RoboSavvy Forum

First Attempt to print out DARwIn-OP brackets!

2011-07-20T23:33:48+01:00

Tried out the brackets with a RX-24F!

http://mike-ibioloid.blogspot.com/2011/ ... acket.html

Statistics: Posted by Gort — Wed Jul 20, 2011 11:33 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-15T03:46:56+01:00

Looks like we just hacked the brackets! Hooyah!

http://mike-ibioloid.blogspot.com/2011/ ... in-op.html

Statistics: Posted by Gort — Fri Jul 15, 2011 3:46 am

First Attempt to print out DARwIn-OP brackets!

2011-07-06T21:59:18+01:00

It was set to fill 100% and I never use extra shells. 0.4mm layer height.

I do have my cooling set to slow down with a minimum layer time of 20 seconds. This could be a problem for the top of the print, but the lower side of part is still too weak.

The only other thing I can think of is that my print temp swings have been getting worse over time. +-10 degrees! Still, I keep it high enough so the low side of the swing is 220. Maybe the variance causes substantial weakness? I guess I should look into tweaking that.

Statistics: Posted by billyzelsnack — Wed Jul 06, 2011 9:59 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-06T20:46:39+01:00

billyzelsnack wrote:
Looks great.

I was inspired to print one out myself. Once again I am seeing the same problem with printing brackets. The side wall strength is pretty poor because of layer delamination. I really want to figure out why. Yeah my print has other various issues, but right now I am more concerned about part strength. Any ideas on why your part is so much stronger than mine?

http://www.youtube.com/watch?v=e0YZ_9ERO7s

BTW. How wide did your bracket sides end up printing out? The model is 2mm and mine ends up at 2.32mm.

Without seeing your profile settings I can't really say. With any thin-walled object you want to take -Extra Shells- under Fill to all zeros. I also have an infill of 1 or 100%. It could be the layer height and I am putting out a bit more plastic then I should be. So to confuse things even more the filament really isn't complety uniform so with this version of rep g you have to fudge it a litte and play with the filament size up or down, I can't seem to remember which way, to adjust plastic output. I'm not doing justice to how much math is happening behind the scenes with respect to amount of plastic being extruded/entering/exiting the nozzle. I don't fully understand it but I know it works. I have to also track down a few vibrations somewhere because any play anywhere transfers to your model output.

Statistics: Posted by Luis Rodriguez — Wed Jul 06, 2011 8:46 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-06T20:38:28+01:00

billyzelsnack wrote:
Looks great. What layer height?

.3 and I'm using the .4 nozzle with the cartridge heater. (Mk6+) That naming convention is starting to get silly.

I use 5D version of RepG 24 (Skeinforge 40) which you just put in the filament diameter (Dimension) and that is about it. You can adjust speed and retraction/reversal but I no longer monkey with W/T values.

I am going to try Rep G 25 though. I had the best out of the box experience with Rep G 24's default profiles so I am curious.

5D Rep G 24 - https://github.com/giseburt/ReplicatorG

Luis

Statistics: Posted by Luis Rodriguez — Wed Jul 06, 2011 8:38 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-06T19:20:47+01:00

Looks great.

I was inspired to print one out myself. Once again I am seeing the same problem with printing brackets. The side wall strength is pretty poor because of layer delamination. I really want to figure out why. Yeah my print has other various issues, but right now I am more concerned about part strength. Any ideas on why your part is so much stronger than mine?

http://www.youtube.com/watch?v=e0YZ_9ERO7s

BTW. How wide did your bracket sides end up printing out? The model is 2mm and mine ends up at 2.32mm.

Statistics: Posted by billyzelsnack — Wed Jul 06, 2011 7:20 pm

Darwin Parts on the Thing O Matic

2011-07-06T18:16:22+01:00

Yes, be kind to my Ultimaker friend, he is still tuning Skeinforge, we are using this project as an excuse to fine tune. I've done pretty well, I still am putting down a little too much plastic but this part is definetly Usable and will compete the entire Darwin in this awesome UV Red. I'm not sure I have the scale right just yet but that is easily fixable. Anyways, the race is on!

This Flickr set shows how clean it was after the print was finished, if I do say so myself.

http://www.flickr.com/photos/luiserodri ... 007269603/

I'll keep working on it tonight and tomorrow evening. Brackets dont' seem to be the problem, the head and body will be fun!

