Model Y review from an mechanical and software engineer's standpoint.

[Quickst]

Of course.

Ok, but you stated previously:

I guess you must have forgotten this Landcruiser 200 ICE vehicle or has it been modified to be powered by something other than a ICE when you stated this previously?

"Muscle memory" I have found plays a big part in this behaviour I think. Or IMO to overcome this "muscle memory" you have to regularly think to yourself as I try to do, something along the lines of "Remember it's on the other side."

Geez, I have to admit I have never heard the term "negative forward motion" before. Did you make this term "negative forward motion" up?

Actually I won't finish the reply to your statement above and the rest of your full statement to me until I know the answer to this.

The LC200 is in the family but not in my garage. Not in frequent use - maybe twice a year.
Muscle memory?.
Sure, but as I said I don't have an issue swopping from LH indicators to RH indicators. Of course YMMV

Negative forward motion?.
Remember electric motors have no physical linkage to the wheels. The connection is via an electromagnetic force.

In this way an electric motor causes acceleration in one direction or the opposite direction by reversing the polarity of the electric current. This can occur instantaneously. A regen braking is basically the motor inducing an electric current in an opposite direction - effectively acceleration in reverse.

Negative forward motion is just another way of indicating direction. But what I should have said was "negative acceleration"

 

[paulp]

The LC200 is in the family but not in my garage. Not in frequent use - maybe twice a year.
Muscle memory?.
Sure, but as I said I don't have an issue swopping from LH indicators to RH indicators. Of course YMMV

Negative forward motion?.
Remember electric motors have no physical linkage to the wheels. The connection is via an electromagnetic force.

In this way an electric motor causes acceleration in one direction or the opposite direction by reversing the polarity of the electric current. This can occur instantaneously. A regen braking is basically the motor inducing an electric current in an opposite direction - effectively acceleration in reverse.

Negative forward motion is just another way of indicating direction. But what I should have said was "negative acceleration"

You can accelerate going backward

 

[Quickst]

You can accelerate going backward

Yes and the dealer once did that and smashed the tailgate into a fire hose reel.

 

[TrevRex]

Remember electric motors have no physical linkage to the wheels.

Actually I will try to forget I ever read this misinformation to put it a nicely as I can.

The part of an electric motor called the Rotor (the part that revolves) is physically attached to the wheels via the reduction gears, differential, drive shafts (and joints) and wheel hubs assemblies. The connection between the Stator and the Rotor of an electric motor is via an electromagnetic force and in the case of our permanent magnet electric motors a magnetic force that interacts with that said electromagnetic force.

Negative forward motion is just another way of indicating direction.

Ok if you are now writing about direction of motion I would submit putting negative and forward in the same context as describing a direction of motion is very naïve IMHO. In the Classical Mechanics discipline of physics, which I am trained in for Mechanical Engineering, we use positive/negative in the mathematical quantities of the components of motion like acceleration, velocities etc. Or in just basic terms words like driving forward/reverse etc suffice.

But if we are going to make our own terms up like "negative forward motion" to describe a direction of motion I have dibs on "anti-forward motion".

But what I should have said was "negative acceleration"

Yes you should have or just deceleration or to decelerate if we just want to simplify it would have sufficed I would suggest.

I wonder if the reverse is just a reverse polarity which causes negative forward motion.

Ok now we have sorted out your mistaken terminology and you meant negative acceleration or deceleration in simple terms then yes an applied reverse polarity would apply a force that will cause deceleration.

As I understand it there are no gears which turn in the opposite direction when R is selected.

Actually in engineering terms there are gears that reduce the RPMs (reduction gears) of the electric motor before inputting the differential and yes they would turn in the opposite direction when moving in the reverse direction compared to moving in the forward direction.

Negative forward motion is basically like a regen.

Deceleration using your applied reverse polarity is basically regen. Yes I agree.

So even if R is able to be selected all it would do is slow the vehicle down.

Ok, not only would it slow the vehicle down but if that force continued to be applied it would of course bring the vehicle to a stop and then start to accelerate in the opposite direction of travel. Intension of purpose (I want to reverse), an individuals reflexes, magnitude of that force ie how hard you are pressing on the accelerator could be some of the components that could come into play here I would submit.

 

[paulp]

Ok if you are now writing about direction of motion I would submit putting negative and forward in the same context as describing a direction of motion is very naïve IMHO. In the Classical Mechanics discipline of physics, which I am trained in for Mechanical Engineering, we use positive/negative in the mathematical quantities of the components of motion like acceleration, velocities etc. Or in just basic terms words like driving forward/reverse etc suffice.

You must really struggle with the tesla term “full self driving” then

 

[TrevRex]

You must really struggle with the tesla term “full self driving” then

LOL. Wow, talk about assuming how someone else thinks. Some may call that arrogance but hey I will try to be nice. But in any case you wrong ie I do NOT "really struggle with the tesla term full self driving” and if you had understood what I had written about using basic terms to describe driving which I said "suffice" you would have realized this.

But I will try to help you understand ( because I am such a nice guy) by using some other basic terms that "suffice" ( suffice: meaning meets the needs of ) to describe the motion or driving of a vehicle.

