3-D PRINTER HAVING MOTION SENSORS

1 . A system for printing a three-dimensional object in accordance with a specification of the object comprising:

a print head for extruding a print material;

a build platform for receipt of the print materials;

an x-y axis translator for moving at least one of the print head or the built platform in an x-y plane;

a z-axis translator for moving at least one of the print head or the build platform in a z-axis plane;

a print head sensor for monitoring the position of the print head;

a build platform sensor for monitoring the position of the build platform; and

a controller for receipt of a signal from the print head sensor and the build platform sensor which generates an error signal to the x-y axis translator and the z-axis translator to minimize unwanted positional error in the x-y plane.

2 . The system of claim 1 wherein the x-y axis translator is a stepper motor.

3 . The system of claim 1 wherein the z-axis translator is a stepper motor.

4 . The system of claim 1 wherein the print head sensor is a motion sensor.

5 . The system of claim 4 wherein the motion sensor is one of an accelerometer, optical motion sensor or piezoelectric sensor.

6 . The system of claim 1 wherein the build section sensor is a motion sensor.

7 . The system of claim 6 wherein the motion sensor is one of an accelerometer, optical motion sensor or piezoelectric sensor.

8 . A three-dimensional printer comprising:

a nozzle for dispensing print material;

a table for receipt of the print material;

means for sensing an actual x-y axis and z-axis position of the nozzle and the table;

means for comparing the actual x-y axis and z-axis position of the nozzle and the table with a desired x-axis and z-axis position of the nozzle and the table and calculating an error signal if the actual x-y axis and z-axis position and the desired x-y axis and z-axis position are not the same; and

an x-y axis controller and a z-axis controller which moves at least one of the nozzle on the table in response to the error signal.

9 . The printer of claim 8 wherein the means for sensing is a nozzle motion sensor and a table motion sensor.

10 . The printer of claim 9 wherein the nozzle motion sensor and the table motion sensor are one of an accelerometer, optical or motion sensor or piezoelectric sensor.

11 . The printer of claim 8 wherein the means for comparing is a controller adapted to provide a closed loop feedback signal to the x-y axis translator and the z-axis translator to minimize relative motion between the nozzle and the table and unwanted positional error in an x-y printing plane.

12 . The printer of claim 8 wherein the x-y axis translator and the z-axis translator are stepper motors.

13 . A three-dimensional printer comprising:

a print head with a motion sensor and a build platform with a motion sensor for monitoring the position of the print head and the build platform;

x-y axis and z-axis translators for the print head and the build platform; and

a closed loop feedback controller adapted to generate signals to the x-y axis translator and the z-y axis translator in response to motion sensor signals to minimize the relative motion between the print head and the build platform and unwanted positional error in an x-y printing plane.

14 . The printer of claim 13 wherein the motion sensor is one of an accelerometer, optical motion sensor or piezoelectric sensor.

15 . The printer of claim 13 wherein the x-y axis and z-y axis translator are stepper motors.

16 . The printer of claim 13 wherein the print head includes a nozzle.

17 . The printer of claim 13 wherein the build platform includes a table.