PDA

View Full Version : Bipedal Motion Synchronizer



Gilgamesh
05-29-2009, 01:14 AM
I've come up with a device to manage the leg motion of bipeds (and possibly quads with some adjustment).

As I've mentioned in my Bipedal Motion thread (http://www.lbpcentral.com/forums/showthread.php?t=8255), you want your leg to perform the following steps in order :

1 - Upper leg moves forward.
2 - Lower leg moves down.
3 - Upper leg moves backward.
4 - Lower leg moves up.

This takes a while to set up using the built-in Sync setting of wobble bolts and pistons, but thanks to the new angle setting on switches we now have a better way to do this. :)

Parts :

A large cube of any material.
A small rectangle of any material.
A motor bolt.
A magnetic key.
Two magnetic key switches, set to Directional and with 180 degree angle.


Assembly :

Set the rectangle piece on the large cube using the motor bolt so that it looks like the hand of a clock.
Set the magnetic key at the opposite end of the rectangle piece.
Set the first magnetic key switch at the left or right edge of the cube, making sure to align it with the motor bolt on the rectangle.
Rotate the whole cube assembly by 90 degrees using Grid Mode.
Set the second magnetic key switch at the left or right edge of the cube like the first.


Use :
Simply connect a magnetic key switch to the wobble bolts at the hip of your walker, then connect the other magnetic key switch to the pistons or bolts at the knees of your walker.

Adjust the "Backward" option on your pistons and bolts until you get the desired motion. Then you can adjust the speed of the motor bolt on the cube, and the wobble bolts and pistons, to whatever speed you want.

Here's what you should end up with :

http://i83.photobucket.com/albums/j294/Jirugameshi/LBP%20Bipedal%20Motion/bms.jpg

Hope you guys can get some use out of this. I know I will. :)

johnrulz77
05-29-2009, 01:29 AM
eh?

you should take a look at my quadruped spider....

it totally IGNORES all of your rules and tips, etc. and it walks on little points instead of feet,

btw, welcome back, considering you were SOOOOOOO un-active the past while

EDIT: u need 1 rep point for the 3rd crown (was looking for my stat and passed yours..)

Gilgamesh
05-29-2009, 01:42 AM
eh?

you should take a look at my quadruped spider....

it totally IGNORES all of your rules and tips, etc. and it walks on little points instead of feet,
I don't set any rules, I just share what I did and how I did it. I've seen more than a few walkers that have wildly different walking mechanisms than my own. I think it's great, because the more people experiment different approaches, the more we can learn and adapt new tricks. :)

In reality, the synchronizer can help manage any 4-phase, 2-joint motion. It isn't even limited to being used on walkers, so I hope people will find some creative uses for it.


btw, welcome back, considering you were SOOOOOOO un-active the past while
Yeah, I'm going to start being more active again now that things have quieted down a bit on my end.

johnrulz77
05-29-2009, 01:48 AM
yeah i became active right around the time you stopped, so i doubt you know me,

anyway...

my thing - a THING because it looks like an insect, yet i cant name it.....

is actually made with 8 wobble bolts,
4 on the body-upper leg,
4 on the upper leg-lower leg...

4 pistons on each connection between the upper and lower legs, (to give it more of a leg bending effect)

snowflakecat
05-29-2009, 03:04 PM
nice. awesome stuff as always.

Recurracy
05-30-2009, 04:23 AM
I don't get the picture. You were talking about pistons and whatnot... I really don't understand it.

Oh wait! A motor bolt rotates on the legs, while the part where the magnetic key is on doesn't rotate, so the wobble bolts move as desired?

Gilgamesh
05-30-2009, 12:14 PM
I don't get the picture. You were talking about pistons and whatnot... I really don't understand it.

Oh wait! A motor bolt rotates on the legs, while the part where the magnetic key is on doesn't rotate, so the wobble bolts move as desired?
I mention pistons because I use pistons myself instead of the knee wobble bolt shown in the picture. But you're correct : the motor bolt makes the key turn around, which makes it go in-and-out of range of the switches, which makes the wobble bolts (or pistons) alternate between moving clockwise and counter-clockwise.

Funny story : I accidentally attached the legs of my latest mech with motor bolts at first (instead of wobble bolts) and the device still made the motion work correctly, even though I had the wrong bolts! :)

This should help you get a clearer picture. I use Option 2, with reverse-knee joints.
http://i83.photobucket.com/albums/j294/Jirugameshi/LBP%20Bipedal%20Motion/leg2.jpg

Zwollie
05-30-2009, 10:23 PM
Cool stuff, Gilgamesh!!
I was just looking for some options for a bipedal character I'm making.
Yeah....it doesn't always need to be a robot or mech :)

dawesbr
05-31-2009, 03:29 PM
Cool post! I think I understand it :S I think simplifying sequencers like this is a really interesting thing to try to do in LBP, very nice work!

Silverleon
05-31-2009, 06:32 PM
yeah i became active right around the time you stopped, so i doubt you know me,

anyway...

my thing - a THING because it looks like an insect, yet i cant name it.....

is actually made with 8 wobble bolts,
4 on the body-upper leg,
4 on the upper leg-lower leg...

4 pistons on each connection between the upper and lower legs, (to give it more of a leg bending effect)

*cough*
Hm?
So did you make this all by yourself, are you sure you didn't get it walking because someone helped out?
;)