Wednesday, January 22, 2014

Making a Full Color White Light Hologram

Using 123D Catch iPhone app, I captured a model of my wife Carla, and then took that an made an 8x10" full-color white light hologram from Zebra Imaging:

My thoughts:  123D Catch is pretty easy to use to capture a 3D mesh.  Making the hologram from the mesh on was pretty easy as well - they interface well with Zebra Imaging.  I probably should have fixed up the mesh a bit in Blender or MeshLab, but I had to use a coupon before it expired.  The hologram has a kind of "grid" to it, but you don't tend to notice it very much.  The hologram is not very efficient, you need to illuminate it with a very bight light to see anything.  I ended up purchasing an Ikea Jansjo Desk Work Led Lamp Light, which does a good job of illuminating the hologram because it is a point source, single white LED.  Pretty awesome!

Here is what the mesh looked like in MeshLab after I captured it:

Crashspace's Sparkles in 3D

I did a quick 3D model of Crashspace's "Sparkles" the pony soldering iron using the iPhone 123D Catch app, here are the results in MeshLab:

Needs some work in Blender.  You can see that I put Sparkles on top of a drill press to capture the model.

Saturday, November 09, 2013

Dorkbot SoCal 55 on Sunday

Dorkbot SoCal 55

***** Sunday, November 10, 2013
***** 1:00 pm to 3:00pm
***** LA Biohackers Lab
***** 6th Floor, ETO Building
***** 1340 E 6th Street, Los Angeles, CA, 90013

Come meet the LA Biohackers and find out more about some of the biotech projects going on in their lab! 

Speakers to include...

Keoni Gandall
Keoni will be talking about how he is bootstrapping a synthetic bacteria using the common laboratory bacteria Bacillus subtilus. Currently there is no easy method for creating a new organism even if you have the ability to synthesize a new genome from scratch. A method Keoni is working on allows for a new genome to first be integrated into a host genome, then split off during cell division to create two daughter cells - 1 with the host genome and 1 with the new genome. This method will have great use in synthetic biology. 

Sophia Hewitt

Sophia will be talking about her research on using epigallocatechin-3-gallate (EGCG), a compound found in green tea as an anti-tumor treatment. In some types of cancer the cancer cells repair their telomeres so the cells effectively don't age, allowing the tumor to grow perpetually. Sophia is testing whether EGCG can inhibit this telomere repair mechanism and allow for treated cells to age. She is usingthe model organism called Tetrahymena thermophila which is an excellent test bed for studies on telomere length. 

Cory Tobin

Cory will be talking about his work on creating plants that make their own fertilizer. He is studying an extremophile bacteria that makes it's own ammonia (fertilizer) using water and nitrogen gas from the atmosphere. By understanding the mechanism this bacteria uses, he hopes to create plants and algae capable of synthesizing their own ammonia, negating the need to apply fertilizer to the soil. 

Monday, June 17, 2013

Lynxmotion AL5D Arm Inverse Kinetics reference material

The best theoretical analysis of inverse kinetics for the Lynxmotion AL5D robotic arm can be found here.

Furthermore, someone has already coded up the AL5D arm inverse kinetics code for Arduino.  I've ported this to Python and a quick test shows it appears to be sane (with some hack tweaks to make up for different initial angles of my servos), but I need to do more extensive testing.  I suspect the initial angles of my servos are different than most typical AL5D applications as I've set everything up to maximize reach for moving chess pieces, so I'll have to calibrate those angles into the code.

Tuesday, June 11, 2013

Arm Movement and Need for Inverse Kinetics

I extended my Arm controller Python program to be able to map and save the locations of chess board positions.

So here is a video of the "Mechanical Turk" arm moving a chess piece across the board using forward kinetics:

And here is the result of trying to move to another square:

Oops, I crashed into the board!  So I think I may have a go at calculating the inverse kinetics to avoid the arm from crashing into the board or (more likely) neighboring chess pieces.  The arm has to move the end effectors pretty much straight up a few inches to clear all the pieces, then it needs to move above all the pieces until it is directly above the destination square, then it needs to move directly vertically down.

I could probably heuristically do this with forward kinematics (for example, move up and down first by just using the elbow or such), but if I can get the inverse kinematics working OK it would give me a lot more control over the system.

Friday, June 07, 2013

Dorkbot SoCal @ Crash Space Sunday, June 9

Dorkbot SoCal 53

***** Sunday, June 9, 2013
***** 1:00pm to 3:00pm
***** Crash Space
***** 10526 Venice Blvd.
***** Culver City, CA 90232
***** (Directions)
***** No cover charge / donations to venue welcome

Come to Crash Space and learn about the hackersapce and some of their exciting projects:

Mechanical animation kit.


Crash Library
Arudino-powered outdoor mini-library that tweets when people take out a book.

Crash Inspired
Mobile interactive night club experience - 2K RGB LEDs - on a truck - controlled with Twitter!

Wednesday, June 05, 2013

New end effector

I added a new end effector to "The Turk" arm.  The Lynxmotion Little Grip has screw holes for 4-40 bolts, so I added two pieces of copper pipe hanger that just happened to be the right thickness.