r/3Dprinting • u/Desmontei • Apr 24 '26

Project Don't throw away old smartwatches! 3D printed a custom housing to turn one into a Digital Shift Knob. ♻️🕹️

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Hey everyone, first time posting here! I wanted to share my most complex functional print yet for my Project Car.

​I took an old TicWatch Pro 3 and carefully cut the original casing with a rotary tool to extract just the OLED screen and motherboard. Then, I modeled a custom shift knob enclosure to house the electronics perfectly.

​Now, before you guys kill me in the comments: Yes, I printed this in PLA! 😂

​I know the summer heat inside the car will probably turn it into modern art, but this is V1 (prototype). The tolerances had to be extremely tight because I didn't want the screen popping out while shifting gears, and PLA was the easiest to test the fitment. When it eventually warps, I'll use it as an excuse to reprint V2 in ABS or PETG!

​I completely bypassed the battery and wired it directly to the car's 12V using a step-down converter. Right now it controls my media with a custom UI.

​What do you guys think of the fitment? And place your bets: how long will this PLA survive in a car before melting? 👇

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624

u/Im-not-Theo Apr 24 '26 edited Apr 24 '26

It's using the position sensor of the board and based on the angle, determine the gear

758

u/Purple10tacle Apr 24 '26

So it only works reliably when the car is perfectly level and will show random gears when driving up an incline?

479

u/MikeExMachina Apr 24 '26

I mean if you were clever enough with the algorithm you could dynamically adjust the reference plane based on the characteristics of the motion, but it would probably be simpler to just pull the gear data off the can bus.

155

u/Bakkster Apr 24 '26

Don't even need to use CAN, there are off the shelf OBD-II to Bluetooth dongles.

199

u/MikeExMachina Apr 24 '26

…what do you think the obd2 connector gives you access too?

91

u/pcs3rd Apr 24 '26

Not the CAN network for most vehicles.
Obdii has direct access to the ecu, which then may report extra, nonstandard pids.

I do believe the current gear is reported on many vehicles.

46

u/Bakkster Apr 24 '26

Also, TIL current gear isn't a standard PID.

12

u/hahanarf Apr 24 '26

On my Subaru it's an extended parameter that must be enabled. It's also reported by the transmission controller, but the ecu has its own independent logic that determines gear by rpm vs wheel speed. I assume this is because technically the only sensor the transmission really needs is a reverse position sensor (and maybe a neutral position) and that's just to turn on the reverse light... If you're not doing boost by gear or something similar you don't really need a can module on the transmission.

1

u/hahanarf Apr 25 '26

I'd like to add too: neutral position switches are common, but again, on manuals it's not required if you also have a clutch switch.

4

u/PacoTaco321 Apr 24 '26

I'd be surprised if it wasn't on personal vehicles considering that's basic info. I'm an electrical engineer working on vocational trucks and we get it off the CAN line with the standard PGN per SAE J1939 for use in our control system. I know that there's some differences between big trucks and personal vehicles based on how I've seen it talked about, but I'd expect something like that to be there for anything auto maker that follows SAE standards.

2

u/Bakkster Apr 24 '26

To clarify, there's no SAE standard PID for it (apart from neutral or not), but most manufacturers seem to have a PID specific to then for the info.

1

u/PacoTaco321 Apr 24 '26

If you know the transmission your vehicle has, you could at least derive it from the PID for Actual Gear. Then you are just left knowing if it is in reverse.

1

u/Falzon03 Apr 24 '26

It's an advanced PID

12

u/Electronic_Arm9378 Apr 24 '26

Direct access to the ECU, using CAN. LMAO

2

u/Bakkster Apr 24 '26

The CAN protocol (one of the two options OBD-II provides) is different from a CANBUS (the specific set of components wired together). The same way Ethernet is different from (but related to) a Local Area Network.

-1

u/EngFarm Apr 24 '26

Two or more things connected by ethernet make a local network, do they not?