Statistics: Posted by Luis Rodriguez — Wed Jul 06, 2011 6:16 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-06T17:24:09+01:00

My friend Luis just print out this bracket last night with his Thing-O-Matic! He said it was as strong as the brackets on my robot!

http://www.thingiverse.com/derivative:10965

Statistics: Posted by Gort — Wed Jul 06, 2011 5:24 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T23:36:27+01:00

We think the Ultimaker can easily do it. My friend who owns the printer is fine tuning it now. The two brackets we printed where his first major prints. It is just a matter of time before we are printing out body shell parts!

Statistics: Posted by Gort — Mon Jul 04, 2011 11:36 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T20:16:16+01:00

Well that turned out about as expected! haha.

http://www.youtube.com/watch?v=RakNBxjwLbc

At 50% this thing is almost a worst case scenario for a FDM printer with sparse supports. Everything is a single thread thick with lots of overhangs and supports. My cupcake bed is too small to print the body out at 100%, but maybe I'll give a try to chopping it into 4 and printing at full scale.

Statistics: Posted by billyzelsnack — Mon Jul 04, 2011 8:16 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T17:07:34+01:00

If you retain the CM-510, this probably prevents the head pan servo being in the torso, so you need a head design with both pan and tilt. plus camera.

Accelerometer and gyro are best direct on DMP if you use CM510.

The robotis code does not use dynamic walk, so only kinematics need analysis, not dynamics.

It is not the gaits of the premium which are of value, but the get up routines and similar.

I don't have CM-510, but you may look at using with LN-101.

Statistics: Posted by i-Bot — Mon Jul 04, 2011 5:07 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T16:25:51+01:00

Pan Tilt Video camera ? - yes
Linux processor ? - yes + wifi
Gyro ? - yes - same as Darwin
Accelerometer ? - yes same as Darwin
Sound ? - nice to have
Head and Eye LED ? - nice to have
Force sensing resistors ? - where ? the CM510 can collect sensor input and the linux board can get additional sensors via an I/O board such as arduino attached to one of its USB ports.

The torso and head will need some redesign to adapt to a non fitPC2 computer and to CM510. for ball tracking and simple openCV and inverse dynamics gait generators + wifi, the DMP boards should be more than enough.

The weights and inertias will have to be recalculated in order for the dynamic walk generators to work. original gaits from premium may work.. maybe.

printing the smooth outer shells is a challenging with Markerbot or similar 3D printers. maybe printing them with Makerbot and then using them as molds for fibreglass to create the actual shells should get better results.

btw: the linux will connect to the CM510 via the zigbee port and ftdi because the RS232 is limited to 225kbps. if i recall from CM5 dissection times, the zigbee port on the CM510 is converted to 3.3V but should not have any speed constraints. right?

Statistics: Posted by limor — Mon Jul 04, 2011 4:25 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T14:23:07+01:00

Hi Limor,

Is your goal to achieve a look alike, or to have the same functions ?

If functions which of these do you consider is essential ?

Pan Tilt Video camera ?
Linux processor ?
Gyro ?
Accelerometer ?
Sound ?
Head and Eye LED ?
Force sensing resistors ?

The major part of the design is the torso and head. The above functions have most impact on that.

It is better to keep as close as possible to the Bioloid premium on joint layout, so you don''t have to make new motion files for the moves other than walking. Walking is with the DARwIn walking module, other moves are created in Roboplus.

Statistics: Posted by i-Bot — Mon Jul 04, 2011 2:23 pm

First Attempt to print out DARwIn-OP brackets!

2011-07-04T01:15:10+01:00

The Darwin CAD models really are amazing. All the parts are there. The body shell is quite large and will be difficult to get a quality print. Especially difficult because its curves require a LOT of support. I'm going to use it as a test benchmark for the printer I'm building. In the mean time I'll probably do a print at half scale on the cupcake tonight and see how it comes out.

Statistics: Posted by billyzelsnack — Mon Jul 04, 2011 1:15 am

First Attempt to print out DARwIn-OP brackets!

2011-07-03T23:51:13+01:00

Yes

Statistics: Posted by Gort — Sun Jul 03, 2011 11:51 pm