Application of Tele-controlHiroto Kato, Satoshi Ueki, Akihiro KaneshigeToyota national College of TechnologyThank you, Mr ***

Today, im going to give a presentation under the title of Application of tele-control.

1OutlineBackgroundControl systemMasterSlaveBlock diagramExperimental resultReaction forceOverhead tele-controlSummary

The organization of my presentation is as follows.

2Background of this researchTele-control is an effective method for operating in hazardous environment and for remote operation. There are many way of application, such as followings.

By combining tele-transport control system which has different shape Master/Slave system, it is expected to extend the range of application.

Robot arm in the spaceJAXA HP: http://rexj.web.fc2.com/RJ/rex4.htmlRemote operation using da vinciengadget HP:http://japanese.engadget.com/2009/04/09/da-vinci/

To begin with, I will provide background information of this research.such as Robot arm in the space and Remote surgical operation.

3Background of this researchOverhead craneIt is the one of the most useful transport systems, because it is simple and it can cover a wide working area.BesidesThere are many accidents caused by human errors.An expert operator is indispensable to control an overhead crane.

It is expected to control overhead crane from remote place safely and easily.

Overhead crane (Toyohashi University of Technology)Have you ever seen Overhead crane?Besides There are many accidents caused by human errors.An expert operator is indispensable to control overhead crane.

For these reasons,

4The purpose of this researchWe configure a remote transportation system for an overhead crane using the internet as a communication line.The transport system shall be easy-controlled system for operators.

Cooperation with such a transport system will provide many application of tele-operation.

So in this research,

5Essential elements for overhead crane tele-control systemStability Time delays on the internet causes serious problem with stabilizing the control system.The design method Miyoshi* proposed for stabilizing tele-control system is adopted.

Ease of use of the transport systemDifficulties of controlling overhead crane are often caused by swing of the transferred object.We configure a transport system which an operator can feel the swing of the rod instinctively.*T. Miyoshi, K. Terashima, and M. Buss, 2006, A Design Method of Wave Filter for Stabilizing Non-Passive Operation System, pp. 1318-1324, IEEE Int. Conf. on Control Applications.

Next, im going to talk about Essential elements for this system.

There are 2 important things in this system.The stability

Ease of use

6Overhead crane tele-control systemWithout swingMasterSlaveInternet and a controllerWith swing7Master arm1 degree of freedom arm shown is used as a Master. The arm is only able to rotate.

ArmStrain gage: observe the strain value of the arm

Motor driver and strain ampEncoder: observe the angle of the armThis is a picture of Master arm.This arm attached to the motor is able to rotate and this encoder detects the angle of the arm.The motor is used to generate reaction force of Slave. We observe the reaction force with this straingage.8Overhead crane (Slave)Slave is an automatic overhead crane system which transfers an object with the cart that can move in the direction of X. The swing angle of the rod is measured by a laser sensor fitted to the table of the cart.

CartRodObjectLaser sensor

RodSlave is an automatic overhead crane system shown in this picture.The swing of the object is measured by laser sensor.

We configured Tele-conrol transport system with this Master/Slave.9Block diagram of the control systemThe stability of this system is verified according to small gain theory.

Tele-operator sideOperator sideInternetPhase-lead compensatorWave filter10Tele-control experimentCondition of the experimentsThe experiment was held between Toyota National College of Technology (T.N.C.T) and Toyohashi University of Technology (T.U.T) using internet. There is a straight-line distance of approximately 50 km.Time delays during the experiments were around 40ms.

The purpose of the experimentsWe confirm following 2 aspects through the experiments.(1) The operator feels the swing of the rod as a reaction force.(2) The crane is controlled according to operators order.

First, (1)Second, (2)11Reaction force by the swingMethod to verify the reaction forceMake the transferred object swing by eternal force.SlaveFasten the end of the arm by grasping it with human hands.MasterOperatorArmObjectCraneExternal forceWe did the following experiment to see if an operator can feel the swing of the rod.

The operator gripped the arm. In Slave side, an external force was applied to the object to make it swing.12Reaction force by the swingThe reaction force changed depending on the weights of the operators arm and force adjustment. The reaction force with the same frequency as the swing was made in the Master.

Reaction forceSwing of the rodThis graph shows the swing of the rod.

This graph shows the reaction force on the arm.13Overhead crane tele-controlExperimentThe operator tried to transfer the object to a distance of 1.3m from the start point. The operator watched the web camera and checked how the overhead crane moved while he operated overhead crane.

In this experiment, we see how the crane is controlled.14Overhead crane tele-controlThere are delays which depends on the communication line between the ordered speed and the crane speed, however, The cart of the overhead crane moved at almost the same speed as the operator ordered.

Speed orderCrane speedVerification of speed control

This graph shows comparison between speed order and crane speed.

15Verification of performancePosition of the object

Swing angle of the rodThe operator was able to transfer the object on the target place.1.3This shows the position of object during the experiment.

And this shows the swing angle of the rod.16SummaryWe designed an overhead crane tele-operation control system that can use the internet for communication.The system can be speed controlled by a remote operator and bring the swing of rod as a reaction force to the Master.

These findings were proved by the demonstration between T.U.T and T.N.C.T. By using transport tele-control system, we expect to be able to extend the use of telecontrol.In this research,,,

Thank you very much for your kind attention.17AcknowledgementThe author would like to thank Prof. Dr.-Eng. Martin Buss of Technical University Munich for his cooperation.

Verification of communicationFirst, we checked the condition of the network as following.T.N.C.TT.U.T1. Send a triangle data to T.U.T 2. Receive the triangle data 3. Return the data 4. Receive the data andcompare with the data of step 1. InternetVerification of communicationTriangle data

Time delay

Communication seems to go smoothly, since the shape of both the sent and received triangle data is almost the same.

There are constant time delays of approximately 40ms.

Sending dataReceiving dataTransfer function of Master+-The block diagram of MasterTransfer function of Slave

Phase lead compensator

Verification of stabilityThe amplitude ratio exceed 0 and the gain exceed 1 around7 rad/sWave filterThe gain doesnt exceed 1 and the system becomes sable