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Pro/DESKTOPđ Tutorial Kinematic Movements Written by Tim Brotherhood Copyright â 2003, Parametric Technology Corporation (PTC) All rights reserved under copyright laws of the United States and other countries Conditions of use Copying and use of these materials is authorized only in the schools of teachers who attend official training with a PTC certified trainer PTC, the PTC Logo, The Product Development Company, Create Collaborate Control, Simple Powerful Connected, Pro/ENGINEER, Pro/DESKTOP, Wildfire, Windchill, and all PTC product names and logos are trademarks or registered trademarks of PTC and/or its subsidiaries in the United States and in other countries All other product names and marks referenced herein are trademarks or registered trademarks of their respective holders All other use is prohibited unless written permission is obtained from the copyright holder Acknowledgements Sheila Schencke, Executive Director, STARBASE Louisiana Barbara Koscak, Executive Director, STARBASE Michigan Rick Simms, Deputy Director, STARBASE Michigan Feedback In order to ensure these materials are of the highest quality, users are asked to report errors to PTC at schools@ptc.com Suggestions for improvements and other activities would also be very welcome Kinematics T ABLE OF CONTENTS FILES FOR KINEMATICS INTRODUCTION SOLAR PANELS Pro/DESKTOP model Folding the panels Unfolding the panels .8 CONTROL SURFACES ON THE SHUTTLE Pitch 10 Open a Pro/DESKTOP model 10 Elevator movement 11 Roll 11 Aileron movement 12 Yaw 13 Rudder movement 14 SOJOURNER 16 Opening the Pro/DESKTOP Sojourner model 16 Suspension 17 Steering 18 Summary 19 QUIZ 20 QUIZ - ANSWERS 21 Kinematics FILES FOR K INEMATICS The following files will be needed to successfully complete this project: File Name C152 Open Assembly.zip - including Aileron drop link.des Aileron Starboard.des C152 assembly.des Elevator drop link V2.des Elevator.des Frame.des Rudder box.des Rudder link.des Tail.des Yoke horn.des Aileron end.des Aileron tube support.des Cabin side.des Elevator long link.des Firewall.des Fuselage lower.des Rudder cross link.des Rudder pedal.des Vertical stabilizer.des Aileron rear drop link.des Aileron.des Control yoke.des Elevator slide.des Flap.des Fuselage sub assembly.des Rudder front drop pin.des Rudder.des Wind.des Fuselage.des Rudder.des Thruster.des Main engine.des Shuttle assembly.des Font link right.des Rear link right.des Solar panel.des Front link.des Rear link.des Steering mount.des Elevator.gif Pitch.gif Roll.gif Shuttle Assembly.zip - including Cargo bay door.des Port elevon.des Stbd elevon.des Sojourner Assembly zip - including Chassis.des Mid link des Sojourner assembly.des Wheel.des Solar Compartment Assembly.zip - including Link.des Solar compartment.des Solar compartment assembly.des Solar panel.des Unfolding.avi Yaw.gif Kinematics I NTRODUCTION In this tutorial you will explore Pro/DESKTOP models that have moving parts This is called kinematics First, you will explore how solar panels are opened on a space station Next, you will learn how the largest glider in the world, the space shuttle, is controlled for landing Finally, you will be shown how the steering mechanism and suspension system on the Mars explorer, Sojourner can be moved independently to cope with the rugged terrain Kinematics SOLAR P ANELS To generate enough electricity to power their systems, satellites and space stations have solar panel arrays that use photovoltaic cells covering the largest possible surface area During launch the solar panels must be tightly folded When the space station arrives in space the panels are unfolded Folded Open • Using Windows Explorer, locate the file called Unfolding.avi • Double click on the file and it will play in Windows Media Player The animation shows how compact the solar panels are when stowed and the large area they present when deployed Pro/DESKTOP model • Open the file called Solar Compartment Assembly.des The solar panels are already in the open position The next section will show you how to close them Kinematics Folding the panels • Activate, the Select Component tool and click on the panel next to the central compartment to select it • With the mouse point to the left hand edge of the selected panel • Slowly drag the edge of the panel towards the central compartment You will see the panels folding until they are tight together Kinematics • Repeat the process with the other side panels The solar panels are now in the launch position Notice how little space they need when stowed Unfolding the panels This is more difficult because you cannot see the inner panels in order to select them You will learn how to use the Component browser to select the correct component • Change the Workplanes browser to show Components The solar panel closest to the compartment is named Solar panel • Move the mouse over the text in the browser and right mouse click • From the floating menu click on Select Component The solar panel will be selected, with the edges turning red Kinematics • Use the same technique you used before to drag the edge of the solar