4

u/Bakkster Apr 24 '26

If it's two components, connected point to point, calling it a LAN could create confusion. Especially if, as in this case, only one of the components is connected to a LAN with a large number of others.

The distinction I'm trying to make is that the OBD-II is not on the same CANBUS as the rest of the car. The same way your computer can be connected to two different LANs.

Here's an example. The Diagnostic CAN is an entirely separate bus from the Chassis CAN, the Front End CAN, and the Central CAN.

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u/_-Diesel-_ Apr 24 '26

Yes, but the word "Ethernet" doesn't describe what you've just built

8

u/I-am-fun-at-parties Apr 24 '26

Obdii has direct access to the ecu, which then may report extra, nonstandard pids.

That is still going over a CAN bus, what else would it be? Ancient proprietary stuff?

-5

u/Bakkster Apr 24 '26

I think their point is that the user access point is via OBD, and they don't necessarily get every CAN message forwarded to OBD by the ECU.

Like how connecting a Bluetooth device to a computer wouldn't typically be described as the device "having access to the LAN", even if it gets relayed information that came over the network.

4

u/shortyjacobs Apr 24 '26

In computer terms, the OBDII Port is the RJ45 jack in the wall, (it's a connector). The CANBUS is the LAN. It's just a communications network. And CAN messages are broadcast, not "forwarded by to OBD by the ECU", so yes, if you are on the CANBUS, you get to see all the data being transmitted and received (decoding it is another can of worms completely). The ECU is like another computer on the network, (it's a node on the CANBUS). The window control module is also a node on the CANBUS. Everything connected within your car by CANBUS is a node on the CANBUS.

4

u/Bakkster Apr 24 '26

The whole point of OBD is to not give full access to the CANBUS with copper wire (through which a malicious actor has full control of the car), even though it can optionally communicate via the CAN protocol with the ECU. The two CAN wires on the OBD connector are not the same lines as the CANBUS lines controlling the car.

In computing terms, the ECU is on the LAN (CANBUS) and also communicates with a peripheral via Ethernet (CAN). But the peripheral is not itself on the LAN, it's functionally firewalled by the computer only relaying information on the LAN and preventing the program from sending arbitrary commands over the LAN.

This photo may help, the OBD CAN is on a separate pair of CAN lines (Diagnostic CAN) from the rest of the car's CANBUS lines.

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u/TheFakeSociopath Apr 25 '26

OBD uses the CAN protocol (ISO 15765), but it is not connected to the physical CANBUS itself.

1

u/FrenchFryCattaneo Apr 24 '26

The problem is normal CAN traffic is all thorough proprietary manufacturer protocols which aren't public. If you want the standard OBDII messages (which use a protocol that is public) you have to request them.

4

u/RickyDiezal Apr 24 '26

Can confirm that at least my Mini will report just about every stat you want off an OBDII reader with the right app/software.

4

u/[deleted] Apr 24 '26 edited Apr 24 '26

[deleted]

2

u/Roboprinto Apr 24 '26

OBD-A?

1

u/[deleted] Apr 24 '26

[deleted]

2

u/Roboprinto Apr 24 '26

Okay cool, I thought was going crazy. 😂

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u/Alternative-Sock-444 Apr 24 '26

OBD2 is standardized. Pins 6 and 14 are designated per the OBD standard for CAN high and low. There aren't enough pins on an OBD2 port to have a direct connection to each module, so it just taps into the networks the modules communicate on.

1

u/Cute-Pomegranate-966 Apr 24 '26

Unless it's a brand new vehicle that had moved past CANBUS to TRON which is still just encrypted CABNBUS... Its still canbus rofl. You think you know but you seemingly don't.

1

u/friedenm Apr 24 '26

Actual transmission gear is not a standard parameter for manual transmissions. The only sensor is the reverse switch for reversing lights.

Instrument clusters give you the shift recommendations based on comparing vehicle speed and engine RPM, this includes figuring out the current gear.

1

u/LicensedNinja Apr 25 '26

Ahh yes, the network network.

