This looks great! I'm sure you will have many board members wanting this! I'm pretty lazy so having this tell me the tire pressures is the cat in pajamas!
This looks great! I'm sure you will have many board members wanting this! I'm pretty lazy so having this tell me the tire pressures is the cat in pajamas!
John (Jay) Bettua
2014 F6b Red- sold 2016
2020 Goldwing Matte Black
Retired U.S. Air Force MSgt
Thanks John. I didn't start this project with the intent of selling them but if people like it...
From engineering point of view , this is very nobel project . In automotive business , such a conveniences are noted and practiced already . If you are so skilled and have desire to see those improvements in Goldwing's future production , I'd suggest to present your ideas to Mother Honda , which might provide obvious benefits for the owners of incoming models . Until now the only few motorcycle companies offer such a displays . Kudos for sharing . I might follow your improvements , so please do not hide any future and so "bright" enlightenments ...
I think Honda could have very easily made a better TPMS but that they have their reasons for deciding not to do so. It's a shame really, considering that tire pressure is so important on bikes.
I'm working on the RF link between the sensor transmitter and the display receiver. Once I'm past this, things should move pretty quickly.
I understand... but the information display is pretty much just a dummy light.
I think they could have done better than this but maybe they think just a light is good enough; I want to see the numbers
Since such a valuable gadgets are so popular , idea of "beefing up" newly purchased bike would be more attractive , if buyer had option to chose and order any of desired and already available accessories , like : shields , seats , lightings , combination of colors , foot positioning , etc . It could attract the product , increase sale and add the value . But producers have different mind set , so it's never ending struggle . Such a "packages" exist in car's business and successfully help to make a choice .
This is looking pretty good guys... I've made some major progress.
I've finalized the software for the sensor/transmitter and have been running bench tests to find a good balance between how it operates and battery life. What I DON'T want is a system like what is currently on the market that only updates pressure info every 5 minutes, yet still can't make their battery last more than a year or two. Whoever is putting systems like this on the market is either using really old technology or they don't know how to write good software.
I have this sensor programmed to measure pressure and temperature every 3 seconds and then transmit every 30 seconds. This is a pretty busy schedule for a sensor but I'm only drawing 12.5 uA (microAmps) to do this. Figuring a coin cell battery rated at 550 mAh, my calculations are EASILY exceeding a 5 year battery life. If I lengthen the transmit interval to 60 seconds or go to a 1,000 mAh battery, I think I can get 10 years out of this sensor.
With that said, long battery life is just the icing on the cake. The actual cake is having a system that'll keep you safe. Gradual pressure loss in a tire is one thing, but a blowout at highway speeds is something different altogether... and this is what I'm focused on.
At the end of every measurement cycle (3 seconds) the sensor compares the new pressure with the last pressure measurement and if there's more than 6 psi difference it'll send an alert to the receiver to light up the dashboard LED. For this to work, the LED has to be bright enough to be noticed in all riding conditions, it has to be mounted within your field of view, and you better be ready to immediately get off the gas if you ever see it light up.
What do you guys think?
Is 3 seconds short enough to catch a catastrophic tire blowout?
Is 6 psi a reasonable pressure difference to check for?
Any other thoughts?
Here's the LCD display wired to the receiver; I think it's a fairly good match to the OEM LCD. There's no pretty pictures, cute graphics, or any other extraneous distraction. It's there to give you tire information clearly and quickly, nothing more.
I currently have it configured to show front tire pressure and temperature on the top row and rear on the bottom row. Psi and Fahrenheit are shown; kPa and Celsius will be available for our metric friends.
The LCD is shown with the backlight off. The little blue box with white wires coming out of it is a potentiometer connected to the backlight control. I'm currently looking into an ambient light sensor that will automatically adjust the backlight when it gets dark. I'll bet some people will want it lighter or darker than others so I plan to have a manual control present also.
I was initially concerned that the characters would be too small to see well but I don't think that's the case. If you see good enough to ride, you'll be able to hold this at arms length and read it quite easily.
After seeing how well this little sensor does at drawing small battery current, I'm ditching the idea of adding an LF controller to the system. I initially planned to add an LF controller for two purposes: 1) to shut down the sensor when the bike is parked and 2) to allow the rider to request a pressure reading before getting on the bike.
Reason number 1 is unnecessary; as it's turning out, the sensor should run continuously for more than 5 years and not need to be turned off.
Reason number 2 will be baked in; since the sensor will run continuously, I'll make the receiver continuously capture data even when the bike is turned off. When you turn the bike off, the display will shutdown but data will continue to be captured in the background. When you get up in the morning and turn the key on, that will turn the display on and show the most recent tire pressure.
Interesting; I haven't considered an audible alert. I'm assuming you mean an audible alert in the bike's sound system.
When the receiver detects an alert status from the sensor, all it can do is turn on a signal. With an LED the process is simple; all that needs to be done is to use this signal as the power source for the LED. Receiver detects an alert... turns on a signal... the LED gets power and lights up.
However, even my digital multimeter generates little beeps when I press buttons on it. There has to be simple tone generators out there that can be used here. Receiver detects an alert... turns on a signal to power the tone generator... sound is created. Hmmm... yes I think that's a possibility! The output of the tone generator would just need to tie into the sound system.
Now that I'm past the hard part, these will be easy to make, and the more I make the cheaper I can offer them. I currently have these built on generic prototype PCB's from Amazon but for ruggedization for automotive use these will need proper PCB's made which are cheaper in higher volumes.