Driving fast/slow, speeding up, slowing down, turning a corner etc etc. All these words or phrases describe with a sufficient vocabulary IMO the motion of a vehicle that I hope most people even without a physics background could understand ie they "suffice".

Now the basic term "full self driving” conveys the meaning to me of what I think Tesla are trying to do but their obsession with it, and probably the sensors they are trying to limit themselves to using, is affecting IMHO the other more basic system like adaptive cruise control/TACC.

 

[paulp]

LOL. Wow, talk about assuming how someone else thinks. Some may call that arrogance but hey I will try to be nice. But in any case you wrong ie I do NOT "really struggle with the tesla term full self driving” and if you had understood what I had written about using basic terms to describe driving which I said "suffice" you would have realized this.

But I will try to help you understand ( because I am such a nice guy) by using some other basic terms that "suffice" ( suffice: meaning meets the needs of ) to describe the motion or driving of a vehicle.

Driving fast/slow, speeding up, slowing down, turning a corner etc etc. All these words or phrases describe with a sufficient vocabulary IMO the motion of a vehicle that I hope most people even without a physics background could understand ie they "suffice".

Now the basic term "full self driving” conveys the meaning to me of what I think Tesla are trying to do but their obsession with it, and probably the sensors they are trying to limit themselves to using, is affecting IMHO the other more basic system like adaptive cruise control/TACC.

I missed the smiley emoji on my comment. It wasn’t meant to be serious

 

[TrevRex]

I missed the smiley emoji on my comment. It wasn’t meant to be serious

No problem. I was taught at a young age, by someone that had my deepest respect, to accept these moments in our lives where things don't work out the way we planned through mistakes, tragedy, unforeseen circumstances, accidents etc to try and look at it in a positive way because it is "character building" and it will help shape our lives and persona now and into the future.

Ok. So I am set for life and will be able to handle anything because any bad stuff that happens is "character building". Sounds like a noble philosophy to me.

But the older I get I think geez I am sick of of all this supposedly "character building" that happens to me.

 

[OzVic]

Since we're talking about neutral and stuff... can any engineers explain what happens to the power generated by the rear permanent magnet motor when rolling in neutral? I've noticed my Tesla Model 3 rolls 'really well'. Is the power generated just dumped somewhere (heat)? Or actually put into the forward/backward motion of the vehicle?

 

[cafz]

Since we're talking about neutral and stuff... can any engineers explain what happens to the power generated by the rear permanent magnet motor when rolling in neutral?

My understanding is that it operates the motor in a zero-torque regime, so it produces no power (and only consumes a little in the field windings).

 

[TrevRex]

Since we're talking about neutral and stuff... can any engineers explain what happens to the power generated by the rear permanent magnet motor when rolling in neutral? I've noticed my Tesla Model 3 rolls 'really well'. Is the power generated just dumped somewhere (heat)? Or actually put into the forward/backward motion of the vehicle?

Yea like cafz says it is usually only taking just enough power out of the battery to overcome the resistance of the motor to rotate when no power is supplied.

All the permanent magnet motors I deal with and can get to actually turn the Rotor with my own hands or with tools, have a noticeable resistance to rotate and also have a noticeable "cogging" torque like it has detents. Now that "cogging" when running permanent magnet motors at slow speed make them run rough or in a jerky manner so manufacturers for certain application like EVs need to go to extra trouble to try to reduce it. Hope you understand.

 

[TrevRex]

Ok, like I said before in this thread I had sold my Model Y RWD and was waiting for a Model Y LR I had ordered in April ( same day after orders opened for LR here in Australia).

Picked up the Model Y LR yesterday from Chatswood and drove it back to the Mid North Coast on the same day.

My impressions so far compared to my Model Y RWD:

1. Suspension is noticeable more comfortable with the LR over bad sections of road IMO and after my family, wife and 2 sons, drove it when I returned they also agreed.

2. Uses slightly more energy ie up from approx 155 Wh/km RWD at highway speeds to 170 Wh/km LR but the bigger battery and the usability of AWD for us of the LR more than makes up for this I think .

3. Extra power is very noticeable IMO.

4. Had no problems with adaptive cruise control/TACC on the approx 4 hrs I drove it yesterday to bring the LR back home. Only time I saw a noticeable slow down event on the whole trip was when a truck crossed into my lane partly for no apparent reason while I was overtaking. Might not have liked Teslas LOL but a quick override with the accelerator against the slowdown left the truck disappearing into the distance in the rear view mirror. I think in this circumstance it was totally acceptable behaviour by TACC.

All in all the TACC with phantom braking has been my biggest "gripe" with my RWD for my family and I. Anecdotally, just for this trip, it seemed to me to be a far better experience with the LR I think. But more testing in different light conditions etc is probably warranted before I draw any conclusion.

5. A parcel shelf, I think Tesla calls it, is now included which I think seems to make the interior quieter especially over rougher roads from my initial impression. Extra sound deadening is probably showing up here I think. But this is just my initial impression and it could be just the "vibe" as they say for me to notice this.

