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>One person familiar with the talks said that Waymo wanted Honda to supply electric vehicles -- an area where the automaker is just beginning to establish itsel

>One person familiar with the talks said that Waymo wanted Honda to supply electric vehicles -- an area where the automaker is just beginning to establish itself. All of Waymo’s existing partnerships supply EVs or plug-in hybrids because its autonomous driving system needs more power than the puny 12-volt batteries in conventional cars. I hope they realize that there is an alternator generating power.

bluGill 8y ago
What is startup time? People get into their car, start the engine, buckle their seat belt, put the car in gear and go - from the time the engine is running until the car is moving is < 5 seconds. In some cases the alternator is setup to not start charging for 1 minute (so the engine doesn't see as much load until it has warmed a little). Waymo gets 5 seconds to start moving from the time someone gets in the seat - this includes time to programs the route (you have don't need the full destination, until you get out of the garage). Most computers need longer than this to start. However if you have good batteries you can cheat - go to warm shutdown and keep memory active even when the car is off for example.
bryanlarsen 8y ago
But 12V alternators are less efficient than the 48-Volt starter/generators used in modern "mild hybrids". Volvo, Volkswagen, Mercedes-Benz and PSA plan on introducing these in every new model moving forward, so that doesn't seem like much of an ask from Waymo.
- kalleboo 8y ago
  Honda also has a bunch of mild hybrids though. First one I pulled up on Wikipedia from 2012 apparently does 144 volt.
deleted 8y ago
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danans 8y ago
> I hope they realize that there is an alternator generating power The power output of an alternator is a function of the engine RPM, so it can't be relied on to provide consistent power, even when the engine isn't running, as needed by autonomous driving systems. You need a sufficiently specced battery (capacity, power output,etc) in between the ultimate power source (alternator, grid) and the autonomous system, something that EVs and PHEVs provide by default. Most electrical functions in a car (radio, windows, fans) are designed to operate within the power output of the battery, not the maximum output of the alternator. The functions that can't fit within that capacity (i.e A/C compressor) are mechanically coupled to the engine output, and therefore shut off when the engine shuts off. EDIT: wording
- dsfyu404ed 8y ago
  If you're choosing a car to build into a self driving test fleet electrical capacity is a really low priority because it's so easy to fix yourself if need be. There's nothing preventing Waymo from bolting a group 31 (big, cheap battery sized used in commercial trucks) down beside whatever over-engineered enclosure holds your self driving computer.
  - danans 8y ago
    Waymo presumably already has ways of modifying vehicles used for autonomous driving tech development, perhaps with big cheap batteries. But for a self driving taxi service fleet, you wouldn't want your customers rolling around in vehicles with a big cheap truck battery bolted inside it. You need a battery that is well integrated into the vehicle, for safety and to optimize the customer experience.

bluGill 8y ago

What is startup time? People get into their car, start the engine, buckle their seat belt, put the car in gear and go - from the time the engine is running until the car is moving is < 5 seconds. In some cases the alternator is setup to not start charging for 1 minute (so the engine doesn't see as much load until it has warmed a little). Waymo gets 5 seconds to start moving from the time someone gets in the seat - this includes time to programs the route (you have don't need the full destination, until you get out of the garage). Most computers need longer than this to start. However if you have good batteries you can cheat - go to warm shutdown and keep memory active even when the car is off for example.

bryanlarsen 8y ago

But 12V alternators are less efficient than the 48-Volt starter/generators used in modern "mild hybrids". Volvo, Volkswagen, Mercedes-Benz and PSA plan on introducing these in every new model moving forward, so that doesn't seem like much of an ask from Waymo.

kalleboo 8y ago
Honda also has a bunch of mild hybrids though. First one I pulled up on Wikipedia from 2012 apparently does 144 volt.

deleted 8y ago

[deleted]

danans 8y ago

> I hope they realize that there is an alternator generating power The power output of an alternator is a function of the engine RPM, so it can't be relied on to provide consistent power, even when the engine isn't running, as needed by autonomous driving systems. You need a sufficiently specced battery (capacity, power output,etc) in between the ultimate power source (alternator, grid) and the autonomous system, something that EVs and PHEVs provide by default. Most electrical functions in a car (radio, windows, fans) are designed to operate within the power output of the battery, not the maximum output of the alternator. The functions that can't fit within that capacity (i.e A/C compressor) are mechanically coupled to the engine output, and therefore shut off when the engine shuts off. EDIT: wording

dsfyu404ed 8y ago
If you're choosing a car to build into a self driving test fleet electrical capacity is a really low priority because it's so easy to fix yourself if need be. There's nothing preventing Waymo from bolting a group 31 (big, cheap battery sized used in commercial trucks) down beside whatever over-engineered enclosure holds your self driving computer.
- danans 8y ago
  Waymo presumably already has ways of modifying vehicles used for autonomous driving tech development, perhaps with big cheap batteries. But for a self driving taxi service fleet, you wouldn't want your customers rolling around in vehicles with a big cheap truck battery bolted inside it. You need a battery that is well integrated into the vehicle, for safety and to optimize the customer experience.