seen with an averted glance. The link is for brake lights that briefly strobe then go steady when hit harder than light.
They seem to vibrate because of the PWM used to drive them
And, very few companies understand how high that frequency really needs to be. General motors is the worst.
My wife and I both feel instant nausea when we see the tail lights of an Escalade or certain Cadillac sedans.
Brake lights do not cause nausea, grandpa. Jesus, get over yourself. You sound like one of those loons that complained that CFLs gave them headaches. You THINK the light is making you sick.
Ditto the flicker complaint!
Getting caught in heavy traffic has become a serious Migraine hazard now.
echodelta mentioned the glance factor. That gets really bad when you’re having to constantly scan the vehicles, around you, in about 5 lanes.
I’ve actually had to shift my shopping/driving times to (“3rd shift type hrs”) avoid the headache triggers.
It would be nice to see a bit of a slope in the switching vs just banging a “square” waveform into the LEDs.
Could some sort of simple capacitor~inductor~resister combo be used to give a non-square waveform??
a few of us would Really be grateful!
Same, I hate the flicker…
And it is probably some lame reason…
Like using an Arduino DigitalWrite, instead of the actual PWM peripheral on the microcontroller. ;P
It’s probably because they’ve gone for the cheapest automotive grade hardware they can find. Probably something without a hardware PWM.
Yeah, that is probably true…
They do the same for the infotainment processor:
“What is the cheapest processor we can get?”
Then later…
“750ms lag from press to GUI update is not THAT bad” ;)
Motorcycle headlights often seem to vibrate, because they are! B^)
One used to be able to buy a device for your motorcycle that would flash the High Beam while keeping the Low Beam on to make the motorcycle more visible to oncoming traffic, hopefully reducing the possibility of oncoming drivers making a turn into the path of the motorcycle.
Concealed carry laws pretty much put an end to modulated headlights. They’re maddening!
“Motorcycles are hard to see at the best of times, so riders are often concerned with making themselves as visible as possible at all times.”
Bright colored safety vest. ;-)
Or burning-man style LED-augmented clothing :D
There were a few examples of EL tried… Looked really kewl! Then it rained.
That’s immediately what I thought as well. I saw a really good example of that a few days ago: I was driving down an road that is not illuminated, came around a corner and saw the reflective stripes of a high visibility jacket above a fairly indistinct little red light. It immediately made it easier to judge my distance from the motorbike and the bike’s speed. Making it easier for other drivers to make these judgements is what it’s all about, I wanted to thank that particular motorcyclist.
A motorcycle manual I read once, stated: Drive as if you are invisible, because to most other drivers, you are!
Vw golf V PWMs the tail lights to provide the different brightness between parking lights and brake lights
A lot of cars do that these days, often at a slow enough rate to cause a dangerous distraction and/or nausea in some people.
No, they don’t cause goddamn nausea. Find me PEER REVIEWED research or stop making things up.
Or, a random commentator such as I claim that it does in fact make me feel sick.
Forget peer reviews for something as simple as this. Blinking lights actually do affect a great majority of the population.
I do like the “dogbone” pattern of the PCB copper!
Hope the circuit is vibration resistant. I made my led tail light from led strips potted into in a machined alloy housing to keep it simple and give better vibration resistance and there was always one of the leds not working properly after a few miles of rough roads. One bad random led = annoyance, complete bad circuit taking tail light out = bad. I had to coat the pcb of my megasquirt v1 in conformal before prolonged use for the same reasons.
Another bike I have used to have its tail light bulbs fall out the bulb holders and be floating loose around the bottom of the lenses after a spirited ride, crap oem CEV light units, but shows manufacturers (bimota in this case) don’t get it right every time too. Italian motorcycle electrics of the 90’s and earlier were pretty dire though I hear the modern stuff is a lot better.
Those tail light bulbs falling out are cured by FILLING the bulb socket with dielectric grease, or the even thicker silicone vacuum grease, then inserting bulb. Also greatly reduces filament failures from bulb vibrations.
Q: Why was an ATtiny used instead of a Raspberry Pi 3?
A; The ATtiny has enough capability to do this job.
I love all the led s ,I have them all over my bike and even get a lot of compliments and also I be seen and witnessed many tragic motorcycle accidents and deaths and the answers are always the same .I Didn’t see him or her ….
I assume people are aware that PWM is used to drive LEDs at a much higher peak current (And therefore brightness ) than is possible at full duty cycle, rather than to just piss other people off?
I.e. we use a bunch of LEDs for machine vision lighting (LED strobe linked to camera shutter at 120fps), spec sheet says around 0.5A continuous, we run around 6A strobed and to the naked eye, it’s a LOT brighter than the equivalent 100%DC at same average watts.
Reference all videos of any new car LED head/tail lights, frame rate trickery shows light pulses.
LED tail light is a good light to improve the motorcycle visibility. If you want to improve your motorcycle visibility click this link and see the entire configuration and buy it at reasonable price. It will definitely improve the visibility.