poster ZhongZhe - Robotics Institute Summer Scholars...
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Interfacing with ROS Integration of a Cartesian Robot with ROS Zhong Zhe, Ankit Bhatia and Matt Mason The Manipulation Lab, Robotics Institute • A Cartesian Robot is an industrial robot whose three principal axes of control are linear and are at right angles to each other. The three sliding joints correspond to moving the wrist updown, inout, backforth. • A popular application for this type of robot is a computer numerical control machine an 3D printing. Pick and place machines and plotters are also based on the principal of cartesian robot. • Goals: Cartesian Robot Introduction Results • The Robot Operating System (ROS) is a flexible framework for writing robot software. It is a collection of tools, libraries, and conventions that aim to simplify the task of creating complex and robust robot behavior across a wide variety of robotic platforms. Hardware and Controls Future Work Just a part of work has being completed this summer and one simple application is used in drawing machines where a pen translates across an x-y plane while a tool is raised and lowered onto a surface to create a precise design. It can also be used in 3D printer design but it is harder. Another future direction is to use ethernet instead of RS232 to command the robot(TCP/IP). This will allow us to log information faster and command the robot at a higher frequency. 6k4 motion controller • 6k4 motion Controller • Linear servo motor driver • Rotary Encoder • Brakes • Limit&Home Sensors • Couplings • PC based machine control Driver ROS Computer Robot Services Input Feedback Output Operating Principle of ROS Connection with Robot Commands • Procedure • Create ROS environment and create catkin workplace • Write ROS services • Test services on the robot and debug them • Actuate robot using ROS services • set position, velocity, acceleration, deceleration of robot • get position of encoder and status of the robot motion controller • Robot Accuracy(position error) is the robot's ability to position its wrist end at a desired target point within the work volume, and it is defined in terms of spatial resolution. • Procedure • The following graph is the error bar of each axis: xaxis: maximum error is 0.0009 inch mean errors is 0.0004 inch standard deviation is 0.00024 inch yaxis: maximum error of is 0.0008 inch mean error is 0.00036 inch standard deviation is 0.0003 inch • collect 5 groups of coordinate data of each axis • calculate the mean errors of each axis using • Set up robot • Write driver for the robot • Measure position errors of xaxis and yaxis Computer Motion Controller X-axis Motor Drive Z-axis Motor Drive Y-axis Motor Drive Rotary Encoder Rotary Encoder Rotary Encoder Feedback • This flow chart is how the ROS driver works Commanded XAxis(in) Commanded YAxis(in) Measured XAxis(in) Measured YAxis(in)
Transcript of poster ZhongZhe - Robotics Institute Summer Scholars...
Interfacing with ROS
•Set up robot •Write ROS services and debug •Test and measure errors of x-‐axis, y-‐axis and z-‐axis
Integration of a Cartesian Robot with ROSZhong Zhe, Ankit Bhatia and Matt Mason The Manipulation Lab, Robotics Institute
• A Cartesian Robot is an industrial robot whose three principal axes of control are linear and are at right angles to each other. The three sliding joints correspond to moving the wrist up-‐down, in-‐out, back-‐forth.
• A popular application for this type of robot is a computer numerical control machine an 3D printing. Pick and place machines and plotters are also based on the principal of cartesian robot.
• Goals:
Cartesian Robot
Introduction Results
• The Robot Operating System (ROS) is a flexible framework for writing robot software. It is a collection of tools, libraries, and conventions that aim to simplify the task of creating complex and robust robot behavior across a wide variety of robotic platforms.
Hardware and Controls
Future Work
Just a part of work has being completed this summer and one simple application is used in drawing machines where a pen translates across an x-y plane while a tool is raised and lowered onto a surface to create a precise design. It can also be used in 3D printer design but it is harder. Another future direction is to use ethernet instead of RS232 to command the robot(TCP/IP). This will allow us to log information faster and command the robot at a higher frequency.
6k4 motion controller
• 6k4 motion Controller • Linear servo motor driver • Rotary Encoder • Brakes • Limit&Home Sensors • Couplings
• PC based machine control
Driver ROSComputer
Robot
Services Input
Feedback Output
Operating Principle of ROS Connection with Robot
Commands
• Procedure
• Create ROS environment and create catkin workplace • Write ROS services
• Test services on the robot and debug them • Actuate robot using ROS services
•set position, velocity, acceleration, deceleration of robot •get position of encoder and status of the robot motion controller
• Robot Accuracy(position error) is the robot's ability to position its wrist end at a desired target point within the work volume, and it is defined in terms of spatial resolution.
• Procedure
• The following graph is the error bar of each axis: x-‐axis: maximum error is -‐0.0009 inch mean errors is -‐0.0004 inch standard deviation is 0.00024 inch y-‐axis: maximum error of is -‐0.0008 inch mean error is -‐0.00036 inch standard deviation is 0.0003 inch
•collect 5 groups of coordinate data of each axis •calculate the mean errors of each axis using •Set up robot
•Write driver for the robot •Measure position errors of x-‐axis and y-‐axis
Computer Motion Controller
X-axisMotor Drive
Z-axisMotor DriveY-axisMotor Drive
Rotary EncoderRotary EncoderRotary Encoder
Feedback
• This flow chart is how the ROS driver works
Commanded X-‐Axis(in)
Commanded Y-‐Axis(in)
Measured X-‐Axis(in)
Measured Y-‐Axis(in)
