Development of Experimental Set Up for the test and validation of the failure recovery technique

[NEEHAR]

LabVC   Contact Information:

University: Texas A&MUniversity, College Station

Team Member(s): AnuragTolety, Phani Neehar Kapila Bala

Faculty Advisors: Dr. NinaRobson

Email Address: kbpneehar@neo.tamu.edu

Project Information

Title: Development of anExperimental Set Up for Testing and Validation of a Novel Robot Arm JointFailure Recovery Technique

Description:

A novel failure recovery technique was formulated byRobson and McCarthy. This technique says that whenever there is a joint failurein robot manipulators, the base of robot arm and wrist point of the robot armcan be repositioned so that the task is achieved despite the failure of one ofthe joints.

We developed an experimental set up for testing thisjoint failure recovery technique. The experimental set up consists of a Fivedegree of freedom robot arm and a mobile platform which are controlled by NIsbRIO 9632XT using LabVIEW.

Mathematica calculates the repositioning coordinatesand with the help of LabVIEW, the robot arm is repositioned.

Products:

NI sbRIO 9632XT real-time controller

The Challenge:

The challenge was to simultaneously control the robotarm and platform like a Mars Rover to go to the required position, to demonstratethe failure recovery capability in case of Elbow joint failure.

The Solution:

The project works on LabVIEW 2010, LabVIEW FPGA,LabVIEW Real Time, with the NI sbRIO 9632XT controller. It has three levelarchitecture, the top level takes signals from the laptop to control theplatform and the middle level transfers this signals to the real timecontroller, the third level takes these signals from the real time controllerto the FPGA pins.

The benefits are mainly simplicity in connecting to several hardware devicesand sensors, intuitive logic in designing the programs for execution of threelevel architecture, biggest advantage is the graphic development platform of  LabVIEW 2010.

Pictures for this Project:

Figure 1. The Robot arm and Platform developed in our lab

This picture talks about how we integrated the robotarm and platform in our lab, the platform used is a SMP platform and the arm isLynxmotion (AL5D) robot arm.

Figure 2. The casing designed to incorporate the NI sbRIO 9632xt realtime controller, Power system: Includes 12V Battery Pack to DC motors,  supply power to RIO (24V) through a regulatorand to power the servos of the arm, Router and 9V battery to power robot arm.

Figure 3. Architecture for the control of Robot arm and Platform, withtop level as Laptop level, middle level as Real time controller level and thethird level as FPGA level with the SSC 32 control.

Figure 4. Block Diagram of the Top level implementation: Collectingsignals from arrow keys of the laptop to send it to the middle level throughthe shared variables

Figure 5. Front Panel of the Top level implementation

Figure 6. Block Diagram of the middle level implementation to transferthe signals from the Top level to the FPGA level through shared variables

The FPGA level typically does the timingfor the loop, the timing is decided by the Period1 variable, the signal at thechannel A01 is kept high for a certain amount of time equal to Period1 toaccept the inputs from the middle level, then the signal is made low, this isrepeated in a cycle.

The VIs for the Robot arm:

There is only one VI for controlling therobot arm, the signals are formed from the movement of the joystick, thesesignals are checked to say whether they lie within the joint limits, if thesignals lie within the joint limits, then the signals are transferred to theSSC 32 controller to activate the required servos at different joints. Thefront panel for the control of Robot arm is given below:

Figure 7. The Front Panel for the control of Robot arm

The pictures below show the Elbow failure demonstratedat our laboratory:

The first picture shows a healthy arm and the nextpicture shows a faulty arm, the pictures show that the arm and platform arerepositioned in each case.

Figure 8. The healthy arm- TRT serial chain mounted on SMP

Figure 9. The T-T robot arm with the elbow failure

VIDEO: The uploaded video inthe application at the URL: http://www.youtube.com/watch?v=IwlrhIzeAn4

Shows the experimental set upwhich we built up in our lab, the robot arm (AL5D) is mounted on the SMPplatform which is controlled by NI sbRIO 9632XT through LabVIEW 2010.

The first part of the videountil 0:36 secs shows the healthy arm to reach the task and the next part showsthe arm with the elbow failure able to complete the task even with the failuresin the elbow joint.

[LPS]

Hello there,

Thank you so much for your project submission into the NI LabVIEW Student Design Competition. It's great to see your enthusiasm for NI LabVIEW! Make sure you share your project URL with your peers and faculty so you can collect votes for your project and win. Collecting the most "likes" gives you the opportunity to win cash prizes for your project submission. If you or your friends have any questions about how to go about "voting" for your project, tell them to read this brief document (https://forums.ni.com/t5/Student-Projects/How-to-Vote-for-LabVIEW-Student-Design-Projects-doc/ta-p/3...). You have until July 15, 2011 to collect votes!

I'm curious to know, what's your favorite part about using LabVIEW and how did you hear about the competition? Great work!!

Good Luck, Liz in Austin, TX.

[cacalderon]

Hello Phani Neehar

I was reviewing your project Development of Experimental Set Up for the test and validation of the failure recovery technique.

Link: https://decibel.ni.com/content/docs/DOC-16497

I'm interested in using the "Inverse Kine AL5D and SMP.vi" program, however it is not available in this link the program "Create AL5D and SMP.vi"

Please, you could share or send it to my mail cacalderon@utpl.edu.ec.

Thanks