EEVBlog2 - Tesla Model S - Australian Test Drive

[robbak]

INB4 - Teardown!!!

http://youtu.be/6RRKWORDPxM

Seriously, that is a nice vehicle. Geek bling all over the place, of course; but why not!

[PChi]

Thanks for the video. I have seen a few in the UK already.

[German_EE]

So, can we expect to see the teardown on Tuesday? 

[SeanB]

Don't think they would have taken Dave's Toyota POS as a trade in on it, so likely not..........

[free_electron]

Some tidbits:
-The seats are actually made by an australian company.
-The car has front and rear distance sensors
- the instrument cluster runs on a Tegra 2
-the main touchscreen runs on Tegra 3. They communicate through ethernet. When music is playing the mai. Screen serves a webpage with album art that gets shown by the instrument cluster.
There are two other devices on that network : the car gateway and the gps .
You can reboot both cluster and touchscreen by holding down both rollers or both bottom buttons. This can be done while driving. The displays only visualise data. The drive computers controlling propulsion, braking et al are indpendent.
-the odb does not allow you access to the real can busses. They have a dedicated can bus only serving odb. Data is filtered. You have no access to the internal systems.
-the car a real ethernet jack in the fuse box , as well as wifi. The maintenance techs can go in that way. Don't try and get in... Somebody tried it and within 5 minutes got a call from service that the car detected a non standard device on its lan.... And please get off the network.
- each critical systems run on its own special dual core processor. One is 32 bit, the other 16 bit and they are not binary compatible. This allows trapping of software bugs (majority voting systems)

- certain data is being pulled live (anonymised) to study how people use their car and make improvements in software and hardware. Other data is pullable on demand in case of trouble. When you call service they ask for the last 5 digits of the vin number and your name and they log in remotely.

-the drive train uses IGBT as opposed to mosfets
-peak power deliverable by the inverter is 360 kilowatts at a max current of 1200 ampere. It can sustain this power all the way to top speed.
-peak regeneration is 60kilowatt pumping back in the battery.

- a nearly depleted pack (50km range left) at the supercharger is fed 350 odd volts at 330 ampere.
The pack is preheated and conditioned and current then rolls up controlled.
- they can actually sense the contact resistance in the charge connector. If that does not meet spec charging current is limited or charging aborted. To give you an idea .. 1 milliohm of contact resistance at 300 ampere would burn 100 wat tjust in the connector ... Can't have that...

[mikeselectricstuff]

Don't try and get in... Somebody tried it and within 5 minutes got a call from service that the car detected a non standard device on its lan.... And please get off the network.

But it's my ***ing car - I'll plug whatever in want!

The pack is preheated and conditioned and current then rolls up controlled.

Does that mean it's sluggish when starting on a cold day?

[EEVblog]

Don't think they would have taken Dave's Toyota POS as a trade in on it, so likely not..........

My Holden Vectra is worth about as much as it weighs in scrap metal.

[free_electron]

But it's my ***ing car - I'll plug whatever in want!

Warranty void . You do not want to lose your 8 year end to end warranty with unlimited miles...
Tampering is detected and cause for voiding warranty.

The pack is preheated and conditioned and current then rolls up controlled.

Does that mean it's sluggish when starting on a cold day?

Nope. The battery pack kept at optimum temperature at all times.
When plugged in and really cold they use shore power to actively heat the pack. When not plugged in and cold they still keep it warm at reduced setting. Once you start driving the pack heats up by itself due to some losses.
When warm they actively cool the pack.
To guarantee long life the batteries must not be charged cold or too warm. So when plugging in the battery manager first either preheats or cools the battery. Charging is thne limited to 40 to 80 ampere. Once the pack is in the correct zone they ramp up current to 300+ ampere.

[RobertoLG]

Man, that's a really nice looking bad boy! looks a bit like a masserati, nice video thumbs up!

[HighVoltage]

-the odb does not allow you access to the real can busses. They have a dedicated can bus only serving odb. Data is filtered. You have no access to the internal systems.

Can one access the OBD with a standard car OBD-II connector and software?
And what data would one get access to?

Very nice impression out of this video.
It will be time for me to drive one.

[G7PSK]

So there is the possibility of someone hacking the Tesla network and crashing the entire system including all the cars. I think I would rather have my car off net thank you.

[EEVblog]

So there is the possibility of someone hacking the Tesla network and crashing the entire system including all the cars. I think I would rather have my car off net thank you.

That's why Tesla were at the recent Defcon hacker conference. They offered a prize to anyone who could hack it.

[mikeselectricstuff]

When not plugged in and cold they still keep it warm at reduced setting.

How long would it take to self-discharge in this mode? Is there a way to tell it when you'll be back, to avoid wasting power?

