What is Robby building?

green787

Well-Known Member
Why have the transmission? Seems unnecessary.
Park and a normal reverse, also keeps motors in torque range.... 2 speed.... Otherwise you will need all the reversing contactors, plus in reverse the motors run at half speed from the controller, which means you could do 60mph in reverse.... by gearing it down for reverse it makes it safer when backing up.... more like what we are used to driving, instead of a golf cart which will go at half of it's top speed in reverse.....
 
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green787

Well-Known Member
A common problem with electric cars is "lurching" in reverse.... Novice drivers of golf carts or other electric vehicles tend to give it too much throttle in reverse..... this causes the the novice driver to mash even harder on the gas pedal because of the momentum of the lead foot.... dangerous in a crowd....
Just the opposite of how a novice motorcycle ryder's momentum tends to twist the throttle even further, until they are "supermanning" the bike and it wheelies out from under them, and then they don't want to try it again....
 

jon coleman

Well-Known Member
i did that once^( yeah right), at the gfi winter series, there were these nasty 3 ft roller woops at perris, hit first one, slapped off seat, hanging onto handle bars wfo throttle for next one, luckily i knew to LET the i failed mx school not go of bars and hope bike doesnt leave race track property, it didnt .lucked out
 

RGFan

Well-Known Member
is anyone actually developing electric hybrid off road racing technology ? asking for a friend...

Not a hybrid, but electric....There is a video at the bottom of the article
 

jon coleman

Well-Known Member
soooo this e off roader is gonna compete in parts of the world" damaged by climate change", oh great , tear up the land some more thats allready " damaged"
 

Jacob7672

Nimrod de Ashcraft
It's all about the sprung to unsprung weight ratio. Keep it the same as a TT and you will be golden.
This is not completely true IMO. There is more to it than that. Even if you keep the ratio the same and have the same geometry, the heavier car will always feel more stable if they are both properly tuned.
 

cynicwanderer

Well-Known Member
hybrid, eng could also run a generator too for direct drive elec.motors
actually gas-electric hybrid is a good solution. it allows you to decouple the motor from the drive train, and with inverters (i.e. that change the frequency of the power generated to the variable frequency needed in the drive motor at different speeds) you may not need a transmission. the gas motor runs at best efficiency (constant speed) to drive the generator and there should be some fuel savings.

if you plan to do AWD it's a good way to mechanically decouple the front and rear drive train and you can implement smart traction control between front and back. you could still run standard drivetrains with CVs and differentials, except the transfer case could go away. gas/diesel hybrid is all very old tech and used in a variety of applications, like locomotives, big dump trucks and many ships.

battery power electric vehicles (i.e. non-hybrids) would be impractical for long distance off road racing to be competitive. you might have a all electric class to race evehicles within you class, which I'm sure would gain some traction. however, you'd need to implement some kind of battery swap technology or very high speed charging. battery technology is slowly getting better, but will probably never achieve the energy density of fossil fuels or hydrogen.

however, adding a small battery/capacitor as a momentum recovery device would have several benefits in off road racing, because of the herky/jerky driving we do. it would greatly reduce the fuel consumption because of the regenerative braking, much of which would be used when accelerating out of the turns. it adds complexity, but would probably be worth it.

all of the throttle feel/traction control can be implemented to make the driver happy and feel like they are in control. you could even implement a "classic" mode, to make it feel more traditional.

aside from the development effort and cost, one downside the lack of the visceral experience slamming your car through the gears. it could also be harder on the tires, because you could transmit a huge about of torque, when you have traction, on the other hand with traction control you won't be spinning your tires all the time and causing them to heat up more, unless you like to run it in "classic" mode.

disclaimer, I have zero experience with hybrids in off road racing (I race motorcycles), but the engineer in me would love to work on something like this. Ironically, I'm a luddite in my day to day life, and complain about the trackers and tech we are made to run on the bikes and my reluctant dependency on smart phones, etc... I'd also never get a Tesla, just because I know how software works and how easy it is to screw things up with updates and stuff when you plug it in the internet.
 

