Givi Maxia Tail-Stop-Turn project

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torch

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The V-56 case comes prepped for LED lighting on each side. The Givi option is real slick, with spring-loaded mating contacts that does not impact installation and removal of the trunk -- but, it's brake lights only, with only two conductors passed through the case.

02_bottom_contacts.jpg


Wires run inside a provided channel up to a second set of contacts to deliver the power to the lid:

03_inside_contacts.jpg


The LED strips get wired to the contacts at the centre rear of the lid:

05_inside_lid.jpg


Admore lighting offers a tail-turn-brake kit, but one must remember to hook up the twist-lock connector manually each time. And of course unhook it when removing the case. And the wiring has to be routed over the hinged side and across the inside of the lid. Not particularly elegant. Wouldn't it be nice if one could enjoy Givi's simplicity but with Admore's features?

Two conductors is all that is needed to get power up to the lid. What is needed is a way to control the lights remotely, without wires. As in Bluetooth. And with the capability to modulate the power to the LED strips through PWM. But tiny, so it can be tucked out of the way.

Enter the Arduino Nano 33 IOT:

06_arduino_nano_iot.jpg


Small enough to tuck into the plastic shroud surrounding the contacts in the lid. With enough room left over for a pair of IRLB8721PB mosfets to drive the LED strips. With a pair of 330 ohm dropping resistors to bleed voltage from the gates. Note that the Nano IOT is 3.3v hardware, so the mosfet has to have a very low threshold voltage. Standard mosfets need a transistor to drive the gate at that voltage level.

07_installed_in_lid.jpg


Ok, great. The lid has a receiver. No good without something to tell it what to do! First, we need access to the bike's wiring. All 5 wires are fed through a 6 position connector behind the left side panel on the GenII.

08_taillight_harness.jpg


I picked up the 6 position connectors that mate with the OEM harness from Eastern Beaver. (While I was ordering, I picked up some of the 4 position connectors too -- they will mate with the ABS connector so I can replicate the unobtanium Yamaha service tool.)

09_OEM_style_connectors.jpg


I used 2 pairs to make a Y adapter. That way I can unplug the second Nano IOT without interrupting the bike's wiring, but more importantly, there are 5 fewer wires I have to squeeze into the project box. But it would work equally well to insert the Nano inline using just one pair of connectors if the box is big enough.

10_central_and_splitter.jpg


The project box contains the second Nano. I used one of the 4 position pairs for the wires to the Givi rack, because I forgot to order a 2 terminal connector pair :oops:. That box was just about the perfect size:

12_project_box.jpg


I mounted this one on a perf board, making it neater than the "dead bug" wiring needed to squeeze things into the lid. Remember, the Nano is a 3.3v device; applying the bike's 12v system direct to the input pins would cook it. I buffered the inputs with AMS1117-3.3 based buck converter modules. Very similar to a traditional TO-220 3 terminal voltage regulator (which would also work) in size and appearance, but without the live voltage heat sink tab. (Slightly different pinout too!) Each high-impedance digital input pin on the Nano requires a 10k dropping resistor to ground as well.

11_Central.jpg


So the way the system works is the two units pair with each other using a unique 128 bit UUID to prevent interference from other Bluetooth devices. The pairing takes less than 2 seconds from turning on the key. The unit on the bike (called "Central" in BT Low Energy parlance) monitors the brake and turn signals. Several times a second, it sends a single digit code between 0 and 9 representing the current status to the unit in the lid (AKA the "Peripheral"), which decodes it to determine the pulse width applied to the respective LED strips. The default is 30% so if communication is lost, at least you have taillights. Brakes bump both up to 100%, etc.

Here's a short clip of the final results:

View attachment KVID2315.mp4
 
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Very nice - and more work than I would (or could) do.
I have my Hyperlites which give me flashing brake and yellow turn signal LEDs. They are quite visible but would draw more attention if elevated to the top case instead of either side of the license plate.
 
The Nano IOT also includes a 3-axis inertial movement sensor. I may play with that at some point to achieve a hyper-light style flashing brake light over-ride under hard braking. A full on, full off damn-the-taillights flash for maximum attention. Possibly flashing faster as the g-force rises. I won't be worrying about signals under those braking conditions anyway! But I have to do some experimenting first: this is my first Nano-based project (although I've tinkered with the Arduino Uno for years and have used inertial movement sensors in robotics applications) so the features are all still new to me. The code for the inertial braking override would reside in the peripheral (trunk) unit, but that has ample program space left so it shouldn't be an issue.
 
Oh I don't know about "easy". I made lots of mistakes in the original programming.

If anyone else decides to try this, I'll happily share the working code.
 
That is one heck of a project and nicely done. Also way beyond my capabilitieso_O. I took an easier route: I bought a "Brake Free" helmet mounted brake light. It gives me a running light, a steady brake light with engine braking or slowing with the brakes, a strobing brake light with hard braking and it also has a hazard flasher mode. https://www.brakefreetech.com/
 
I took an easier route: I bought a "Brake Free" helmet mounted brake light.
Interesting approach. Looks like it uses accelerometers / inertial movement sensors only with no communication with the bike itself? Similar to my thoughts on triggering a flashing brake light under hard braking.

Handy for those with multiple bikes. Would need the second helmet mount for any passengers though. And have to remember to charge it up each night. Can it charge while in use? EG: plug into an accessory outlet on the bike if you are on a long ride and/or forgot to charge it the night before?
 
