Project Feasibility: Digital Shifter Knob

Hello all,

The whole concept of arduino has intrigued me ever since I first saw a kit in radio shack and learned about what it was. I always had a nagging desire to learn about it but never really knew what I would do. I recently had an idea that would allow me to learn arduino while creating a fairly unique bit to fit into my car. Of course I could buy one and fit it to my specific vehicle but wheres the fun in that? And this way I'd be killing two birds with one knob (making something with and adding something fun to my vehicle)! Puns aside, I am asking about the feasibility and difficulty level of a project I have in mind. I saw in my travels on the internet a shifter knob for 5spd manual that featured an LCD screen that displayed the current gear. It works, from my guess, by a gyrometer/accelerometer and determined the gears by what angle the stick is in. After installing, the instructions require that the knob be "calibrated", which is what makes me believe that a gyrometer/accelerometer is involved. Link http://www.americanmuscle.com/digital-shift-knob.html?utm_campaign=bazaarvoice&utm_medium=SearchVoice&utm_source=RatingsAndReviews&utm_content=Default

My project involves crafting my own board/components and fitting them into a custom made shifter knob. I am asking the forum if this is a feasible idea? If so is there a place to start? I am eager to learn but I do not know where to start. I know how to solder and have the basic tools but when it comes to creating boards/programming them, I am in need of guidance. Specifically what type of components I would need and any guides on how to configure them?

Thanks for any of your time/input!

Hi

Interesting project. I wonder if it does do as you suggest, how it deals with climbing a hill or up a ramp where the change of angle would be presumably similar to shifting a gear? If you're on a bumpy road can you presume it would misread (or I wonder if calling it a Mustang part guarantees nothing but smooth asphalt underfoot so that's not an issue).

There are several inexpensive 6DOF sensor modules which could be used to deliver your gyro & accellerometer reading. For the sake of the purchase it would be worth wiring up a temporary rig and seeing if your idea is feasible with that kind of thing, in the space available to you.

Cheers ! Geoff

I love this forum you guys are so bright! I never would have thought of something like that right away! Indeed, it would be going into a WRX which would mean quite the opposite of smooth, level, asphalt all the time 8). I Wonder if there would be way to program it to only change if it senses the gs of the stick being shifted. There must be a different amount of force in the change of angle associated with a gear shift than with a hill? Unless I accelerate hard on a steep hill or I go over a bump or something? I did some reading about how programming one of the gyrometer/accelerametor chips works and it seemed that it was always checking to see if there was a change of angle and the increase in G's sensed while the change of angle occurred? Does that make sense? This is all very new to me. I read that here: http://forum.arduino.cc/index.php/topic,58048.0.html

I had found this: https://www.sparkfun.com/products/10121 which is pretty small. What would that little board be connected to?

Edit: I just thought... It would still probably require me to avoid changing gears on a hill.... I wonder how that product deals with it (if at all) in those situations. I should see if the cars ECU keeps track of what gear the car is in? If it was connected to the ECU, a gear shift indicator light could also probably be programmed into it as well. That would be cool.

I would not expect that an accelerometer/inclinometer based approach would be feasible, because a car cannot be assumed to be level and at rest.

The easiest and most reliable approach would be to fit a set of switches to the base of the gear stick to detect the physical position of the stick relative to the gate.

How much work are you prepared to do to install this? (If you require it to be entirely self-contained within the gear knob you'd be eliminating a lot of the easier and more reliable approaches.)

Tip 1 - keep post to the point - no need for the life history, here you are dealing with techs who enjoy the tech.

Tip 2 - by that starter kit and have fun learning and you have a great deal of learning to do!

Tip 3 - buy some add ons, an accelerometer for example

Mark

The other way you could to this is to fit Hall sensors to the input and output of the gearbox, or tap into the engine tacho signal and the speedometer signal. Then you can measure the rpm before and after the gearbox, and hence compute the gear ratio.

dc42: The other way you could to this is to fit Hall sensors to the input and output of the gearbox, or tap into the engine tacho signal and the speedometer signal. Then you can measure the rpm before and after the gearbox, and hence compute the gear ratio.

a CAN bus interface will help with the rpm and road speed. Possibly all the info you need to derive your gear selection could be there? Then all you need to house in your gear knob is the display.

Geoff

How about doubling your fun and adding a second accelerometer, mounted to the body of the car ?

That way you can monitor the difference between the two, to show where the gear stick is, and at the same time monitor the realtime g-loads on the car during the stage.

With a data logger, you should be able to play them back.

I guess the gear changes aren’t going to be too smooth, so you might also be able to monitor for “knock” in certain directions, to add a level of sanity checking to the gear position: ie, if there’s a sudden bump forward, you’re probably now in 1st, 3rd or 5th, and a bump backward means you’re in 2nd, 4th or trouble…

Adrian.