Tesla CAN bus data logging-----make money online

today on Applied Science I thought we'd

talk about extracting information from a

modern cars data bus so we are sitting

in a new Tesla Model S on this rainy day

and I thought I'd talk about what I've

learned and how I plan to build a system

that will show the data on the cars

existing console it's pretty normal of

course for a car to show you the speed

it's going on the dashboard speedometer

but there's actually hundreds of other

variables that are commonly sent through

a car's data bus and some of them can be

pretty interesting so for example motor

torque in this car since it's electric

you can see the number of amps being

pulled out of the battery pack and

literally on and on so here if you know

something about car buses you may have

heard this term ODB 2 and this is a

somewhat standardized port that was

created mostly for emissions control

hardware and the Tesla has an ODB 2 port

in the drivers footwell but since this

car doesn't have an internal combustion

engine

there's no emissions equipment and so

there's really not much on that bus so

avoid that what you really want to do is

check out these two connectors that are

beneath the center console here there's

a little cubby hole that you can just

pull off there's two clips that just

snap down and it Tibbets in the back

just pull that off and then the smaller

connector is a four pin connector and

this is actually Ethernet so a couple

years ago when the Model S first came

out someone connected to this and

realized it was Ethernet and started

poking around in the cars private

network and then a couple months later

Tesla issued a firmware update and shut

this port off so what they did was they

disabled this at the cars Ethernet

switch so if you still want to get on

the card's Ethernet what you can do is

find the wires the Ethernet wire is

going to this center console computer

and input your own switch in there

basically tap into it and you can still

smooth the ethernet if you want but

we're not going to talk about that in

today's video what I'm most interested

in is this other connector which is a

can bus connector Tesla calls this a

diagnostic connector and there's

actually several can bus buses on here

if you haven't heard the term before

CANbus is used in the automotive

industry and it's more real time so

Ethernet might be good at sending

something like a an audio stream that

you're going to play on the the cars

sound system whereas the can bus is

actually carrying the low-level signals

that are connected to things like the

accelerator pedal the motor controller

indicating how much current it's using

and that sort of thing I spend quite a

bit of time piecing together all the

information needed to get this going and

I'll put all of it in the description of

this video feel free to ask me any

questions that there's actually not that

much information out there like for

example this connector is not a very

standard connector in fact if you can't

get this a digit key or mouser or

anything like that but after hunting

around on the Tesla Motor Club forum for

many many hours I found a seller who

actually has these connectors but thank

you very much for finding these and

making them available to hobbyists as I

mentioned this car has several different

can buses and currently we're going to

talk about canvas 3 which is the one

that carries drivetrain information so

motor power battery power accelerator

pedal position all that sort of stuff

and you can see currently the scope is

looking at what's going on on this

canvas canvas 3 and you can see a very

high rate of data going even though

we're just sitting here two cars

basically idling okay here's a closer

look at the scope and as you can see

there's a lot of data going by on the

bus here and this scope can decode all

the can bus information so if I turn bus

one on we set that up as a can bus and

the bitrate is 500k per second and it

can bus is in fact a differential

protocol it's two wires plus and minus

and normally the wire 0 is driven

differentially but interestingly on this

scope you only need to the sample one

half of the Lion

I guess it's good enough and so we can

do a single acquisition and you can see

there's data going by and so to make

this a little more interesting what we

can also do is set up the scope

that it triggers only on a specific

packet type so we'll go to the trigger

menu and instead of just triggering on

the edge of the waveform will trigger on

the bus and if this is b1 the can bus

and we're going to trigger on the

identifier so the identifier in a can

bus packet describes sort of which part

of the car it pertains to so I've

already set it up so that it's going to

trigger on a densifier hex 1:06 and this

is one of the drivetrain components I

think it might actually be the rear

motor controller what I'm going to do is

step on the gas that are the accelerator

pedal of the car and what you can see is

that this value changes well as I step

on the Tuttle the car is beeping because

it tells me I have to put it in Drive if

I want to go somewhere these other ones

are zero because we're not moving this

would be describing a motor torque I

think as you can see if I floor it this

goes to si so that's a maximum pedal

position and it's zero of course when my

foot is not on it another really useful

thing we can do with this scope is

capture a large quantity of data so if

we put the trigger type back to just

edge and I'm going to stop the

acquisition here and I'm going to change

the record length to a really high value

so when the scope was running really

quickly like that we're restoring a

hundred thousand data points and having

it just show this little section but

let's say we wanted to capture like 10

seconds worth of canned data to do

further analysis we can do that too and

it's all set

the Scopes memory to be 20 million

points and then I'm going to change the

time per division to be a much higher

value like 1 second so this should be 10