That is one heck of a project and nicely done. Also way beyond my capabilitieso_O. I took an easier route: I bought a "Brake Free" helmet mounted brake light. It gives me a running light, a steady brake light with engine braking or slowing with the brakes, a strobing brake light with hard braking and it also has a hazard flasher mode. https://www.brakefreetech.com/
A good, simple solution if it works as advertised. It gets the brake light up where it is most visible. I have to wonder how good their algorithm might be. Too sensitive and it would be going off with head movements and normal relatively small speed variations. If insufficiently sensitive, it might not activate when it might be needed the most i.e. stop-and-go traffic. The reviews they show on their site are good (but they aren't going to show bad ones). Does it seem to work well?

I saw a cheap wireless brake/signal device on AliExpress. I don't think I would use it on a helmet but the guts of it might make a decent solution for top case lights. A little transmitter that hooks to your brake/signal system. The receiver would go to the top case and you would just need power (or batteries) to power it. An easier solution for someone (like me) who lacks talent with electronics.
Wireless helmet brake/signal
 
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There's a question that can only be answered by the fellow behind the rider ;)

Interesting youtube review here, where the reviewer set up a camera behind him and comments on what he is doing as you watch:


Not bad. I noted a few glitches, notably once on the highway when he was engine braking but the unit failed to detect it. Which I found surprising since otherwise the unit seemed quite sensitive, even activating when he walked backwards at one point. I only noticed the "emergency braking" mode kick in once, briefly, when he came to a hard stop.

The tail light mode seemed to flicker constantly, but I believe that is probably due to an interference pattern between the unit's PWM frequency and the camera's frame rate and would not be visible to the human eye.

Overall, an interesting device that seems to work reasonably well.
 
Excellent! (y)

Now for the pièce de résistance. Modify the front signal lights so that they blink "bright-off-bright-off..." instead of "bright-dim-bright-dim..." I made that change on mine to make the signal lights more visible to oncoming traffic. I'd be interested to see how you would do it.
 
Excellent! (y)

Now for the pièce de résistance. Modify the front signal lights so that they blink "bright-off-bright-off..." instead of "bright-dim-bright-dim..." I made that change on mine to make the signal lights more visible to oncoming traffic. I'd be interested to see how you would do it.
So you want to suppress the marker light function while the signal on that side is active?

The trick is to keep it off for the 1 to 2 seconds that the turn signal is dark. With an incandescent bulb (or separate LED) some sort of timer circuit, such as a 555 timer controlling a NC relay could be started each time the turn indicator bulb gets power, opening the relay contacts. Timer is reset each time the bulb starts a flash so the marker light stays off until the turn signal has been inactive for the timer duration. A 556 timer is dual 555s so could handle both sides in one chip.

I did something similar in code for the flash function of the project above. If I relied solely on the turn signal power, then it would not function when brakes were applied (ie it would alternate between turn and brake -- no effective difference. I could easily change the value between flashes to 0 to suppress the tail light function on that side while the turn signal is active. I thought about it, but having the tail remain active between flashes seemed to make it more obvious when the brake was applied.
 
Exactly. I think I used a relay, a diode and a capacitor. It's been a while. :)
 
I would guess a resistor was in the mix too. Flasher voltage charges the cap to hold the relay open and the resistor limits the current flow as the cap discharges. Would need good size cap, depending on the relay, but would work. Silicon is more energy efficient, but not the only choice.
 
A good, simple solution if it works as advertised. It gets the brake light up where it is most visible. I have to wonder how good their algorithm might be. Too sensitive and it would be going off with head movements and normal relatively small speed variations. If insufficiently sensitive, it might not activate when it might be needed the most i.e. stop-and-go traffic. The reviews they show on their site are good (but they aren't going to show bad ones). Does it seem to work well?

I saw a cheap wireless brake/signal device on AliExpress. I don't think I would use it on a helmet but the guts of it might make a decent solution for top case lights. A little transmitter that hooks to your brake/signal system. The receiver would go to the top case and you would just need power (or batteries) to power it. An easier solution for someone (like me) who lacks talent with electronics.
Wireless helmet brake/signal
Rosskean,
To answer your question: My wife followed me in her car and noted the following; in our residential area, where I ride very slowly (30 km/h) and brake very smoothly, the brakefree light does not activate. On city streets with traffic lights, it activates and is much more noticeable than the motorcycle's brake light. I am lucky enough to be a) retired and b) living in Riverview (for those of you who don't know Riverview, it is a suburb of a small city in New Brunswick, Canada), so I cannot comment on how the brakefree light activates in stop-and-go traffic.
 
I found the pics showing the parts and assembly. I made them so that I did not have to modify any of the stock wiring.

IMG_0732.jpgIMG_0733.jpgIMG_0734.jpg
 
Thanks. It's my own cobbled together design. I started out with semiconductors and such but I wanted to distill it down to minimum complexity, parts and cost.

The signal light voltage charges the cap and energizes the relay at the same time which disconnects power to the marker light. The cap holds enough charge to keep the relay energized between blinks. When the signal light is canceled, the cap bleeds off, the relay de-energizes and the marker light comes back on. I think I had all the parts laying around in my junk assortment. I just had to order the connectors and breadboard.
 
The diode is on the input to the cap?

Nice low parts count. I thought a resistor would be required to control the current drain from the cap, but I guess not. Well done.
 
BTW: where did you source the connectors? As noted above, I sourced mine from Eastern Beaver, just wondering if there are other sources.
 
I thought a resistor would be required to control the current drain from the cap
The relay coil resistance was enough to do the trick.

The diode is on the input to the cap
Correct. The cap is across the relay. The diode prevents discharging the cap back through the light filament.


I got the connectors from here: https://www.corsa-technic.com/index.php
 

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