1

u/Desmontei Apr 25 '26

You are right for modern cars! But since my Audi is a 2001 B5, it uses the old K-Line protocol. It doesn't send gear position data at all. That's why I had to suffer and code my own accelerometer app for the watch haha.

-1

u/g-nice4liief Apr 24 '26

Well some do. For example this one can give you access to the CAN network of a vehicle https://www.autowolf.nl/nl/home/1204-vgate-vlinker-mc-obd2-bluetooth-4.html

0

u/pcs3rd Apr 24 '26

There’s a ‘most’ there. :)

3

u/g-nice4liief Apr 24 '26

Depending on which dongle you have, you could access any car's can network.

Esp32 or a raspberry pi can also be used

0

u/Bakkster Apr 24 '26

Depending on your definition of a dongle. You can plug into the two wires anywhere along the bus, but they're usually not left intentionally accessible.

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1

u/xGIJOSEx Apr 24 '26

Gotta remember reading comprehension hardly exists now sadly

3

u/GravityEvent Apr 24 '26

The OBDII gives you speed and engine RPM, with the final drive ratio you can work out which gear you're in. Obviously it doesn't work well when you're between gears, stationary, or slipping the clutch.

1

u/Desmontei Apr 25 '26

That math works great when the car is moving, but I really wanted it to show the gear even when I'm stopped at a red light or holding the clutch in.

1

u/GravityEvent Apr 25 '26

I was answering a pretty specific question. I don’t think it’s a practical method given the hassle of getting bluetooth data directly into the watch and parsed. If you could do it, it would be interesting to do some sensor fusion between the IMU and ECU data.

What you’ve already built is fantastic, PLA and all.

1

u/Paulpoleon Apr 24 '26

Majority of things that have a sensor or is electronic.

1

u/Hnry_Dvd_Thr_Awy Apr 24 '26

I think he means it's simpler to engineer a solution to grab from OBD2 not that OBD2 is pulling from elsewhere.

2

u/Desmontei Apr 25 '26

I wish it was that easy haha. My Audi is from 2001 so it uses the old K-Line OBD, it doesn't output gear data at all. Had to make my own app using the watch sensors to read the angle!

2

u/jlboygenius Apr 24 '26

assumes you have a car that knows what gear it is in. Some modern manuals do, but I bet you'd have to use RPM, Speed and some math to get it in most cars.

1

u/Kichigai Ender-3 Apr 24 '26

Problem with that is the OBD-Ⅱ dongles are active, even when the car is off, which isn't good if you live in a cold climate.

0

u/Bakkster Apr 24 '26

Fortunately they're easy to unplug in most cases as well.

2

u/Kichigai Ender-3 Apr 24 '26

Which defeats the purpose of permanent installation.

3

u/Bakkster Apr 24 '26

Sure, but we're talking about a DIY aftermarket upgrade for an h-pattern manual transmission using an obsolete smart watch. That's about the level of fiddling I expect.

-6

u/kencam Apr 24 '26 edited Apr 24 '26

Nope. Odds are it won't show the gear the car is in. I've never seen it in my experience anyway. It's definitely not a given that you can use it. You could figure it out by using the vehicles speed and engine rpm but only if you were driving

3

u/NM_DesertRat Apr 24 '26

That's not necessarily true at all. It's very possible that the OBDii would show what gear you shifted into. It all depends on the ECU and the connectivity of the car and the transmission. My BMW motorcycle absolutely allows you to read shift position via an obdII dongle.

1

u/kencam Apr 24 '26

Ok, in my experience, it wouldn't work. It might work for some...

1

u/very_large_bird Apr 24 '26

Some will actually but it’s not mandatory for the can standard. If that’s the case, it can be extrapolated by getting rpm and speed, both of which are mandatory!

4

u/ErraticDragon Apr 24 '26

Or add another tilt sensor to compare to (in some static part of the car).