michael_loomis

Well-Known Member
I'm still waiting for a state-of-art hydraulic drive. Mid-engine with a pump bolted to it and hoses going to the wheels.
Seems rather inefficient. The most “hydraulic” part of a current TH400 setup (and some manuals) is the torque converter and it’s the most power robbing part.
 

michael_loomis

Well-Known Member
actually gas-electric hybrid is a good solution. it allows you to decouple the motor from the drive train, and with inverters (i.e. that change the frequency of the power generated to the variable frequency needed in the drive motor at different speeds) you may not need a transmission. the gas motor runs at best efficiency (constant speed) to drive the generator and there should be some fuel savings.

if you plan to do AWD it's a good way to mechanically decouple the front and rear drive train and you can implement smart traction control between front and back. you could still run standard drivetrains with CVs and differentials, except the transfer case could go away. gas/diesel hybrid is all very old tech and used in a variety of applications, like locomotives, big dump trucks and many ships.

battery power electric vehicles (i.e. non-hybrids) would be impractical for long distance off road racing to be competitive. you might have a all electric class to race evehicles within you class, which I'm sure would gain some traction. however, you'd need to implement some kind of battery swap technology or very high speed charging. battery technology is slowly getting better, but will probably never achieve the energy density of fossil fuels or hydrogen.

however, adding a small battery/capacitor as a momentum recovery device would have several benefits in off road racing, because of the herky/jerky driving we do. it would greatly reduce the fuel consumption because of the regenerative braking, much of which would be used when accelerating out of the turns. it adds complexity, but would probably be worth it.

all of the throttle feel/traction control can be implemented to make the driver happy and feel like they are in control. you could even implement a "classic" mode, to make it feel more traditional.

aside from the development effort and cost, one downside the lack of the visceral experience slamming your car through the gears. it could also be harder on the tires, because you could transmit a huge about of torque, when you have traction, on the other hand with traction control you won't be spinning your tires all the time and causing them to heat up more, unless you like to run it in "classic" mode.

disclaimer, I have zero experience with hybrids in off road racing (I race motorcycles), but the engineer in me would love to work on something like this. Ironically, I'm a luddite in my day to day life, and complain about the trackers and tech we are made to run on the bikes and my reluctant dependency on smart phones, etc... I'd also never get a Tesla, just because I know how software works and how easy it is to screw things up with updates and stuff when you plug it in the internet.
This is what I’ve been saying since the current crop of supercars popped up.

Think about how much energy is being wasted in suspension travel that could be used to charge batteries, that road cars cannot do. Bonus, helps dampen taking heat out of shocks.
 

michael_loomis

Well-Known Member
A common problem with electric cars is "lurching" in reverse.... Novice drivers of golf carts or other electric vehicles tend to give it too much throttle in reverse..... this causes the the novice driver to mash even harder on the gas pedal because of the momentum of the lead foot.... dangerous in a crowd....
Just the opposite of how a novice motorcycle ryder's momentum tends to twist the throttle even further, until they are "supermanning" the bike and it wheelies out from under them, and then they don't want to try it again....
I’m driven a bunch of electric cars and never experienced this lurching.
 

Bricoop

Well-Known Member
I just watched the Lemans documentary on Netflix. The Porsche and Audi both run hybrids, but one is diesel and one is gas. One runs all drive power through a transmission, the other uses strictly electric on the front wheels. Their lap times were very close. Point being, many different successful formulas exist for hybrids.

I do not think we will ever see RG move to a generator type of system. The sound is too important to him.
 

Total Loss

Well-Known Member
A common problem with electric cars is "lurching" in reverse.... Novice drivers of golf carts or other electric vehicles tend to give it too much throttle in reverse.....
Is that what happened to Malcolm Smith? Probably.
 

jon coleman

Well-Known Member
hes building what we out here are hoping for, us peeons live through our hero's exploits, i hope rg builds a game changer that shows up at the first race of the season, That is what me as an offroad junkie lives for, its the only sport that always has somthing F i failed bootcamp school really cool show up at contingency& tech
 
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