panel away from the compartment and the solar array will unfold CONTROL SURFACES ON THE SHUTTLE In space, the shuttle uses small rockets to maneuver In the atmosphere, there are control surfaces at the rear of the shuttle much like those on passenger aircraft The control surfaces are colored black on the illustration to make it clear where they are Rudder Elevons (combined elevators and ailerons) On the real shuttle many of the surfaces are black, why you think this is? There are several reasons why they are this color There are three major axes of movement for all aircraft, pitch, role and yaw In the samples folder three animations are provided showing how the control surfaces cause these movements Kinematics Pitch • Locate the file Pitch.gif • Double click on the file The gif animation will open looking like this The control surfaces at the outer rear edges of the wing will move up making the rear of the shuttle move down and the nose to pitch up Next the elevators will move down causing the rear of the wing to rise pitching the nose down The animation will repeat until you close the browser window What have you learned from this? Elevators control the Pitch of an aircraft Open a Pro/DESKTOP model • Open the file called Shuttle assembly.des The model is an assembly made up of several parts The control surfaces are components in the assembly and can be moved by selecting one and dragging on screen • Use the cursor keys on the keyboard to turn the model to this position Kinematics 10 Elevator movement • Activate , the Select part tool in the selection toolbar • Move the mouse over the port (left) elevator until the edges pre-highlight in blue • Click with the left mouse button on the elevator to select it The edges of the port elevator will be highlighted in red to show it is selected • Move the mouse cursor over the rear edge of the elevator • Hold down the left mouse button and drag upwards a short distance • Release the mouse button The elevator will now be in the up position • Repeat the previous steps to move the starboard (right) elevator to the up position In this position the elevons are acting as elevators forcing the rear of the shuttle down and making the shuttle nose pitch up Roll • Locate the file Roll.gif • Double click on the file The gif file will open looking like this and animate showing how the control surfaces cause roll Kinematics 11 The same control surfaces that made the shuttle change pitch control the shuttle in roll, this time acting as ailerons As the left aileron moves up the right aileron moves down This makes the shuttle roll to the left When the ailerons are reversed the shuttle rolls to the right The animation will repeat until you close the browser window What have you learned from this? Ailerons control the roll of an aircraft Aileron movement Return to the Pro/DESKTOP screen Both elevons should still be in the up position showing how they move as elevators You will now position the elevons as ailerons to make the shuttle roll • Using the cursor keys on the keyboard rotate the shuttle to this position • Move the mouse cursor over the starboard aileron The edges will turn blue • Click with the left mouse button to select the aileron Kinematics 12 • The edges of the aileron will be highlighted in red to show it is selected • Move the mouse cursor over the rear edge of the aileron • Hold down the left mouse button and drag the aileron downwards a short distance • Release the mouse button The aileron will now be in the down position In this position the elevons are acting as ailerons forcing the shuttle to roll Which way will the shuttle roll? Roll to starboard? Roll to port? Yaw • Locate the file Yaw.gif • Double click on the file The gif file will open looking like this and animate showing how the control surfaces cause yaw Kinematics 13 The rudder is the moving part of the vertical stabilizer and makes the shuttle change direction in yaw As the rudder moves to the left, as you look from the rear the shuttle the nose will yaw to the left When the rudder moves across to the right the shuttle nose will yaw to the right The animation will repeat until you close the browser window What have you learned from this? The rudder controls the yaw of an aircraft Rudder movement Return to the Pro/DESKTOP screen The rudder should be in the central position You will position it to make the shuttle yaw • Using the cursor keys on the keyboard rotate the shuttle to this position • Move the mouse cursor over the starboard rudder The edges will turn blue • Click with the left mouse button to select the rudder Kinematics 14 • The edges of the rudder will be highlighted in red to show it is selected • Move the mouse cursor over the rear edge of the rudder • Hold down the left mouse button and drag the rudder to the left a short distance • Release the mouse button The rudder will now be pointing to the left This would cause the shuttle nose to yaw to the left • Use the same method to move the rudder to the right On the shuttle in flight this would cause the nose to yaw to the right The rudder on the actual shuttle performs two functions It is split