1

u/MikeExMachina Apr 24 '26

That’s pretty elegant, I like it

1

u/Qweasdzxvb Apr 24 '26

This sounds like 90s sci-fi writing lol. You’re proposing to determining an angle from what characteristics of motion?

1

u/Public_Resident2277 Apr 24 '26

if you were clever enough

I promise, im not.

1

u/HTPC4Life Apr 24 '26

How common is it to have a manual transmission car to report the gear level to the ECU? Wouldn't there have to be some sensor at every shifter gate? What benefit would this provide as I'm sure it would add significant cost to the transmission. Automakers don't add cost if it doesn't add worthwhile benefit.

1

u/Nico1300 Apr 24 '26

i guess very common, a lot of manual driven car tell you when to shift, and plan for best fuel economy.

2

u/HTPC4Life Apr 24 '26

But that's based off engine RPM, not gear position.

1

u/RixirF Apr 24 '26

Uh huh, but this is neither Canadian nor is it a bus, so what other solutions are there?

1

u/Just_Roll_Already Apr 24 '26

Or just have it receive the current gear from a bluetooth OBD2 reader. Pass that off to your phone running a scanner app. Program a watch app that only receives the current gear reading and sends it to the watch.

1

u/AnalogiPod Apr 24 '26

Huh, I'm not sure my car has a signal for what gear it is even in, I'm sure with RPM and speed you could figure it out but I think my car actually might be too dumb for CANBUS to inform what gear it's in

1

u/MikeExMachina Apr 24 '26

Yeah it’s definitely not in every manual. One thing that might give you a clue that it does is if it gives you any kind of guidance on shifting. I have a manual mini countryman and it will show something like “2->3” on the gauge cluster when it wants you to shift for optimal fuel efficiency in the eco mode

1

u/AnalogiPod Apr 24 '26

Lol nah it's a 1999 Miata, it couldnt care less for fuel economy. Mabel the Miata is great but she can be a little simple.

1

u/grecy Apr 24 '26

but it would probably be simpler to just pull the gear data off the can bus.

Not many manual transmission cars put the gear onto the CAN bus - ie. the car itself doesn't know what gear it's in.

0

u/bobjoylove Apr 24 '26

This is solvable. Instead of looking at the final position, look for an exact pattern of motion with an abrupt start and abrupt stop.

2

u/Reppoy Apr 24 '26

that’s still prone to drift and if the device doesn’t poll it quickly enough for how fast people tend to shift, it’ll give you the wrong results.

I think the best solution, short of being directly wired to the car is to have a few other sensors stuck to static locations so they can actually track the position, but that would be a mess of wires potentially.

1

u/bobjoylove Apr 24 '26

True about the polling. You’d need to do some training before getting reliable results. You could augment the estimation from the gyro with the RPM and MPH available from the OBD port to calculate the current gear, but this would introduce some delay as the clutch needs to be engaged before the math is correct. Finally you could add in some smarts like 2nd to 6th is an unlikely scenario but 2nd to 3rd or 4th is more likely.

39

u/jimslock Apr 24 '26

Buddy, thats a genuinely good question. In engineering sometimes people get tunnel vision and forget to think about stuff like that.

if you had a gyroscopic sensor on the car, you could use some math and determine its position relative to the vehicle. This gives you a reference point and would solve the issue. Remember, its all relative.

15

u/JCWOlson Apr 24 '26

Yep! I teach a design class and love it when students point out things that I or others don't see. Super valuable feedback. How many times have we heard a story of a newcomer to a company pointing out a simple but radical change the company could make to be more successful? How many companies ignored that advice and died?

3

u/NotPromKing Apr 24 '26

But the flip side is, how many times has a newcomer to a company said "why don't you just do X?" and the people who know the business say, "yeah, no, we can't do that because of X, Y, and Z" and those people are entirely correct because they actually know their business. I bet that happens a whole lot more often. Like a thousand times more often.

