Wireless signal needed from motorcycle to backpack - don't know how

[Luegolover]

Hello,

I am not sure if you provide this type of advice but I am interested in creating a rucksack for my motorcycle that has LED lights that operate the lights/brake lights/indicators when they are used and I don’t know how to do it. I can get the 12V signals from the motorcycle and I have the LED lights, also 12V for the bag and I can do simple electronic soldering. What I need is a transmitter & receiver that can relay the 4 separate signals from the bike to the bag. I was hoping that I can make a simple and physically small device to do this but I don’t know how. Is this something you could help me with or do you know who could? There is a company who makes such a bag but they are very expensive and I would greatly enjoy doing it myself so I would prefer to go my own way. The company that makes the bag is VATA7.com and this is what I would like to end up with.

If you could help me I would be grateful.

Regards
Steve

 

[Alec_t]

Welcome to EP!
Something like this might be a starting point. You would have to hack the remote to link it to your signals.

 

[Luegolover]

Thanks,

Would that be as simple as ripping the remote apart and linking the individual 12V signal wires to the relevant push button outputs?

 

[Alec_t]

It might be that simple, if the remote operates from 12V and the push buttons merely apply 12V to circuit nodes. However, life is rarely that simple, so you would more likely need some interfacing circuitry, which would require reverse-engineering the remote.

 

[Bluejets]

Hello,

I am not sure if you provide this type of advice but I am interested in creating a rucksack for my motorcycle that has LED lights that operate the lights/brake lights/indicators when they are used and I don’t know how to do it. I can get the 12V signals from the motorcycle and I have the LED lights, also 12V for the bag and I can do simple electronic soldering. What I need is a transmitter & receiver that can relay the 4 separate signals from the bike to the bag. I was hoping that I can make a simple and physically small device to do this but I don’t know how. Is this something you could help me with or do you know who could? There is a company who makes such a bag but they are very expensive and I would greatly enjoy doing it myself so I would prefer to go my own way. The company that makes the bag is VATA7.com and this is what I would like to end up with.

If you could help me I would be grateful.

Regards
Steve

If you are in to Arduino it would be a relatively straight forward arrangement BUT if you need to start from scratch, not so.

 

[Luegolover]

Had to Google to discover what Arduino is, it would be from scratch.

 

[Luegolover]

I found these 433MHz RF transmitters but they operate at 5V. Is there a simple way to get a 12V signal, step it down to 5V at the bike end and the step it back up at the bag end?

https://www.ebay.co.uk/itm/433-Mhz-...e=STRK:MEBIDX:IT&_trksid=p2060353.m1438.l2649

Would these things do the job?

 

[Bluejets]

You could but you'll need Arduino or similar microcontroller to load and manage the data and control the Tx and Rx.
Best you stick with something like Alec_t suggested and get a helping hand from a friend with some electronics knowledge.
Otherwise you will get nowhere fast.

 

[Tha fios agaibh]

Or, go old technology and use a "coil cord" and plug in your backpack.

Yes it'd be more cumbersome, but with the added advantage of not needing to keep a battery inside your backpack.

 

[Luegolover]

I've ordered the suggested wireless remote and will see if I can modify the key fob.

The coil cord solution has merit but I'm such a forgetful dimwit that I would forget I had it plugged in and up walking off whilst connected.

Thanks for the help so far and I've no doubt that I'll be back in touch with questions once I have the device.

 

[Tha fios agaibh]

I would investigate how the remote works.
I believe the 4 channels work independently so you wouldn't be able to control two signals at once such as the brake light and turn signal. It's likely that only one remote control button can be pushed at a time.

 

[Luegolover]

OK, that does sound plausible which would make it unsuitable as I would need the main lights and the brakes lights at the same time. I'll have a play when it arrives.

If I got a starter kit for Arduino and tinkered for a few evenings a week has anybody got any views on how long it would take to get to the stage where I could design and build a suitable controller the 433MHz transmitters/receivers? I am not in a great rush for this and I could plug away for a few hours a week if needed. I once built a MegaSquirt CPU for a kit car I was making and the car ran well. It took me many months and I had an instruction manual which was a tad too complicated for me but I got there so I could probably get there again. I guess I'm asking for a idea on how feasible it is to go the Arduino route?

 

[Bluejets]

I would investigate how the remote works.
I believe the 4 channels work independently so you wouldn't be able to control two signals at once such as the brake light and turn signal. It's likely that only one remote control button can be pushed at a time.

It is possible to set the buttons to "toggle".( latch)

As far as how feasible it is to go Arduino, well, that was why I originally suggested it. It's just one of the mass of "feasible" operations the Arduino can handle.
The question would be how dedicated you are to learning how to use it. The Arduino forum will "help" you but you must do for yourself. No one is going to write the code for you.
It is possible there is already something similar out there already however you'll need to search for it.

 

[Luegolover]

I've been thinking on this and well, my world is like this; Day job: teacher, weekend hobbies: restoring a 1954 car / riding motorcycle / watching football. This does leave me with free evenings which I have generally used for surfing as I am too whacked out to do much more but I could sit and tinker with a starter kit and see how it goes.

Arduino sell the starter kit for €80 plus tax but eBay has some listed at £27. Is the eBay kit ok to start with or will I forever regret getting the cheap copy?

 

[Tha fios agaibh]

It is possible to set the buttons to "toggle".

Thats fine but like I said, I don't believe the signals can operate simultaneously like would be needed here.

I don't get the microcontroller idea.
Wouldn't you need 3 transmit/receive signals anyway, even if you were to use Aurduino? Or is it a multiplexed signal?

