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Comment by r00fus | Hacker News Reader

For those who are interested in specs of the I-PACE, I had to do a bit of seperate searching [1] for those. Hopefully the specs are somewhat similar. 300mi range isn't too shabby and it looks decent.

"As standard the car comes with a 90kWH battery pack which produces a total system output of 400PS and 696 NM.

It is powered by two electric motors which produce 200PS and 348Nm each and are mounted to both the front and rear axles, enabling four-wheel drive.

Due to the instant torque of an electric powertrain the car will be able to sprint from 0-60mph in just 4.5 seconds and on to a top speed of 124 mph.

The car will be able to travel up to 298 miles of range on a single charge."

[1] https://www.express.co.uk/life-style/cars/937715/Jaguar-Waym...

(edit: link)

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I'm actually curious to see what the difference in mileage is between human drivers and AI drivers. I'm assuming they can optimize breaking and acceleration to be more power efficient. I remember hearing that in terms of wear & tear, Waymo cars actually get far less of it compared to human drivers.

I'd say the cars will be able to hyper-mile, utilizing regenerative braking as much as possible and actual brake pads as little as possible.

Will they avoid potholes? In New England, we have MANY bad potholes, I wonder what they will do about that. Will they avoid manhole covers, objects on the road? I personally can't wait to see when/how it all plays out.

What I find odd is how does a car with 400PS and almost 700NM of torque max out at 124mph? In comparison a Jaguar F-Pace 3.0, which has 375PS and 430NM torque will max out at (limited) top speed of 155MPH.

The iPace weights just 300KG more than the F-Pace, so it’s not down to extra weight alone.

Gearing. 99.9% of driving happens below 100kph, so you optimize for that. You start reaching the mechanical and electrical limits if you spin up the motors that fast. You could certainly get a lot faster, but you'd lose out on low-end torque. Either that or you put a gearbox in, but that adds complexity + weight.

Does a P100D have a gearbox? I thought it was single speed. It also has a mountain of torque and power.

I believe it's a single gear. There are differentials for the axles, but no mention of gearing for the motor itself: https://en.wikipedia.org/wiki/Tesla_Model_S#Powertrain

I expect freeway driving to represent more than 0.1% of all driving.

There could be a number of things limiting the speed of an electric motor aside from limited torque/mass. The motors could be speed limited because of high material failure rates above a certain threshold or because the circuits can't be driven that fast for whatever reason.

124 mph is 200 kph, corresponding to 'U' speed-rated tires. So its probably about less-expensive long-life tires, rather than a fundamental power limit.

Were you able to determine if the car is capable of being manually driven as well? Or is it self-driving only?

I chuckled a bit trying to imagine a situation where the SDC logic would conclude that it was necessary to floor the accelerator up to 124MPH.

Yes. One thing that will happen is that people will not care anymore about how fast it accelerates but more about how smooth it goes. You don't want to spill that wine glass on you.

The I-PACE is being by Jaguar sold to consumers (at 64k quid a pop, not cheap) so the answer must be yes, manually driven. It's in the article.

> not cheap

Well, if every Tom, Dick and Rajiv thinks it's being driven by a computer and they can cut it off ...

It's a regular ('manually driven') consumer vehicle being produced by Jaguar Land Rover - it has been adapted by Waymo for self driving.

https://www.jaguar.co.uk/jaguar-range/i-pace/index.html

A new meaning to "manual or automatic"!

The photos seem to show quite clearly a steering wheel and wing mirrors...

I'd guess these cars are being designed to have the self driving system as an addon that can be removed/redesigned in the future as the tech evolves.

Note the 300 mile range will be NEDC given the British source, which probably makes it somewhat optimistic.

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