Tom Lohre's Art Making Machines

On Friday January 5th at 9:23pm the art robot received a computer brain. It has been 18 years trying to get a images' information fed to a robot. The big problem was discovering affordable software and hardware. Lego supplied this in 2003. It took four years to learn enough of the computer language LabView to write a program that takes information from an image and feeds it to a RCX robot.

2007 Robot Artist

Made from Lego parts. The software used is LabViews RoboLab. 

The Cincinnati Post On-Line Story about the robot

Show of Lego Artisto's New Work January 2008

Complete Press Release: http://tomlohre.com/sitwell.htm

Sitwell's Coffee House, 324 Ludlow Ave., Cincinnati OH 45220, http://www.sitwells.net/, 513-281-7487 The Story:

April Show of Art Work by Tom Lohre and a Lego Robot Assistant
Opening: Friday, April 18th, 2008, 6 to 9 p.m. Closing May 18th
Visual History Gallery, 2709 Observatory Ave, Cincinnati, OH 45208, http://visualhistorygallery.com , 513-871-6065, Hyde Park Neighborhood
Free, No reservation needed. Children welcomed.
Opening: Friday April 18, 2008, 6 to 9 p.m., light refreshments served.
Open: Open Tues-Thurs: 11-6, Fri: 11-5, Sat: 10-3:30, Sunday by chance or appointment. Closed Monday
Web Site: http://visualhistorygallery.com

The Story
In 1980 Tom started exploring the possibility of having a machine paint. In 2003 he discovered Lego's MindStorm Robotic system and spent four years learning the software. On January 5th, 2007 at 9PM Tom finally cracked the code to write a program that took information from an image in the computer and fed it to a robot.

In the past year, Tom has learned that “Artisto”, the name Tom has given to the robot, is like a classical assistant. Artisto lays one of eight colors in generally the correct spot and Tom manipulates it to refine its placement. Tom initially creates an image in the computer that Artisto follows. The painting process takes 18 hours for a 16” x 20” having 4163 dots. Tom can turn “Artisto” off while working on a painting so the painting does not have to be done all at one time. All the paintings in the show are close ups of faces because the resolution is so low that he has to rely on the viewer to fill in the blanks.

In the future, Tom sees “Artisto” having 16 colors to select from with Tom working closely with Artisto continually adjusting the paint as it is laid down.

Link to the paintings in the show: http://tomlohre.com/newart.htm

Link to the brochure: http://tomlohre.com/VHG08.pdf

2004 Robot Artist

In the past he has used a sweeping manner to cover the surface. The robot brush had to be guided by pushing buttons.

 The Robot

LabView virtual front panel

LabView program diagram

For the last twenty years Tom has been trying to develop a art making robot that would see something and then paint it. The problems were many but the worst was not being able to afford the components. When Lego came out with it's RoboLab software there was a good chance it could do it.

The robot is a simple x,y table using novel screw treads to position the pigmented wax crayon. The math on such formulas to position the pigmented wax crayon according to the image's x,y coordinates systems is doable even if the accuracy is not all that great.

Over-the-Rhine Alleyway, 16” x 20”, Oil on canvas

The above painting is a good example of the art the robot is producing. Tom wanted the 2004 robot to be able to work from a image in the computer but the learning curve is too steep for LabView the programming language Tom is using.

Pantograph Painting Robot of July 2003

Pantograph Robot

Wood strips, Lego RCX Brick, servo, IR sensor, pigmented wax, hot table.

    You can see that it is a very simple pantograph where one of the servos runs the print and plate heads back and forth across the work and plate. The IR sensor reads the black and white plate and the wax color stick is melted as it goes back and forth across the heated canvas.

    The robot needs the quick response from the IR head but since the IR head moves about 2 inches a second it fails to reverse the direction of the pantograph until moving about ½ inch. Slowing down the servo so the system has better reaction time following the plate will be tried next. The hypothesis is that the resolution will be improved but still about 6/8" x 6/8".The play in the machine is about 1/8". Moving the head in one direction would cut the sensor resolution in half.

Complete View of Robot

    This is all extremely exciting. Working with the Lego system for several weeks has proved about seven different types of robot painters. The latest one using the pigmented wax stick on a canvas heated by a hot plate creates by far the most beautiful surface. The pastel took several passes to get proper coverage. The fact that you can create any color wax stick you want has a very important meaning when you are trying to create something with something this rough. Slowing down the system allows you to move the print head to cover the surface more efficiently  but you give up the ability of the constant sweep of the printer head to allow you to see more of the image being copied.

Wheel

    The robot needs one driven axis. The other axis is gravity because tilting the drafting table cause the painting head to sweep across the canvas.

    It turns out that you spend more time making the robot paint than if you did it yourself. Time will tell if it can someday be an asset.

Large Format Pastel Printer June 25th, 2003

Used to produce 26" x 40" pastel printer by placing the black & white plate above the robot. The IR sensor causes the robot to reverse direction when it moves off the black plate. Random movements cause the robot to no repeat it's path thereby filling in areas as it travels back and forth across the black plate.

The beginning of the rotating print head used for the 2007 robot.

Version 1, This was to be a complete unit that had two wheels that would maneuver around the canvas but inputting the data into the light detector was not invented. I thought about using a 45-degree mirror but never got to this stage when I saw the beauty of using the pantograph device shown below.  This robot uses Alpha Stepper motors and a Radio Shack Color Computer. I have used these stepper motors for various researches into an eventual autonomous robot artist.

     The first project was to create a four-plunger type painting head that would secrete oil paint in measured, repeatable amounts. That project was completed with success in 1990.  The above arrangement uses a photon sensor from a photo lab device to feed light data to the Color Computer. Various filters revolve around the cathode tube to determine color. The motors under the black box drive the machine. The motor to the left will attach to a color pastel wheel that will rotate and then stroke the canvas in the appropriate way. The pastel's contact with the papers surface will act as the third leg.

     The computer control program for the steppers has been finished and now the sensor data as to be converted to +-5 volts and fed into a joystick.

     I still have to work out the focusing of the eye.

 Small Novel Art Robot

Remot Controlled Artist 1999

Art Robot Idea

Spider Artist, 1998, A series of balancing sticks with stepper motors for position control via balancing.