I really need these ....
- Thread starter M00ka
- Start date
Uhuh,
The whole thing is a can of worms TBH.
I'm sure we're all aware that the SRV handles like it's auditioning for a role in a "Fast & Furious" film whenever you try to make a turn on level ground.
That would seem to suggest a fundamental lack of mechanical grip, possibly magnified as a result of low gravity (although it happens on high g worlds too).
And yet, on side-slopes, it sticks to the surface like it was bitten by a radioactive spider.
And then there's the issue of CoG.
That pic' I posted was taken on something like a 70° side-slope.
Somehow, the SRV isn't rolling sideways down the hill, which would suggest it's CoG is somewhere down between it's wheels.
Now, that might actually be possible, if we assume that the thrusters in the wheels are heavy and the rest of the SRV is super-lightweight.
The only problem is, that magnifies the question of why those super-heavy wheels don't slide on a side-slope.
I suppose some of this might be explained away by suggesting the wheel-thrusters are actively pressing the wheels into the surface and/or helping prevent sliding.
If that's the case, though, you have to wonder why the same system makes such a lousy job of preventing spins on flat ground.
Don't get me wrong, I enjoy buzzing around in the SRV and I think FDev have made a good job of the overall "feel" of it... but it makes no sense at all.
The weight is on the front axles I believe, or at least, it should be. I build RC crawlers which are capable of climbing a 1 in 8 incline (approx 80 degrees straight up), and can get over ANYTHING they can straddle with the wheelbase, although we have control over the speed of each axle independently, so we even use the squidginess of tyres to 'grab' rock features for an advantage (we can even climb NEGATIVE inclines using this trick if the circumstances and approach are just right), it's a very advanced sport, I digress, point is the back end is so loose because it has almost no weight compared to the front, because climbing. we actually glue lead to the front axle of these things (see the image below, that is the battery, that yellow thing sticking up on the front axle, any weight we can put there, gets put there).Uhuh,
The whole thing is a can of worms TBH.
I'm sure we're all aware that the SRV handles like it's auditioning for a role in a "Fast & Furious" film whenever you try to make a turn on level ground.
That would seem to suggest a fundamental lack of mechanical grip, possibly magnified as a result of low gravity (although it happens on high g worlds too).
And yet, on side-slopes, it sticks to the surface like it was bitten by a radioactive spider.
And then there's the issue of CoG.
That pic' I posted was taken on something like a 70° side-slope.
Somehow, the SRV isn't rolling sideways down the hill, which would suggest it's CoG is somewhere down between it's wheels.
Now, that might actually be possible, if we assume that the thrusters in the wheels are heavy and the rest of the SRV is super-lightweight.
The only problem is, that magnifies the question of why those super-heavy wheels don't slide on a side-slope.
I suppose some of this might be explained away by suggesting the wheel-thrusters are actively pressing the wheels into the surface and/or helping prevent sliding.
If that's the case, though, you have to wonder why the same system makes such a lousy job of preventing spins on flat ground.
Don't get me wrong, I enjoy buzzing around in the SRV and I think FDev have made a good job of the overall "feel" of it... but it makes no sense at all.
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The weight is on the front axles I believe, or at least, it should be. I build RC crawlers which are capable of climbing a 1 in 8 incline (approx 80 degrees straight up), and can get over ANYTHING they can straddle with the wheelbase, although we have control over the speed of each axle independently, so we even use the squidginess of tyres to 'grab' rock features for an advantage (we can even climb NEGATIVE inclines using this trick if the circumstances and approach are just right), it's a very advanced sport, I digress, point is the back end is so loose because it has almost no weight compared to the front, because climbing. we actually glue lead to the front axle of these things (see the image below, that is the battery, that yellow thing sticking up on the front axle, any weight we can put there, gets put there).
http://car.hoy.co.uk/wp-content/uploads/2016/11/rc4wd-015_thumb.jpg
What happens when you try to traverse a side-slope with that thing?
Nice looking machine though.
I like it when thinks are properly engineered for a given purpose. [up]
What happens when you try to traverse a side-slope with that thing?
Nice looking machine though.
I like it when thinks are properly engineered for a given purpose. [up]
82* side as well. The chassis weighs 115 grams (see the carbon fiber frame and titanium links underneath?), and the axles a kilo each including wheels (wheels often have pendulum weights under them that stay at the bottom as the wheel turns, adding more weight below the axle). Every other part of the vehicle (including what's in the 'cockpit' area) is as low as physics allows, even wires are cut to minimum lengths so no weight is in the wrong place (the owner of the above model could do better in this regard). They are truly amazing machines, as they have no need to compromise for the meat component.
This model above is the very top level of competition grade, about a 14 inch wheelbase and cost about 2000 quid all done including electrics, but you can spend a LOT more. It is not mine, but I have one very similar (same chassis, links and axles). The axles are 'Bully 2' by a company that closed this year called RC4WD (you'll be missed!) The carbon chassis and Ti links could be anything, some people even cut/bend their own.
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So, that's what it would cost us in the store, to get an SRV that works, and has a docking computer.
So, that's what it would cost us in the store, to get an SRV that works, and has a docking computer.
Cheap at the price! I dread to think what a NASA Rover costs!!
Once had a data scan mission that lead me into the wall of a huge crater. Nothing but ridges and slopes everywhere. Took me the better part of an hour to find a landing spot, climb over to mountains, scan the data point and get back again but I made it. Something with more climbing power would have been appreciated.