6. The external speaker makes a what I will call a "spacey" noise outside the cabin while reversing that my RWD never had. Yes, Boombox as an app is also now included.

This is just a quick review I think. I want to start setting up my Scan My Tesla OBD plug, for the drive battery and power analysis etc, that I had removed from my RWD before I sold it. I also want to get the LR out amongst some good winding local roads for handling tests at speed that I always test my vehicles on before comparing the AWD/RWD differences here.

But some here may find this early impression interesting.

 

[paulp]

Ok, like I said before in this thread I had sold my Model Y RWD and was waiting for a Model Y LR I had ordered in April ( same day after orders opened for LR here in Australia).

Picked up the Model Y LR yesterday from Chatswood and drove it back to the Mid North Coast on the same day.

My impressions so far compared to my Model Y RWD:

1. Suspension is noticeable more comfortable with the LR over bad sections of road IMO and after my family, wife and 2 sons, drove it when I returned they also agreed.

2. Uses slightly more energy ie up from approx 155 Wh/km RWD at highway speeds to 170 Wh/km LR but the bigger battery and the usability of AWD for us of the LR more than makes up for this I think .

3. Extra power is very noticeable IMO.

4. Had no problems with adaptive cruise control/TACC on the approx 4 hrs I drove it yesterday to bring the LR back home. Only time I saw a noticeable slow down event on the whole trip was when a truck crossed into my lane partly for no apparent reason while I was overtaking. Might not have liked Teslas LOL but a quick override with the accelerator against the slowdown left the truck disappearing into the distance in the rear view mirror. I think in this circumstance it was totally acceptable behaviour by TACC I think.

All in all the TACC with phantom braking has been my biggest "gripe" with my RWD for my family and I. Anecdotally, just for this trip, it seemed to me to be a far better experience with the LR I think. But more testing in different light conditions etc is probably warranted before I draw any conclusion.

5. A parcel shelf, I think Tesla calls it, is now included which I think seems to make the interior quieter especially over rougher roads from my initial impression. Extra sound deadening is probably showing up here I think. But this is just my initial impression and it could be just the "vibe" as they say for me to notice this.

6. The external speaker makes a what I will call a "spacey" noise outside the cabin while reversing that my RWD never had. Yes, Boombox as an app is also now included.

This is just a quick review I think. I want to start setting up my Scan My Tesla OBD plug, for the drive battery and power analysis etc, that I had removed from my RWD before I sold it. I also want to get the LR out amongst some good winding local roads for handling tests at speed that I always test my vehicles on before comparing the AWD/RWD differences here.

But some here may find this early impression interesting.

Is the hardware that drives the cruise control the same in both cars?

 

[TrevRex]

Is the hardware that drives the cruise control the same in both cars?

G'day paulp. Sorry I didn't back to you earlier. Been busy at work especially after sacking myself to go down to pick up the new car.

You mean do I now get HW4 on my new Model Y LR? No I think it's same hardware as the previous MY RWD. But I will check more carefully with images I have seen in articles etc when I get the chance. Getting the car I bought off others in my family is not easy at the moment. Me, I will have to probably work most of the weekend to help pay it off.

But seriously, I am glad my wife and two young adult sons seem to be really enjoying driving it as much as I did.

 

[TrevRex]

Thought some may be interested in a acceleration run we did with the MY LR. Note the Creep mode showing (top left) which my eldest son prefers who was driving while I took the screenshot. I myself prefer Hold mode (one pedal). Also note max discharge bottom right 357 kW compared to 287 kW showing on left middle. 357 kW was from a earlier run.

 

[Quickst]

Also note max discharge bottom right 357 kW compared to 287 kW showing on left middle

I wonder how kW in eV compares to kW in ICE. One is Volts x Amps and the other is torque x rpm x 9.5
If 287 kW or 357kW can be delivered to motors, how would it convert to kW in terms of torque x rpm x 9.5

Thought some may be interested

Do you have inverter temps?

Also when does front motor activate?

 

[paulp]

G'day paulp. Sorry I didn't back to you earlier. Been busy at work especially after sacking myself to go down to pick up the new car.

You mean do I now get HW4 on my new Model Y LR? No I think it's same hardware as the previous MY RWD. But I will check more carefully with images I have seen in articles etc when I get the chance. Getting the car I bought off others in my family is not easy at the moment. Me, I will have to probably work most of the weekend to help pay it off.

But seriously, I am glad my wife and two young adult sons seem to be really enjoying driving it as much as I did.

If the hardware is the same, and the software is the same, I wonder how the performance can be different?

 

[cafz]

I wonder how kW in eV compares to kW in ICE. One is Volts x Amps and the other is torque x rpm x 9.5
If 287 kW or 357kW can be delivered to motors, how would it convert to kW in terms of torque x rpm x 9.5

It's the same, minus the fraction that ends up as heat in the motors (less than 5% for the Tesla motors, apparently).

 

[Quickst]

It's the same

If its the same, then the power on the wheels is still insane compared to most ICE

 

[cafz]

If its the same, then the power on the wheels is still insane compared to most ICE

It sure is.