August 10, 2013

Meeting Date: 
Saturday, August 10, 2013

Robotics Society of Southern CA, August 10,  2013 Meeting

Minutes: Walter and Patricia

Special Interest Group (starts at 10am every meeting): an Artificial Intelligence Robot

Topics: Garry’s new Leaf platform and Bluetooth Leaf connectivity by Dr. Bruce and Garry.

Class (starts at 11am every meeting) : 3D Printing by Patricia

On an hour’s notice Patricia brought in a loaner 3D printer from It was one of the first Bukito printers. Patricia was able to demonstrate the different software packages available for free.  Members discussed topics such as the coefficient of expansion , static warp, slicing and the darker the consumables are the more likely fumes will be produced due to the dye. Other topics included print envelopes, heated platforms, cost and types of materials plus speed. Patricia concluded the presentations by finishing printing a very nice World Cup trophy.

Trish's notes: Issues discussed were :

Expect lots of failed prints.  Each person needs to familiarize him/herself with the material.

Trish showed some of her failed prints.  And discussed why they failed: non-manifold design, warping, base not sufficiently levelled.

Thickness of filament discussion:  Too thin, nozzle will be fighting the plastic.  Too thick, the extruded plastic won't melt properly.

Heated platform important to prevent model sticking to base and reduce warping when plastic cools.


Trish's warped planetary gear bae may have been due to the outside temp cooling over the duration of the print.

Different plastics and different colors of different plastics have different coefficients of expansion.  Need some more info on this. 

Sergei: Darker-> more dye, better to get colorless.

When building gears and mech parts prefer ABS (Sergei)

Find some parts on Thingiverse to print.

Software used by those present:

Design software: SolidWorks (very expensive), Free options - Open SCAD, Sketchup (seems like too much work), TinkerCad, Blender.

Note: If you want absolute placement of your part, you want a formula based design tool like Open SCAD.

Slicing tool prior to print. Uses the STL file.= Repetier Host and KISS Slicer.

DeltaB is another type of 3D printer, with 3 posts, cylindrical in shape.

Expect to pay about $50 for a 2.2 lb spool of filament.  Filament manufacturer will have different quality, and even within manufacturer over time, you may find quality changes.  Sergei had issues with a bump in the filament which caused his print to fail.




RSSC is proud to be a participant of the 2013 Orange County Mini Maker’s Faire. Thanks to all the volunteers!

A new competition was proposed by Walter where a bipedal robot kicks a soccer ball to try and score. To make it more interesting the robot has three chances of kicking the ball to the goal at different angles. The robot who can kick the ball and come close to goal or score a goal.  This will be the competition for next month’s meeting 8/14/2013.


Next month’s class is on how to connect any sensor to the Lego NXT by Prof Mason. We will possibly have a presentation on the new Lego MindStorms kit V3.



Mini Urban Challenge organized by Prof Mason  was a success with so many participants from Mount San Antonio College.  We had  great prizes again for 1st  (color touch screen for the Arduino donated by ,  2nd (tickets to the Santa Ana Science Center – The Cube) and 3rd (Robot Builder Bonanza’s book)place.


Carl  from recommended to use stepper motors and spoke about the pros and cons of using stepper motors.  He also recommended to look into the videos of Giant Robot Project on youtube.

Bob – I was on staff for the Boy Scout Jamboree July 2013 for the robotics merit badge. 35000 people attended and 700 youth built a robot. Some kids wanted to build a robot just for fun and others wanted to earn the badge. For the badge, boys need to start an engineering notebook and sketch a robot design, devise a task, and make improvements as needed. 2 of the 7 requirements were earned by many of the kids. Vex has a new plastic snap-together kit which we used so they wouldn't need to assemble tiny parts. It is not as functional as Lego Mindstorms (only 2 bump sensors included) and programming was done in another booth on a different platform.

To get boys enthused about robotics and programming.

–All ability levels from no LEGO experience to FIRST (For Inspiration and Recognition of Science and Technology )/ FRC Competitions.

–Some just wanted to build and try it out

–Some wanted to learn programming

–Many learned how to build a mechanical design for the first time.

Boys who wanted to earn a second merit badge requirement could do programming in an adjacent booth or flowcharting the task. Programming merit badge was also introduced along with game design, welding, and sustainability badges.

Requirements can be found at:

Patricia – spoke and brought a book about Karakuri

Garry – demonstrated his new Leaf platform based on Parallax’s Eddie wheel kit and base. Garry showed how he can use Bluetooth to communicate with his robot from a remote laptop.,ProductName

Sergei – demonstrated some 3D printed parts from his own printer  (a Delta Print model). Software mentioned were OpenSCAD, Rosctock, Kisslicer, Printerface from Blue Eagle Labs.  Sergei also showed how you can use common items from HomeDepo such as the lazy susan and caster wheels for his robots.

John – added a nice custom printed sign to the It Work At Home (IWAH) trophy, plus replaced batteries to make all the other add-ons work.   Thanks John!


This award is given to the person whose demonstration failed, but It Worked At Home.

The recipient is expected to add something to the award then return it at the next meeting.

Walter – talked about the projects he is doing with Bob at KidsTalkRadioLA  and

They are working on creating an educational program to cover STEAM subjects for the world.


Next Month


September – Test your soccer robot skills – bipedal walking robot contest (cancelled)

October - Object Tracking Contest

November – 16oz BattleRobots follow RFL rules

Video from the RCX - Expo in Long Beach, competition by Prof Mason

Dec – Yearly Talent Contest


September – Lego NXT Sensor Interfacing