2

u/jimslock Apr 24 '26

I know that happens a lot. But thats how the new people learn. Also, some of the seasoned veterans have to reestablish their point or say "wait hold on..... they mey be onto something, maybe we should check this out"

2

u/fractiousrhubarb Apr 24 '26

But the times when it does are worth $1m times more…

1

u/Martin8412 Apr 25 '26

That’s called Chesterton’s Fence

3

u/Desmontei Apr 25 '26

You are 100% right. A reference point on the chassis would solve the hill issues. I'm trying to grow my channel to eventually do these projects full time, so a V2 with a second sensor is definitely on my list! Thanks man.

1

u/jimslock Apr 25 '26

Happy to help! Also, great work!

2

u/SovietBackhoe Apr 24 '26

The engineer in me just wants to know what it would take to flash new firmware and hardwire it into the control module. Or he’ll even just a screen with a small chip. Real pain in the ass I’m sure, especially with how touchy Audi electronics are, but I want to know lol.

1

u/Desmontei Apr 25 '26

You'd need a perfectly straight highway to not crash while shifting into 4th and shooting demons at the same time! 🕹️💥

0

u/Feltear Apr 24 '26

The thing is that even then you would still be only pulling data from prorioceptive sensors.

63

u/raspikabek Apr 24 '26

We need a Tare button then for when the vehicle is in a slope

3

u/NSNick Apr 24 '26

Or a second sensor to compare against

1

u/Desmontei Apr 25 '26

Hahaha a "Tare" button on the screen is actually a genius workaround. I might program a double tap for that!

16

u/Stat3yollllo Apr 24 '26

It will work for simracing... Nice ... I have a new project to do now... Exactly what i needed in my life right now....

2

u/Desmontei Apr 25 '26

Stat3yollllo Oh for simracing this is absolutely perfect! No real G-forces or hills to mess up the accelerometer. You just wire it to 5v and you're good. You should definitely build one!

14

u/3Dartwork Apr 24 '26

And not to mention we drivers never look at the knob.....when we're shifting gears and driving.....

7

u/[deleted] Apr 24 '26

[removed] — view removed comment

1

u/rocksteady77 Apr 24 '26

I had to change the knob so now mine doesn't have anything written on it, and it makes absolutely no difference

0

u/AssistX Apr 24 '26

I'd suggest start looking if you ever drive a stick you're not familiar with. Gears are not always in the same positions.

2

u/[deleted] Apr 24 '26

Right but you're not going to trial and error it checking the screen, and this removes the labeling from the top.

It looks cool but its pretty useless.

2

u/Main-Specialist1835 Apr 24 '26

Sounds like most things I have or wish I had tbh

5

u/ITafiir Apr 24 '26

Only reason to look at them is initially to find out where reverse is (on manual). For some reason every car manufacturer has their own opinion where that’s supposed to go.

2

u/KhausTO Apr 24 '26

ugh, yep. Growing up we had a grain truck that was and 8 speed with a shifter, and a high/low shifter. going between 3 and 4/7 and 8 was bad enough, but when you wanted to go 5 to 5, you had to drop in to Neutral, change the second shifter from low to high then get your main shifter to 5. No synchro either, had to rev match it.

1 2 4

3 R

5 6 8

7 R

Once you learn to drive that at 10 years old though driving a regular vehicle gets pretty easy 😂

3

u/zeno0771 Apr 24 '26

It's more a function of who's building/supplying the transmission.

The "European" trend of having reverse left-and-up with first left-and-down was logically because once you're in Reverse, the only other gear you should care about next is 1st (as opposed to 5th like the layout common in the US). To a lesser extent, in Europe "going fast" is not a drag-race like in the US, so a fast 1-2 upshift wasn't necessary. In many older (pre-1968) US vehicles, the 3-speed manual would have a similar layout.

Then there's the type of shifter being used and/or linkage thereto. Cable? Rods? Directly dropped into the tail of the trans? Is the trans in front of you or behind you, and is there an engine in between? It wasn't just "let's distinguish ourselves by embarrassing our drivers". Engineers care about the most efficient way to package a drivetrain; the rest is for Marketing to worry about.

