MrBill400x

I can press the brake and gas simultaneously, but it appears no charging is going un. Seems charging only happens when i am braking. Anyone?

ukrkoz

Be advised, that there is not direct connection between brakes and brake pedal and engine and accelerator pedal. You have a drive by wire vehicle. Hence, it's all decided by ECM. Out of curiosity, you can try revving vehicle in Park. It'll rev few times then ICE will shut down and no matter what you do to gas pedal, engine will not respond.
Not sure why you are experimenting with this. But it's fun to do anyway.

MrBill400x

So if I am stopped, in drive, foot on the brake, and press the gas pedal, the instrumentation does not indicate the battery is charging, even if the hybrid battery is not fully charged.

ukrkoz

Yes. Like I said, you have no control over it. especially with brake pedal depressed.
Pay attention to 2:15. What happens when vehicle stops. System does not operate.

thomas1

There is no alternator, the 12 volt battery is charged through the hybrid battery which is charged from the motor/generators

riredale

The gas pedal is "drive by wire" but the brake pedal is most definitely a mechanical connection. If everything goes kablooey (a technical term) then your gas pedal won't do anything anymore but you can still stomp on the brakes to come to a stop.

I don't think of my 2010 RX450h as an electric vehicle but rather as a vehicle powered by an ICE that is computer-controlled to shut down at those times when it would be running inefficiently. During those intervals some electric motors take on the task of moving the vehicle. The battery pack is there to (a) quickly and effortlessly spin up the ICE as needed via a powerful "starter motor," typically dozens or hundreds of times even on a local trip to the market; (b) run all the formerly-engine-driven accessories such as power steering and A/C so that the ICE can be shut down at will; (c) absorb for re-use some of the kinetic energy when braking; and (d) push the vehicle along during those times when the ICE would be forced to operate in an inefficient mode. All energy in the system comes from gasoline, none from a wall outlet. Even so, a hybrid design can get 30-50% better overall fuel mileage doing these things. And no range anxiety.

ukrkoz

I'd suggest to actually go and check if brake pedal is mechanical or not. Maybe on very early RX models. Not on later.

NateJG

[QUOTE=riredale;10022807]The gas pedal is "drive by wire" but the brake pedal is most definitely a mechanical connection. If everything goes kablooey (a technical term) then your gas pedal won't do anything anymore but you can still stomp on the brakes to come to a stop.

https://en.wikipedia.org/wiki/Electr...ntrolled_brake

Electronically Controlled Brakes (ECB)
All Lexus vehicles use Electronically Controlled Brakes (ECB), a ‘brake-by-wire’ system that translates brake pedal pressure into electric signals that, via computer control, help provide precise and optimized braking in virtually any traction condition. Electronic control provides quick brake response when needed, aiding in anticipating and helping correct slides before they might occur. The ECB system is backed by conventional hydraulic brake control in case of the unlikely event of electronic failure. ECB-R is an development of the system that also controls the level of regenerative braking provided by the Lexus Hybrid Drive system.
http://blog.lexus.co.uk/lexus-car-sa...-technologies/

riredale

Fair enough; the automotive press calls the Toyota hybrid brakes "brake by wire."

I was relying on my understanding of what "fly by wire" means in the aviation business. An Airbus joystick has no cable connection to the ailerons or elevator, but rather simply sends signals to a collection of computers that, in turn, decide what to actuate.

The Toyota accelerator pedal is exactly like this--there is no rod linkage or push-pull cable between the pedal and the throttle body. It's all electrical. By contrast, the Toyota steering system has a mechanical link and the Toyota brakes have a mechanical link (though aided by significant computer smarts). If we remove the computers from the car, the steering and brakes will still work. The accelerator pedal won't. But perhaps I'm splitting hairs.

In any event, I think these are brilliant designs.