hey matt yeah that does work out correctly. thank for the help...

i figured i was using the "^" operator wrong here....

cheers

m

On Wed, Jan 25, 2017 at 11:10 AM, Matt Barber <brbrofsvl@gmail.com> wrote:

In expr, ^ is bitwise-exclusive-or, but you want exponentiation. Just replace $f1^2 with $f1*$f1.

On Wed, Jan 25, 2017 at 11:03 AM, me.grimm <megrimm@gmail.com> wrote:

Hello,

I am trying to calculate inverse kinematics in 2D space with 2 DOF according to this tutorial(1) and formulas within using [expr]. For some reason my calculations for "c2" using [expr] deliver quite a different result than the excel sheet calculation that the tutorial provides.

What am I doing wrong here? It may be I don't quite understand how "^" is used?

Using:

Linkage 1 length of 5

Linkage 2 length of 4

and plotting my the end of joint 2 at (3.56, 6.43) I should get c2 to equal 0.3254625 but get 0.25 with [expr]. Because of this further calculations to get joint angles are also off, obviously.

attached is patch.

but maybe someone has already done this type of work which might save me some trouble...

cheers

m

(1) http://www.societyofrobots.com/robot_arm_tutorial.shtml#inverse_kinematics

--

____________________
m.e.grimm, m.f.a, ed.m.

syracuse u., tc3

megrimm.net
____________________

_______________________________________________
Pd-list@lists.iem.at mailing list
UNSUBSCRIBE and account-management -> https://lists.puredata.info/listinfo/pd-list

--

____________________
m.e.grimm, m.f.a, ed.m.

syracuse u., tc3

megrimm.net
____________________