Orbiter-Forum  

Go Back   Orbiter-Forum > Projects > ORBITER: 2010-P1 and newer > Bug
Register Blogs Orbinauts List Social Groups FAQ Projects Mark Forums Read

Delta Glider Ground Steering and Braking Is Unstable Issue Tools
issueid=1135 05-16-2014 05:31 PM
Biblical Creationist
Delta Glider Ground Steering and Braking Is Unstable
Brakes will cause vehicle to skid (usually to the right) and"nose wheel is unrealistically slow

January 1, 2013 and later builds.

Upon landing, the wheel brakes of the Delta Glider will send the craft skidding (usually to the right) when both the comma and period keys are pressed at the same time. When the comma key is released, the vehicle spins into a skid in the opposite direction and starts an oscillation cycle when the comma and period keys are released/pressed (depending on the direction of the skid) repeatedly until the vehicle either stops or flips.

Also, the only way to effectively steer the Delta Glider is by using the wheel brakes. Nose wheel steering has a negligible affect on the vehicle's heading. By the time that the desired heading is reached, the vehicle has gone hundreds of meters from the desired path. But using the wheel brakes creates the oscillation problems described in the previous paragraph.

EDIT: I did search but didn't find anything.
Issue Details
Project ORBITER: 2010-P1 and newer
Status Unconfirmed
Priority 1 - Highest
Affected Version Revision denoted in description
Fixed Version (none)
Users able to reproduce bug 2
Users unable to reproduce bug 0
Assigned Users (none)
Tags (none)

05-19-2014 04:36 PM
Orbiter Founder
 
Nose-wheel steering isn't enabled in the current beta.

The fact that the DG is swerving on imbalanced main brakes could indicate that the lateral friction coefficient of the nose wheel is too low to counteract the angular momentum induced by a single main gear braking. You could try to play around with the fricition coefficients of the first three touchdown point definitions in orbitersdk\samples\deltaglider\deltaglider.cpp and see if you can come up with better values. It could also be that the braking power of the main brakes is simply too high.
Reply
05-19-2014 08:47 PM
Biblical Creationist
 
Actually, it now seems to be the wind that is causing the vehicle to start swerving when the brakes are first applied. I'll run a few more tests to confirm this. Perhaps it's not the nose gear's lateral friction that's too low. Perhaps it's the main gears' lateral friction that's too low.

Also, cutting the braking power down by a factor of 5 does seem to help remedy the problem of swerving. But I'm going to run several tests just to make sure. Both with and without wind.
Reply
07-14-2018 09:01 AM
Orbinaut
 
Good find.

Turn off Atmospheric Wind Effects in the Parameters to get the Deltas to run straight down the runway. Else a bit of practice with differential wheel braking and use of rudder.

A bit of discussion with Martin et all about atmospheric wind effects here.
https://www.orbiter-forum.com/showthread.php?t=38490
Reply
Reply

Issue Tools
Subscribe to this issue

All times are GMT. The time now is 05:34 AM.

Quick Links Need Help?


About Us | Rules & Guidelines | TOS Policy | Privacy Policy

Orbiter-Forum is hosted at Orbithangar.com
Powered by vBulletin® Version 3.8.6
Copyright ©2000 - 2018, Jelsoft Enterprises Ltd.
Copyright 2007 - 2017, Orbiter-Forum.com. All rights reserved.