[ranch vermin]

I pulled this up myself in visual studio,  its going to have all the brackets to put the robot body together as well as an eye, and the motor controllers i havent got working yet.
Its got a cute cross section thing happening, in my csg system.
Its drawn up by a weighted sum of defined measurements, so its all reconfigurable,  thats the bit im proud of.  The rest of it, is probably not going to work. 

Ill be getting top and bottom moulds done for this thing, and if i get the moulds done, they probably will just be a first attempt, and ill have to get more out of my wallet to get the next set that actually works, after i sort out my probs.



apart from...

a) my material wont be tough enough for cogs or decent bearings.
b) i dont have steel for the coil fins. (they are crossing each other in the core of the motor,  they all get a thick winding.
c) im thinking about putting the coils printed on thin sheet around the coil holders.  <-interesting idea.
d) my conductor im going to use is going to be pretty poor conductivity, and im going to get further losses.
e) my bearings will be weak so theyll have too much surface contact.

I wont know how dire my situation is until i press mould it, and wind the coils and watch it go - itll definitely turn under no weight, but holding itself against gravity is another question.
I definitely think if it could pull its own weight, its probably pretty tough, depends on how heavy it is.

Another interesting thing im trying is doing it without wires, it all gets passed up the axle.

[Korrelan]

 

[ranch vermin]

Thanks Korraz!!!  My systems not done yet, more improvements to make,  thanks for the vid.

Are u hinting that I shouldnt be using dc motor designs - IMO the stepper motor is not much different, and I dont get a huge gain in using it,  u showed me the "triad" system or something like that and its just as good, for the reason that, if you were stepping - you end up needing to step more than once, and it ends up not much different than pot controlled dc motor anyway. 

Thats how I think about it, right now.Theres no way to avoid the inevitable subtraction of "target-current position" in the motor controller,  so it needs a left and right message, and a dc motor handles that fine.

Ive got another shot showing off my variable parameters,  to make this engine i just retyped two values!!! and changed the perspective a little because orthogonal vision is very retarded.

[Korrelan]

Hi Ranch

Are u hinting that I shouldnt be using dc motor designs.

Not at all… a DC motor, reduction gear box and potentiometer is the staple design for most budget servos.

DC motors without a reduction gear box are pretty useless for bots, they are designed to run at high RPM’s with very little torque and precision.

Your diagram didn’t show a reduction gearbox between the feedback pot and the motors output shaft, so I presumed from your diagram of the rotor/ stator design that you where building some kind of stepper motor.

 

[ranch vermin]

definitely true.  that i need a gear in it.    what stepper motors i think are properly for is when you need count revolutions,  if you never make it past 360 degrees a pot+dc motor will do fine.

Ive been watching makers muse's cool printing videos and hes the gear box master,   im worried that my gears will break,   but ill definitely be onto them,  but they seem take something so simple and just make it so much more complicated, that i was thinking maybe not worrying about precision and seeing if it can lift itself without them.   but i know my battery has to be alot stronger, and the motor shell coils lacking ferrite will be really weak.  so its as if i need one for this, definitely,  but im just avoiding it.

the finished motor will look alot more adequate, this is just me starting up my boolean objects system.   The cool thing is I can get on with the rest of it, and finish the motors off last, because im using a part primitive reuse hierarchy.
I could make a whole city for a game just by myself with this program, its cool.

[ranch vermin]

Been awhile,  had too many bugs, and too many cigarettes at the same time, and its basicly floored me...  but i press onward...

i was doing oblique before,  now ive got proper escher isometric.   ill have a dithered beauty render later,  but im going to hopefully finished this (measured) bot tonight,  its going to be sent off to the net for the molds to be printed.  Getting excited!



computer is cylindrical,  and its housed in the centre,  the legs rotate attach to it, in 4 cylindrical quadrants.

[ranch vermin]

finally got to the basic idea,   theres alot to fix yet,  but the basic idea is here->




Heres the parametres for the build->

float body_thickness=15;
 float body_size=90;
 float axle_hip=2;
 float axle_knee=4;
 float axle_foot=2;
 float axle_protrusion=30;
 float magnet_thickness=10;
 float magnet_length=20;
 float shell_thickness=2;   //2cm is base thickness of the robot
 float fin_thickness=1;   //2cm is base thickness of the robot
 float eye_x=24;//no more than body size
 float eye_y=11;//no more than body thickness
 float bracket_thickness=10;
 float play=6;
 float foot_radius=10;

[ranch vermin]

curled the legs,   I actually didnt quite curl them enough to get his body off the ground.
Im planning on making the spin motors longer (itll give him "leg between his knuckles") and the brackets arent wide enough - its actually self intersecting here.   have to fix it,  nothing in a real robot is allowed to self-intersect,  in aesthetic graphics, its not important - but now we are making something REAL.

[ranch vermin]

had some more killer bugs, caused by my dizzy spell,  I was stuck on a type-o for half a day,  im hating it!!
But ive got a bit more -  I got the parametre hacks to work,  now the "spin bracket" has a longer version of the "yawpitch" bracket,  It needs it because there is only 1 spin motor per joint, plus I like the extra gangliness im getting. 

[ranch vermin]

Now I have to worry about the electronics -  the "nerve wires" or rather the motor controller wires are going to inside up past up the brackets and down the axle,  so the hip axle and brackets have to be thicker,
and its going to affect the ending result.  so off I go,  hopefully ill get it in less than a couple of hours, unless something goes wrong.



my system is reparametrizable,    next post ill show 3 varients of the same base design...   hopefully less than an hour.

[ranch vermin]

The varients arent 100% correct,  Ive got some measurement combinations that are wrong.    But this will do for now,  im now going to form the depth maps for the top and bottom molding im going to be doing.
Hopefully I can get it 3d printed soon.

[ranch vermin]

heres my happy result.   



https://www.youtube.com/watch?v=09_64HiItcA&feature=youtu.be

What im writing now,  is an automatic press mould conversion. (there should be about 30 moulds in this robot.,... but u have to assemble alot more repeats of them to get this finished thing.) im making it almost fully automatic,  thats the way I have to be from now on.  All u have to do as the user is declare a plane, then it handles the rest automagically.

[Freddy]

Really interesting. I've never done modelling programmatically, this is all new to me. I'm a vertex pusher and puller 

I can see that if you are going to get this printed then you need exact measurements like this though.

Cool work 

[ranch vermin]

Thanks Freddy  ,   indeed - you dont want anything too skinny, nothing is allowed to self intersect, things I didnt have to worry about when I was younger just making game assets.

I imagine people with less confidence in illustration maybe could even prefer just typing it in.    Im going to take what I have and put out a humanoid, ill post how long it took me, and im not going quick at all, and it shouldnt be long.

Its the same base parts,  just in a different configuration.

Since im only a fledgling engineer -  there is definitely going to be changes from here,   now what im afraid of, is electromagnets have to be the densest iron and densest windings or they havent enough power,  and ive got cooling to worry about alot, not enough torque... its just going to up in a puff a smoke.

And its going to be more expensive than I first thought as well.

[Art]

Nice design but if you'd rather skip to the humanoid part as you mentioned and still do some 3D printing, plus get a ton of help from a lot of great idea people from an established community, give a look at: http://inmoov.fr/

Just a suggestion...