[tom66]

So there is the possibility of someone hacking the Tesla network and crashing the entire system including all the cars. I think I would rather have my car off net thank you.

Drivetrain etc. completely isolated from the network. No way to crash the car via the network, only the touchscreen cluster (the dashboard would still work.)

When not plugged in and cold they still keep it warm at reduced setting.

How long would it take to self-discharge in this mode? Is there a way to tell it when you'll be back, to avoid wasting power?

It discharges about 2~3 miles per day, so Tesla recommend leaving it plugged in to avoid disappointment.

Once pack goes below 0 miles rated range (there's a small buffer) it'll stop charging the 12V aux battery and isolate the  battery contactors. In this mode it can sit for over a year without harm to the pack, although the car would need to be jump started (in the same manner as a petrol car with a flat battery, though it only needs a little power to open the contactors and start charging the HV pack.)

Only heats the pack when it goes below -30C. Tesla say 24 hour max at -30C, so I guess the battey will discharge very quickly, which could be damaging to it. All other times, pack is kept at ambient temperature. One downside, of course, is that getting into a cold car limits range. Range is reduced about 35% in cold weather until pack warms up. One trick is to turn on the cabin heating via your phone before leaving. This will also heat up the  battery. About 15~20 mins is usually good enough. Another option is to charge to 10% less than is required, then about an hour before leaving, finish the other 10%, which will also serve to warm up the pack.

In very cold weather, there is no regen braking (below 0C) as there is no safe way to charge a li-ion battery below freezing. Tesla haven't got any load resistor capability either; it would be nice if it could dump the power into a resistor, so it maintained the same feeling, even when regen is unavailable. Or, at least, use friction brakes.

[German_EE]

After watching the review there is only one thing I do not like on the car, the lack of a manual handbrake (a.k.a. Parking Brake). Most cars have dual circuit brakes plus the handbrake connected to the rear brakes via a cable that needs tightening now and again, but with the Tesla that ability has been removed.

So, you're on a hill and thanks to a software bug your car starts rolling backwards. Your software controlled brakes don't work so how do you stop your car?

[tom66]

I was all set to buy one of these based on the numbers Tesla and Musk gave, but it turned out they were bullshit and the real price is 4x as much. Needless to say I'm very disappointed.

They said it would cost $49,900 after incentives in the US. About $57,400  before. (For the 40kWh pack, or about 130 miles real world range)
It starts from $71,000 for the 60kWh pack, they axed the 40kWh model. Not as bad as 4x, but yeah, they missed their target by quite a bit. Less than 1% of their cars were shipped with 40kWh packs.

I just hope they can maintain the promised $35k for 200 mile car. I know that'll mean it will start from about £30,000 in the UK, but that puts it well into the range of many competitors. Hopefully, they also offer 300 miles range option.

After watching the review there is only one thing I do not like on the car, the lack of a manual handbrake (a.k.a. Parking Brake). Most cars have dual circuit brakes plus the handbrake connected to the rear brakes via a cable that needs tightening now and again, but with the Tesla that ability has been removed.

So, you're on a hill and thanks to a software bug your car starts rolling backwards. Your software controlled brakes don't work so how do you stop your car?

It does have a separate parking brake. It is electronically servoactuated. It is a completely independent system to the ordinary braking system which is hydraulic with a vacuum pump. Even with a complete 12V system failure, you could still apply hyraudlic brakes. The vacuum pump system is good for about 30 seconds of controlled full power braking after power failure. This function is identical to a petrol engine, except the vacuum pump is driven electronically rather than by the accessory belt.

The regen braking would obviously not work, but there are friction brakes for a reason.

[free_electron]

After watching the review there is only one thing I do not like on the car, the lack of a manual handbrake (a.k.a. Parking Brake). Most cars have dual circuit brakes plus the handbrake connected to the rear brakes via a cable that needs tightening now and again, but with the Tesla that ability has been removed.

So, you're on a hill and thanks to a software bug your car starts rolling backwards. Your software controlled brakes don't work so how do you stop your car?

Ehm. No. The normal brake pedal is a hydraulic brake system delivered by Brembo (german engineering) not electrically controlled ( the hydraulic pump is electric) . Hillhold is not done using the motor as it burns too much power in one winding to hold the car on an incline. The hillhold function uses the gyroscope of the car to detect i cline and activates the parking brake.