vertically Once the shuttle has touched down the two halves open to act as an airbrake Kinematics 15 SOJOURNER On July 6th 1997 The Mars rover called Sojourner rolled down a ramp from the Mars lander to begin exploring the surface of the red planet This section of this tutorial shows you how the suspension and steering of Sojourner allows it to travel over the rocky terrain Web links There are several Internet sites with information on the Mars explorer and Sojourner These have lots of images, videos and 3D VRML where you can find out lots more about the rover http://mars.jpl.nasa.gov/mer/ www.btinternet.com/~reg.joy/Projects.htm http://mars.jpl.nasa.gov/MPF/vrml/vrml.html Opening the Pro/DESKTOP Sojourner model • Locate the samples folder for the STARBASE materials • Open the file called Sojourner Assembly.des in Pro/DESKTOP The model is an assembly of chassis, suspension components and wheels The chassis has been fixed so that you can select and drag the other parts to explore how the suspension and steering operates Kinematics 16 Suspension • Use , the Select Component tool to highlight the center wheel support • Drag the end of the support upwards to position the center wheel as if it is resting on a bump or rock • Select the front suspension arm • Move this to show the raised position for the wheel Kinematics 17 The suspension on Sojourner provides a large vertical movement to cope with sloping ground and large rocks The news reports at the time the lander was operating showed Sojourner with one wheel high up against a large rock the scientists nicknamed ‘Yogi’ Steering Each wheel on Sojourner is moved by a small electric motor By rotating each wheel independently the rover can move in many different ways • Select the front steering support • Drag the support until the wheel is pointing like this • Repeat the steps to position the other corner wheels like this Which direction you think the rover will move? Kinematics 18 • Change the steering arms to these positions Which direction you think the rover move now? This position is one of the more unusual It is called crabbing If only cars could this, parking would be so much easier! Summary In this tutorial you have learned how the components in Pro/DESKTOP models can be repositioned to show how mechanisms work Why you think this is useful? NASA spends huge amounts of money developing equipment to launch into space The demands of space travel often require that components be made from very expensive materials using costly processes Designs are developed using computer aided design software and tested on computers to find and fix problems and faults This avoids many expensive mistakes when the parts are being made and assemblies put together Kinematics 19 Q UIZ Why are solar panels folded for launch? In Pro/DESKTOP, how are components selected when the part cannot easily be seen? What are the two functions elevons perform? Match the direction of movement to the controls (Draw a line between the movement and the correct controls) Pitch Roll Yaw Rudder Elevators Ailerons How many wheels are there on Sojourner? How many of the wheels on Sojourner can turn for steering? Which year did Sojourner start exploring the surface of Mars? Why does Sojourner have suspension that moves through large distances? What is special about the steering on Sojourner? 10 What is the benefit of using computer aided design software and computers to design space equipment? Kinematics 20 Q UIZ - ANSWERS Why are solar panels folded for launch? They must fit inside the launch rocket In Pro/DESKTOP, how are components selected when the part cannot easily be seen? Right click on the component name in the Component browser and click on Select Component What are the two functions elevons perform? Moving up and down together they work as elevators and as ailerons when they move in opposite directions Match the direction of movement to the controls (Draw a line between the movement and the correct controls) Pitch Roll Yaw Rudder Elevators Ailerons How many wheels are there on Sojourner? Six How many of the wheels on Sojourner can turn for steering? Four Which year did Sojourner start exploring the surface of Mars? 1997 Why does Sojourner have suspension that moves through large distances? To allow Sojourner to ride over the bumps and large rocks on the surface of Mars What is special about the steering on Sojourner? All four corner wheels can be turned independently 10 What is the benefit of using computer aided design software and computers to design space equipment? To avoid expensive mistakes at the stage of making parts and assembling the end product Kinematics 21 ... Suggestions for improvements and other activities would also be very welcome Kinematics T ABLE OF CONTENTS FILES FOR KINEMATICS INTRODUCTION SOLAR PANELS ... Solar panel.des Unfolding.avi Yaw.gif Kinematics I NTRODUCTION In this tutorial you will explore Pro/DESKTOP models that have moving parts This is called kinematics First, you will explore how... 18 Summary 19 QUIZ 20 QUIZ - ANSWERS 21 Kinematics FILES FOR K INEMATICS The following files will be needed to successfully complete this