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Soda Popinski

Mars Rover type Rocker-Bogie suspension system on rover "Bogie McBogeface"

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The JPL built Mars rovers have all used a "Rocker Bogie" suspension system, which allows all 6 wheels to remain grounded.  Though, I've built this type of thing in Besiege, and even in VR with Fantastic Contraption, I've never made one in KSP.  After installing Infernal Robotics, and having free spinning washers, I realized I finally could.

It's called a Rocker Bogie, because it uses 2 wheel bogies (like on a train), which are connected with rockers.  There pivot points are completely unpowered, with just gravity keeping the 6 wheels on the ground.  My previous Besiege build used a differential gear similar to the one on Spirit and Opportunity to keep the rover body upright.  Without gears, I ended up making a Differential Bar, like what was used in Sojourner and Curiosity.


Here's some quick clips of the thing.

First up is my proof of concept rovering around Kerbal Space Center.

 

Though robust, I could still use bigger wheels.  Hopefully, getting this thing on Mun will help me get more science to further unlock the tech tree.

 

In order to get it to fit a bit better into a 2.5m rocket with the smaller fairings (haven't unlocked 3.75m yet), I opted to use some Infernal Robotics sorcery to make it fit, along with taking advantage of the free spinning rear bogie to stow up unpside down.  I also loaded it with the life support parts I needed for a long stay, as I'm running MKS.

 

 

And here it is on Mun.  I've never seen a "Lode," so I landed near one and checked it out.  At that point, I was just under 300km away from Munar Station Ada Lovelace.  So time to start roving.  I was expecting it to be a tedious drive, so I've been working on a Rover Autopilot system made in kOS.  I've been playing with PID Controls for Cruise Control.  Problem is, I tuned it around flat ground near KSC, but it needs a lot of adjusting for the hilly terrain on Mun.  I'm averaging about 5m/s, so it'll be a while.  About half way to the station now.

 

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This looks awesome and very functional.

Perhaps include modlist? I don't recognize these wheels

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On ‎3‎/‎22‎/‎2017 at 8:56 AM, agrasyuk said:

This looks awesome and very functional.

Perhaps include modlist? I don't recognize these wheels

I believe the wheels were from Wild Blue Industries, as is the main rover chassis.  The washers / joints and piston are from Infernal Robotics.  Everything else is from MKS or USI Life Support.

I can put up a craft file when I get back in town.

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Meant to put this up earlier.  After the 300km trip to Mun Base Ada Lovelace, Bogie McBogeface is looking a bit worse for wear.  I'll have to fly in some kind of crane to hold it up, while I reattach the bogies (using KAS).  It's fairly obvious on the last part of this clip.  Though, using it as a bulldozer may not have helped.

 


 

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Posted (edited)

R.I.P. Bogie McBogeface (at least for now).

I sent a couple of guys in rover Bogie McBogeface to due a Munar surface rescue on the other side of the Mun using my custom kOS autopilot.  I set up a bunch of way points (fighting with Kerbnet), and it completed the first leg of about 80km no problem.  Set up the 2nd leg of about 120km, and left for dinner.

Came back to this:

Looks like it slid down the side of a crater, likely took a tumble.  Antenna looks broken off, and the differential bar is broken.  This is the chance to build a nuclear powered sky crane (finally unlocked NERVs) and send it in for a rescue, and possible repair.  At the very least, I should be able to remove the wheels, and attach them directly to the chassis, but it won't be a rocker-bogie system anymore.

Edited by Soda Popinski

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I love that idea!  I've always wanted something more interesting for rover builds and now I know what I'm gonna do!

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Posted (edited)

2 hours ago, SlabGizor117 said:

I love that idea!  I've always wanted something more interesting for rover builds and now I know what I'm gonna do!

It's not obvious in the proof of concept version, but you'll need to have washers / someway to pivot the differential bar.  I scaled down unpowered washers, mounted empty Oscar tanks on them, and put one on the rocker arm, and one on the differential arm (per side), for a total of 4.

Oh, I forgot to show the autopilot I wrote in kOS.  You can navigate either by specifying heading, or picking a way point.  You can even input manual coordinates.  The latest thing I put in was sequential way point navigation.  That's what got me in trouble earlier.  The embedded image is a bit blurry, click here to see the crisper version.
 

 

Edited by Soda Popinski

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