Why won't this rover dock?

[mr_trousers]

So I've just started a game on sandbox to try to do some things. I'm working on getting a base on the moon right now, but I'm doing some testing on the launchpad first to make sure everything works. I made a rover, and I'm having a lot of trouble getting it to dock with the base --

As you can see on the navball they're pretty close to lined up. I had it completely lined up before, like they were touching and the target reticule was exactly centered, but I didn't take a screenshot, and I got a little hasty when I went back to do it again. But anyway, even when it was even more precise, the docking ports just don't seem to engage. Am I doing something wrong?

Here's the two docking ports separated... maybe I've just built something wrong. This is the first time I've ever attempted docking, in any case, lol. Also the first time I've ever attempted base or rover design.

Edited May 9, 2015 by mr_trousers

[Strupo]

Pictures weren't showing up for me so FIFY

Edit: looks like you fixed it yourself

[Randazzo]

Try right clicking the port on your rover and select "Control from here" and set the other port as your target. I don't know if that's actually necessary but I've never docked without doing that first.

[mr_trousers]

Try right clicking the port on your rover and select "Control from here" and set the other port as your target. I don't know if that's actually necessary but I've never docked without doing that first.

Mhm, I've done that. I tried to follow a docking tutorial after it wouldn't work at first (though those are generally about docking in space, so a lot of it wasn't applicable), so as far as I know I'm doing everything you're supposed to do, it just isn't ever engaging and docking.

[Reddeyfish]

one of the old workarounds is to switch to the space center and back once the rover should be in docking range.

If not, then try using some form of locked suspension so that the docking ports are exactly at the same height.

[nigelvn]

Happened to me as well, it probably doesn't dock as they are not 100% aligned and they cannot move around (as they aren't in space). This is the exact reason I prefer to use the claw on rovers, are a bit big and clumsy though.

[wossname]

I wonder if you're colliding with something else before you get to the docking distance. Try adding a couple more octagonal struts to push the docking port out a bit more (sometimes size does matter!).

[mr_trousers]

I wonder if you're colliding with something else before you get to the docking distance. Try adding a couple more octagonal struts to push the docking port out a bit more (sometimes size does matter!).

I'll try this just to be sure when I get the chance to get on the game again in a couple hours - though I do feel like I checked the corners and nothing was colliding.

If not, then try using some form of locked suspension so that the docking ports are exactly at the same height.

How uh... do I do this?

Happened to me as well, it probably doesn't dock as they are not 100% aligned and they cannot move around (as they aren't in space). This is the exact reason I prefer to use the claw on rovers, are a bit big and clumsy though.

I saw the claw when I was going through parts building my rover, but I'm afraid I have no idea what it does. Is it a functional replacement for docking ports?

[Krawdad]

One thing that I have encountered in the past while doing similar docking trials is that you may need to create a bit of distance between the two ports after the initial disconnect so that the game doesn't think you are still trying to undock. Like the docking magnets don't turn back on until you are done undocking. Though I can't really tell from the pictures if this applies or not, as you look pretty far away from the port.

Could it be that the magnets are kicking in, but they aren't strong enough to move the craft while on Kerbin? Maybe setting the brake torque to 0 would be enough to let the magnet work? Or give the wheels a little jolt to help the magnet do its job?

Also, that is a very cool rover and the design gives me some ideas for my own attempts at Munar mining/refueling

Edit: and yes the claw is very handy for docking. I only just found out that you can transfer resources through it once you have something grabbed -- like a fuel tanker. The large "No Fuel Crossfeed" label in the description might have been what led me to never try it previously...

Edited May 8, 2015 by Krawdad

[mr_trousers]

With a couple design changes and replacing the docking structure on the front with a claw, I've managed to get it to dock to the base! Thanks guys! Nothing else was really working, I tried making the docking structure longer and I also installed mechjeb and told it to autopilot dock (though it didn't do a lot since it has no RCS, but when I got really close the autopilot disengaged as if it believed I had docked). I didn't do anything with "locked suspension" as I don't know what that is, so maybe if I'd figured that out and got the heights really aligned it would have worked, who knows.

But anyway, since I found a method that worked, I'll marked this as answered. Thanks again, everyone.

[cicatrix]

Just want to share my experience. Once I made rovers which docked perfectly... Then I mined some karbonite and tried to dock again. I couldn't because a loaded rover became heavier and the ports were unaligned - the one on a rover lowered a tiny bit but enough for not being able to dock.

Try docking empty and see what happens.

[RexKramer]

There are a lot of tricks to making docking work with rovers. Unfortunately, none of them has worked reliably for me.

So, I solve the problem by mounting a Claw on the mobile rover. No more alignment issues, solves a lot of problems.