seconds worth of data so I'm going to

press the single button and this scope

doesn't show you in real time but

actually it is computing there it is

recording right now and so it's probably

it's been about 5 seconds since I

pressed it there's all the data and

what's happening is it says B 1 not yet

computed so in another few seconds it's

going to go through and figure out

all of the canvas messages for the

stream and there they are so if we

wanted to see them what we can do is go

to b1 this bus that we're decoding and

then go to the event table and this is a

list of all the messages that came in

during that 10-second acquisition and

hopefully it even shows what time the

message came in so minus 5 seconds I

have the trigger point set here and the

whole acquisition was 10 seconds so

minus 5 would be you know the first

thing that it saw and here's that

identifier column that I was mentioning

so if we scroll down through this list

of data there's the 106 and you can see

it was 0-0 if I have my foot on the

pedal this would be a different value

here so it's neat is that I can say I

can save this event table and it's not

highlighted right now because they don't

have a USB key plugged in but what I was

doing was collecting lots of data while

driving with a USB key in here I could

hit single really quickly and then go

collect some data and then after he

decoded all the canvas stuff I could say

a save table and it would save a CSV

file to the USB key then it can take the

USB key back to my computer and plot it

in Excel and I ended up with something

like this okay I know it's dark but

that's a quite a bit longer than I

expected I'll do another video in the

future with better lighting let me tell

you what's going on here I've got a

Raspberry Pi 3 and this I bought this

from copper Hill technologies and it

comes with a canvas shield so this is

connected directly to the car and it

even has a 12-volt decidable buck

converter so it's literally just four

wires connected to the car and

originally I was thinking well you know

I'll make another screen or something in

here kind of like this an extra LCD to

show the data that I've been vlogging

but really it's kind of annoying to

mount another screen and I've got this

huge 17 inch touchscreen built into the

cars - already so I started thinking

about ways that I could get the data

from the canvas onto the screen here now

Tesla house is pretty well locked down

however there is a web browser built

into it

and I started looking at ways that I

could get the canvas data from the

Raspberry Pi into the web browser and

this browser is WebSockets compatible

which means that I have a pretty low

latency pipeline between the browser and

the server so what I'm doing is I'm

running at node AF server

on the Raspberry Pi it's pulling data in

through the canvas shield in real time

and then this node j/s script is running

a server and the browser here is sucking

in the data so you can see it's actually

really responsive it's updating ten

times per second and I'm pretty sure it

can go much faster than that so I'm

doing is just stepping on the

accelerator pedal and you can see it's

updating nice and quickly there was a

couple of interesting gotchas along the

way that you might find interesting so

the way that I'm connecting the car to

the Raspberry Pi is through the wireless

network like I say I didn't want to hack

into the car I haven't touched that four

pin Ethernet connector and so the first

trick is that the car will not connect

to a wireless network that doesn't have

internet available or at least it seems

that way so to fix that problem I got my

Android phone and connected it via USB

to the Raspberry Pi and use USB

tethering from the phone so the

Raspberry Pi actually has internet now

through the wireless network on the

phone okay so now with routing and

everything the car will eventually get

to the Raspberry Pi through Wireless and

then from here to the phone and then out

to the Internet so that's all fine the

next interesting problem is that the

tesla browser doesn't allow you to

connect to local IP addresses so 192.168

whatever and they did that purposefully

I guess to keep you from you from doing

exactly what we're doing now I guess but

anyway since we have full control over

the router obviously this Raspberry Pi

is routing all the packets we can just

set up a static route so I've gone to

the address 42 42 42 42 and that just

reroutes all the packets to the local

host here and we can serve those packets

and the browser in the car has no idea

that it's talking to the Raspberry Pi I

think

talking to a public web server but this

seems to be a pretty good solution it's

very responsive and it just keeps

running it's not like I have to keep

reloading the page or anything like that

and so with a little magic you can

imagine what this is going to look like

you know the I'll have a graphing in

real time in the client-side and I'll be

able to do something like select

different things like you know if I

wanted to see acceleration over time

with motor torque and all that stuff I

could construct a graph in the browser

and that's that's what we hopefully

looking at next time

you

so in the next video we'll be talking

about the physics of the car a little

bit more the whole purpose of making

this data collection systems so that I

can record all the data from doing you

know kind of extreme things with the car

and then we can you know see what's

interesting with that okay I hope you

enjoyed that see you next time byeTop Paid Keyword :  earn cash online, google make money from home, earn money online without investment by clicking ads, free earn money website, online money making jobs, earn money online without investment by typing, online work for money, best online earning sites, make money online with google, online earning websites, money making websites, online earning websites for students, invest online and earn money, best online money making, online money income, view ads and earn money without investment