Here is how the systems work
- hydraulic brake : closed loop system using electric pump to create pressure for the servo.
- electric brake : two additional brake calipers on the rear wheels that are driven by an electric worm drive and are either open or closed.
- regeneration : slow down the car by using the kinetic energy of the car to use the motor as generator and dumping that i to a load (the battery)

Normal driving : take your foot off the drive pedal and regeneration kicks in. Regeneration is not all on or all off. It is proportional to your foot movement. It is like a gas engine. Take foot of pedal a ti y bit and car slows a tiny bit. Take it completely off and you get full effect. (Except here the full effect is much more pronounced than with a gas engine)

Last few feet , or on an incline : press standard hydraulic brake just like with regular car.

If on an incline (hill) the positional system of the car (this thing has gyroscopes) detects an incline it also activates the mechanical parking brake. So, when you release the hydraulic brake pedal the car does not roll backward or forward. The parking brake stays on for one second then disengages. If you touch the accelerator the parking brake disengages immediately.

If, during driving you need the parking brake simply press and hold the 'park' button on the (forward/reverse/park comtrol handle.

When done driving you click the car in 'park' to turn it off. This engages the mechanical parking brake as well.

[free_electron]

-the odb does not allow you access to the real can busses. They have a dedicated can bus only serving odb. Data is filtered. You have no access to the internal systems.

Can one access the OBD with a standard car OBD-II connector and software?

Yes. It is a nomal odb but a dedicated bus.
This car has multiple can (and lin and flexray) busses. There is no direct connection to those through odb.
The odb port is a dedicated lane that allows you to read certain data that they allow you to read.
You probably can read speed, acceleration, throttle position, the usual stuff that would be needed for aftermarket black boxes or other gizmos.
You will not have access to the control data for , lets say the battery charger. You can probably read the state, but anything you try to send in would not go through to the internal busses. It is a filtered port. You only get to see what they let you see. In a sense you are reading data from a buffer somewhere in the main computer. That buffer is read only and filtered.

[max_torque]

I'm wondering how long it will be before legislation is necessary to prevent in-car systems becoming too distracting to the driver??

Also, Dave,  try and drive with two hands equally balanced on the handwheel!!  (people who drive by steering using one hand on the top of the wheel are awful drivers......... ;-)

[zapta]

But it's my ***ing car - I'll plug whatever in want!

Warranty void . You do not want to lose your 8 year end to end warranty with unlimited miles...
Tampering is detected and cause for voiding warranty.

In the US a warranty can be voided arbitrarily. It's part of the Magnuson-Moss act.

On the other hand, the few Tesla people I know are big-brother-knows-better-and-will-protect-us-from-ourselves types so I don't think this practice will bother them.

[Alexei.Polkhanov]

City of Vancouver installed two parking spots with charging stations in front of my building. I see one or two Teslas parked there every morning when I drive to work. Someone convinced me to take it for a test drive few months ago - I did not like it. Interior and dash board are ugly contraption all together IMHO. I don't see any use of that big ugly flat panel that they installed there.

One of the guys that hangout at local hacker/maker club own Tesla and he said they hacked it all way almost completely. I noticed LCD panel was missing in his car (was just a hole instead) and if I understood correctly they are trying to strip it down to bare minimum leaving only the parts that required for car to work essentially. They have shown pretty big pile of "useless" stuff in their garage that they stripped off the car already. I hope that effort will result in some cool after-market gadgetry, hacks, mods of all sorts  Well I guess it depends on how popular it will be. If I am to buy one there is no way I will let someone to connect to MY CAR.

[Towger]

I'm wondering how long it will be before legislation is necessary to prevent in-car systems becoming too distracting to the driver??

It already exists here and was the first thing I thought of when the yank was messing with the center console, while Dave was driving. From what I have seen of advanced systems here, they go blank or display the text 'Driving...' while moving and come back to life when stationary.

[mikeselectricstuff]

IMO a touchscreen is a really lousy UI for a car.
You need real knobs & buttons that you can feel without looking. Voice also seems like a good option if it can be made to work reliably.
 
 

[EEVblog]

IMO a touchscreen is a really lousy UI for a car.
You need real knobs & buttons that you can feel without looking. Voice also seems like a good option if it can be made to work reliably.

I won't disagree, but in this case most (all?) of the really useful stuff is on the buttons on the steering wheel and the instrument cluster displays.
You wouldn't touch the main screen while driving.

[Lightages]

As a tech geek and a motor head, this is really cool. I love it and the whole look of it. But, and it is a big but.....

It is a total waste of money, time, and technology with the world's current balance of power generation. Until we shut off all the fossil fuel generation, idiotic food crop produced fuel replacements, and pie in the sky wind generation failures, the electric car is a bigger polluter and waste of resources than the majority of fossil fuel burning vehicles. All this technological research money needs to moved to fusion research and other nuclear power generation before we think of more ways to use more electricity.

Elon....are you listening? Stop wasting your talent on consumer end use products and get on to the infrastructure!