Thank you "Lucasb7" for posting the web site for that great info and illustrations. Remarkable how the system functions. On the towing (or pushing) capacity in reverse, the engineers and physics folks need to create a basic chart/table showing the capacity to move a trailer in reverse at various inclines and weights of the trailer. I assume that reverse will work on level ground where a 3500 lb. trailer can be moved. But, what are the limits to moving a trailer (various weights) at different inclines (degrees). This is definitely a factor for some folks that expect to tow a trailer and need to use reverse on occasion (on various inclines). I only use my hitch as a bicycle carrier, but I would be very dissapointed if I purchased this to tow a boat or trailer.

 

Thanks for clearing up my confusion about MG1 and MG2, MG3 (traction motors).

How can this simulation be replicated in real life. I haven't been able to get this sort of speed out of MG2. I suppose it does it momentarily and not sustained.



Thanks too for clarifying power and speed in reverse. Interesting effect on towing.

 

In all likelihood you have gotten that situation to occur. MG2 is the only part of the planetary gearbox that has a fixed relationship to the speed of the wheels. If you spend more time with the diagram you'll see that MG2 is the only motor that changes vehicle speed. So if you're going 60, MG2 will be turning at ~3500 RPM no matter what. If the car needs more power it will up the ICE's RPMs which also raises MG1's RPMs accordingly.

Keep in mind that the "power gauge" has very little correlation to the speed of any of these motors/engine. It is more a summation of how many kW's the car thinks it is putting down with combined output from MG2 and the ICE. Prius owners often use a ScanGauge to determine engine RPM but I don't think it displays the speed of the motors. It will display the amount of energy being fed to the motors though.

At top speed, MG2 and the ICE will both be spinning at their respective redlines.

 

Interesting problem. Definately a major flaw. I would like to see a smaller ICE and more powerful electric motors in the RX's future, of course made possible by Li-Ion batteries. That would certainly help with this problem, but perhaps not remedy it.

 

I haven't found any downside to owning an RX. I have been an owner since 2008 and we pull our boat everywhere. Sounds very unusual that the front of your vehicle would be down by the water and you are backing your boat up the ramp. Sounds like this once a year pull should possibly be handled by a heavy duty truck and not a luxury SUV.

 

At the risk of insulting anyone's intelligence; and with apologies in advance should hat occur; and with an assumption that a trailer with a capacity of 3,500# will have trailer brakes; and in the further assumption that said trailer brakes are surge/hydraulic (and here comes the risk of insult) does the brake have a "backup" setting - in which the surge brake is locked off so that the tow vehicle isn't pushing/backing the trailer up a steep incline with the trailer's brakes applied?

My trailer has one; and I've been known to forget to throw the lever - fortunately my drive is short, and the incline moderate.