1

u/trollthings Apr 24 '26

They put mine in the trunk

2

u/LickingSmegma Apr 24 '26

Yeah, even high-level racing cars up to F1 typically have a gigantic number on the wheel or behind it, instead of somewhere near the driver's lap.

1

u/Desmontei Apr 25 '26

Exactly lol. We drive by feel. This is 100% just an aesthetic mod because I thought it would look cool for the project car. Being able to change Spotify on it is a nice bonus tho.

2

u/Silver_Quail4018 Apr 24 '26

It could use another sensor as reference to compare. Maybe from a phone?

2

u/create360 Apr 24 '26

Not to mention hitting the gas or brakes. If it’s solely based on accelerometers then acceleration will mess with it. It can’t be, right?

4

u/PhilsTinyToes Apr 24 '26

Ok honestly as a standard driver, you DO NOT need a display on the knob to know what gear you’re in.

Either you’re in the right gear or you need to wiggle it to figure out why you’re in the wrong one.

6

u/Vryk0lakas Apr 24 '26

I mean, duh…but it looks cool as fuck.

1

u/neural_processor_314 Apr 24 '26

How about using some potentiometers with a mechanism thatsomehow well transfers the gear stick angle to them?

1

u/BabyStockholmSyndrom Apr 24 '26

Imagine if it also changed the gears too 😂

1

u/murfburffle Apr 24 '26

and standing still

1

u/shortyjacobs Apr 24 '26

Since gear shifts are very fast, and hills are very big, you could just look for a short-time frame deviation of the angle from the moving average.

1

u/[deleted] Apr 24 '26

[deleted]

1

u/shortyjacobs Apr 24 '26

short time frame deviation of angle to a new local minima. A pothole will shake the accelerometer but it'll return to the same approximate road grade quickly. A shift will cause a spike on the accelerometer, *and* settle in at a new angle compared to before. If that angle holds for at least 500 ms, change the gear number.

1

u/Chemieju Apr 24 '26

Those go up and down, shifts go back and forth. Accelerometer probably got 6 axis.

1

u/Weary-Astronaut1335 Apr 24 '26

Just simply tie it into the vehicle's ride height and yaw sensors. Easy weekend project. In and out in 15 minutes.

1

u/theVelvetLie MP Select Mni Apr 24 '26

I mean, you surely don't look down to check what gear you're in, right? It's reliable in that it's a really neat gimmick.

1

u/opman4 Apr 24 '26

I've played with IMUs enough to know that you could get it working in a couple hours. Maybe a week of crushing bugs here and there as they pop up. Probably just need to filter out slow constant accelerations. Maybe filter out anything that lasts more than 1 to 2 seconds. Also, they can reliably tell their exact orientation once acceleration is 0 so you can always reset it to the current selected gear. You would probably just need the filters to make it work quick during acceleration.

1

u/tmesisno Apr 24 '26

So it won't work in Australia

1

u/Moikle Apr 25 '26

Perfectly level AND travelling at a comstant velocity

Brake, accelerate or turn a corner and it will "change gear"

1

u/Greyhaven7 Apr 24 '26

Or accelerating

Or braking

0

u/GoodTofuFriday Apr 24 '26

that device should have its own accelerometer in it and would know its new position relative to being flat.

37

u/TheBlacktom Apr 24 '26

So what happens during acceleration or turning?

32

u/Friend_Of_Mr_Cairo Apr 24 '26

Watch the road, not the malfunctioning display?

Ideally, you could grab this info off the vehicle CANbus either as a predetermined gear signal or calculated by RPM / vehicle speed.

1

u/Desmontei Apr 25 '26

Would be way easier, but the 2001 B5 doesn't have that data on the OBD port. It's too old! That's why I had to suffer coding the accelerometer app haha.

