89Views6Replies

Author Options:

OAWR Legs Lock Up Answered

I'm currently assembling an Obstacle Avoiding Walking Robot, however I find the legs keep locking up.  Basically, as I move the legs the nuts are tightening to the point where the legs won't move any more.  I have washers in all the correct places so must be missing something else.

Any tips on how to avoid this?

Thanks.

James.

Comments

The forums are retiring in 2021 and are now closed for new topics and comments.
0
jsluke
jsluke

7 years ago

Thanks for all the comments.

The answer was to use locking nuts - I replaced the double nuts in the design with nylon locking nuts and then adjusted to get the right level of tightness.

Thanks again for all the advice - much appreciated.

James.

0
Josehf Murchison
Josehf Murchison

7 years ago

Key the nuts.

Locking keys are used to keep nuts from loosening off and they are also used to keep nuts from tightening.

It can be as simple as drilling a hole through the nut and bolt and using a spring pin or cotter pin to lock the two.

You can just use a locking nut. (Nut with plastic ring to grip threads.)

Double nut it, put two nuts on the bolt and turn them to each other to lock them.

Cross a thread, damage a thread with a chizle or a screw driver even vice grips at the point where you want the nut to stay then thread the nut over the damaged aria and it will stay there.

Liquid lock washer; a glue made to lock nuts.

These are just a couple things you can try.

Joe

0
Kiteman
Kiteman

Reply 7 years ago

I'd go with the double-nut option as being the easiest to undo or adjust during the R&D phase of a project like this.

0
Josehf Murchison
Josehf Murchison

Reply 7 years ago

I would also but I don’t know how long his bolts are.

0
Josehf Murchison
Josehf Murchison

Reply 7 years ago

I just thought of another one if you don’t have a lot of space for double nutting drill one side of the nut tap it and use a set screw.

0
caitlinsdad
caitlinsdad

7 years ago

Any pics of your robot? Mechanical linkages will bind when the pivot points were not accurately machined on your legs. Any warpage of the parts? Is it the connected motor or gearing binding up when it gets to a certain point? You might have the weight of the robot bearing down on it too.