 

[hevans1944]

Firstly, you need a PLAN before committing to building anything. It would be a good idea to start off with a BLOCK DIAGRAM that abstractly represents what you are trying to DO. The block diagram can start out as a simple box outline with various gazintas (inputs) and gazoutas (outputs). Each of these needs to be precisely defined. You also need to define what occurs for ANY combination of gazintas along with the possible influence, if any, of the gazoutas on the gazintas. The latter situation is used to implement a state machine, which may or may not be necessary to "light up" your motorcycle backpack.

Secondly, if you decide to implement with an Arduino the logic contained in the block diagram you created, you need to spend a few weeks becoming familiar with the Arduino architecture, the types of inputs and the types of outputs available, and rudiments of the C# programming language from which programs (called sketches in Arduino-speak) are created on a personal computer, compiled (translated into machine language), and then downloaded to non-volatile memory for execution on the Arduino. This program development environment is free and is easily downloaded to your PC through an Internet connection.

The Arduino has a red LED connected to one of its output port bits. Beginners usually write simple sketches to control this LED, turning it on or off by means of switches connected to input port bits, controlling the LED intensity by varying the duty-cycle of pulses applied to its output port (pulse-width modulation or PWM), controlling the PWM output by reading and digitizing an analog input signal, usually derived from a simple potentiometer connected between the +5 VDC supply and COMMON, the pot wiper signal being applied as an analog input to an Arduino input port configured with an analog-to-digital converter that is part of the Arduino architecture. All this will probably take as much as forty hours of your time to climb the learning curve. Less, if you have any experience with microprocessor hardware.

Thirdly, the RF transmitter and receiver are designed to transmit and receive a serial digital data stream. That means you are responsible for writing an Arduino sketch that will implement a suitable protocol. Serial ASCII (Google this) is the usual first choice, with or without parity checking and with or without cyclic redundancy checks. You may want to add "bells and whistles" such as error detection and correction by organizing the data transmission in packets, with packets containing uncorrectable errors being re-transmitted on request of the receiver. Or not. Depends on the consequences if data is corrupted and the sketch continues as if nothing inappropriate has happened. You decide.

Finally, string all this together and add power electronics to interface LEDs to the Arduino output ports. Provide signal conditioning, perhaps, for switch inputs from brakes, turn signals, high-low headlight beams and whatever else is going to affect the backpack light display show. Don't worry too much right now about voltages. You can purchase DC-to-DC buck/boost converters dirt cheap from Asia to go back and forth between 5 VDC and 12 VDC power. For test and development purposes, plan on using wall-wart power supplies to provide 5 V and 12 V DC power until you are ready to "suit up" and take it for a ride. Good luck with this project!

 

[Bluejets]

Arduino sell the starter kit for €80 plus tax but eBay has some listed at £27. Is the eBay kit ok to start with or will I forever regret getting the cheap copy?

There is no real need to get any "original starter kit".
I've used clone boards for years without any problems.
A few LEDs and resistors, a clone Arduino Uno , a few tactile switches, elcheapo breadboard with jumper cables would get you started.
In fact an Ebay set here for around Aus$12.00 including delivery.

https://www.ebay.com.au/itm/UNO-R3-...c5ec917f:m:mvgmn5nt8Wmmg6cnQ1aMFIQ:rk:29:pf:0

 

[Bluejets]

Thats fine but like I said, I don't believe the signals can operate simultaneously like would be needed here.

I don't get the microcontroller idea.
Wouldn't you need 3 transmit/receive signals anyway, even if you were to use Aurduino? Or is it a multiplexed signal?

No. The signals can follow one another.
The controller operates at around 16mhz so one will never be aware of the delay between signals.

 

[Tha fios agaibh]

with various gazintas (inputs) and gazouttas

Thanks hevans1944 for that highfalutin explanation. Seriously, well put

No. The signals can follow one another.

Thanks. That's what I meant by multiplexed. Serial digital datastream of signals that are stacked together.

I not a microcontroller guy but I understand Arduino is popular. Inexpensive price and quite user friendly .
That aside, it's still a daunting task for a beginner to learn and writing C+ code.
Wouldn't it be simpler and maybe more practical, to just use three separate RF transmitter/receiver pairs to accomplish the same goal?
I see a ton of those 315 and 433Mhz transmitter/receiver pair boards online for a few $ a pair.
Presumably you could find three different frequencies and control the led lights directly (or with a few added discrete components) from the receiver boards itself rather than a microcontroller?

Just a thought.

 

[hevans1944]

There is definitely a possible, even probable, problem with two or more transmitters operating simultaneously. The problem is receiver front-end overload from nearby additional transmitters. When this happens, nothing intelligent makes it through the interference.

As an amateur radio operator, I know this can be a very serious problem during annual Field Day events when a group of Hams get together outdoors in June to try to make as many contacts as possible during a twenty-four hour period with other Hams, on as many Ham-allocated frequencies as they can erect temporary antennas, using a multiplicity of radios of various power outputs from milliwatts to kilowatts. Without some real organization it quickly becomes a fluster-cluck (think barnyard chickens who have spotted a cat in their midst) with lots of finger pointing at suspected interference offenders.

Serious operators use band-pass filters in their transmitter outputs, and/or "roofing" filters in their receiver inputs, to help eliminate the mutual interference. This is probably not very practical for a backpack scenario on a motorcycle though. Best to settle on one transmitter/receiver, operating on a single frequency, with time-division multiplexing of the digital data moving between transmitter and receiver. This protocol is relatively easy to implement using Arduino. And try to keep the power output from the transmitter very low (milliwatts) to avoid interference with other services.