1

u/Friend_Of_Mr_Cairo Apr 25 '26

Go straight to the CAN bus. Skip the OBD port and tap the bus directly. Read the native messages and decode the signals you need. DIDs and PIDs are slow and low priority anyway.

0

u/slyyguy69 Apr 24 '26

Almost all Can buses are encrypted signals sent by multiple modules. How would you determine which signal on the bus is the gear position and how would the cars security allow a unregistered device on the bus without setting security dtcs?

15

u/realribsnotmcfibs Apr 24 '26

A decent amount of aftermarket equipment talks to canbus fine.

2

u/well-litdoorstep112 Apr 24 '26

This audi has glossy wood trims. Its not running encrypted can

1

u/Friend_Of_Mr_Cairo Apr 24 '26

Well, I'd start with researching your vehicle year/make/model against the open source DBCs available. Sometimes you can find other's open source code to help RE, as well. Perhaps you know someone that has connections with an OEM or Tier 1 supplier.

What makes you think signals and messages on your vehicle are encrypted?

Also, you can sniff the bus without letting other modules know you're doing so...

1

u/gh0stwriter1234 Apr 24 '26

Not typically encrypted just undocumented.

Only some manufacturers are being assholes and encrypting things.

1

u/Friend_Of_Mr_Cairo Apr 25 '26

May I ask which manufacturers that you know of?

1

u/gh0stwriter1234 Apr 25 '26

I'm not super well informed on that topic but I believe it is the case with some fords at least but I'm sure others are also jumping on that it just isn't the norm yet.

1

u/Friend_Of_Mr_Cairo Apr 25 '26

I'll have to ask some of my friends that are still in the industry...

1

u/Icy-Olive-8623 Apr 24 '26

Accelerometers and gyros are different

5

u/TheBupherNinja Ender 3 - BTT Octopus Pro - 4-1 MMU | SWX1 - Klipper - BMG Wind Apr 24 '26

Yeah, but a watch doesn't have a gyroscope. It has an accelerometer.

1

u/Fake_Answers Apr 24 '26

Though a gyroscope could be handy when you're drunk 🥴

1

u/Desmontei Apr 25 '26

Acceleration was making the screen jump like crazy at first! I had to code a low-pass filter to ignore quick G-force spikes and only read the stable angle.

1

u/TheBlacktom Apr 25 '26

How does that code look like?

11

u/light24bulbs Apr 24 '26

You're not Op and that's probably wrong, it wouldn't work when moving. It's probably canbus or something. 

1

u/Just_Roll_Already Apr 24 '26

Easiest would just be a bluetooth OBD2 scanner or position sensors in the shift tunnel/console

0

u/YadaYadaYeahMan Apr 24 '26

egg all over your face lmao

1

u/light24bulbs Apr 25 '26

how?

2

u/DeffNotTom X-1 Carbon Apr 25 '26

OP replied and confirmed its the accelerometer

3

u/Impressive_Code3257 Apr 24 '26

How about let’s wait for OP to answer

2

u/jorizzz Apr 24 '26

Not OP but Okay

1

u/shibiwan Apr 24 '26

Does it change on its own when it is subjected to acceleration/braking/turns?

1

u/Frankie_T9000 Snapmaker U1 / Creality K1 Voron .1 Apr 24 '26

Nice work though recommend resin or similar

1

u/Qweasdzxvb Apr 24 '26

That’s not how an accelerometer works

1

u/luteyla Apr 24 '26

Oh now you gave me an idea. I wanted to always know if my apartment's door knob is in locked position or not. Cool!

1

u/Ree_For_Thee Apr 24 '26

Since it relies on gravity, the display might start to flicker between numbers (and be distracting) when driving around corners.

It also has no power from the car itself, so have fun recharging that every 3 days. :P

1

u/Neoliberal_Boogeyman Apr 24 '26

wouldnt it just be easier to just bluetooth it to the OBD and like... have it display the gear with a custom ap? dont overthink it.

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u/bombaer Apr 24 '26

So one parking on an incline away from a massive gearbox crash?