Mini Racer Competition.

Transcription

1 Mini Racer Competition. Introduction This Module provides the rules and different levels of competition for the Mini Racer. It also provides a solid model of the track and a sample car along with instructions on how to set up the constraints and apply gravity to race the cars within the Solidworks software. The step by step instructions will take you through detailed steps in creating a more advanced animation in motion study. The animation will be known as the MiniRacerProject SLDASM. Figure 1 displays what the MiniRacerProject SLDASM should look like at the completion of this lesson. Referenced illustrations will be used to help explain certain processes and to compare results. The concepts taught in this lesson present the knowledge required to create a motion analysis and edit the properties of friction and gravity. Figure 1

2 . Mini Racer Project Objectives The objective of this project is to introduce the student to the complete process of designing, optimizing the design and testing it digitally using Solidwork software. The student will have the opportunity to pull the acceleration, speed and time information from the Solidworks Motion Analysis. The student will have the opportunity to 3D print the Mini Racer and compete in a physical race using a 16 foot Hot Wheels track. The solid model of the track that is shown in Figure 1 and the actual solid model file is attached to this document. There are four different levels of completion. The first being the most basic, designing the car, 3D Printing it and racing it. The more advanced competitions levels are listed below. Level 1: Design, test, 3D print and assemble the fastest car. This car will be raced in heats of six on a Hot Wheels track that is 16 feet long. The start will be four feet at a 45 degree angle. The remaining 12 feet will be flat. Reference the attached solid model of the Hot Wheels Track Recourses: There will be training files on creating basic cars and basic assemblies currently not available. Also we will have a library of cars to choose from. For Mini Racer Design ideas reference Figure 2. Level 2: In addition to this submit your complete car assembly digitally as a zipped compressed file. One week prior to the competition. These cars will be loaded into the Solidworks Track Assembly to digitally compete with the competition. Recourses: Reference the step by step instruction in this module for instructions how to complete the assembly, apply gravity and create the required acceleration, speed and time charts from Solidworks. Level 3: In addition to Level 1 and Level 2 submit the Solidworks generated charts for acceleration, top speed and total time to complete the provided track. Recourses: There will be training files and PDF on how to extract this information from Solidworks. Level 4: In addition to Levels 1, 2 & 3 submit your hand calculated acceleration, top speed and completion time for the provided track. Compare the results of the hand calculations and the digital (Solidworks) results. Discuss if there is a difference and the possible reasons for the differences. Recourses: There will be training files and PDF on how to compete the math by hand. There will be an example document for a basic comparison between the two sets of results as well as how to present the information. Mini Racer size Maximum specifications (reference Figure 2 for Mini Racer examples) Width = 1.2" Length= 3.7" Height= 2.0"

3 Mini Racer Project. All Mini Racer components are required to be 3D Printed plastic except for the axel: Body: The body can be designed, scanned or borrowed from and existing model (as long as copyright is not violated). Wheels: (There is no limit to the number of wheels or size of wheels, one wheel or as many as you want to fit into the size limitation. Accessories: air foil, mirrors etc. are optional. Stickers and/or Custom Paint Job: You are encouraged to customize your design, use your artistic ability. Set your car apart by having the best looking Mini Racer. The axels do not need to be 3D printed. The axels and how you attach the wheels is up Figure 2

4 . Mini Racer Project Step by Step Instructions Creating a Motion Analysis and Using Some of the Tools Motion Analysis Provides In this section you will have the opportunity to learn how to create a Motion Analysis of your assembly. When you complete all of the steps in this lesson, the result should look similar to the picture shown in Figure 1. 1 Start Solidworks Figure 3 Select the down arrow then select the New Option to start a Solidworks part. Start Solidworks. From the Desktop, double click on the Solidworks icon. If a short cut does not exist on the desktop, you will need to click on Start, Programs, and locate the Solidworks program. Double click on the Solidworks icon. Be patient, it may take a few moments to bring up the Solidworks.

5 Mini Racer Project. 2 Start a New Assembly File (document) Start a New Document. Select the New Option as shown in Figure 3. This will bring up window similar to what is shown in Figure 4. 3 Select The Assembly Option. Figure 4 Double click this or select and then select OK Select the Assembly icon. To do this you need to double click on the assembly icon as shown in Figure 4. You can also select the assembly icon and then select the OK button in the bottom right of the window. This will bring up the Assembly Manager Environment as shown in Figure 5.

6 . Mini Racer Project Figure 5 Default Name for the newly created Assembly Status Bar displays the current environment Editing Assembly Click the Browse button 4.0 Insert Parts for the Assembly and Mate Them Together 4.1 Navigate to the file where the parts are stored. To do this you will need to click on the browse button as shown in figure 5. Then you will go to the folder where you have saved the files for this project. 4.2 Insert Necessary Parts For Assembly. Insert the following parts into the Assembly: 1 Race Track, and 1 Mini Racer. Your screen should look like figure 6.

7 Mini Racer Project. Figure Assemble the Components 5.1 Mate the Assembly Together. To assemble the components together you will have to make 4 tangent mates (1 for each wheel under the car). Figure 7 below shows what to do in greater detail. To create a tangent mate, first click the mate button. On the left-side of your screen the Mate box appears, click on the button that says Tangent now select your surfaces and click the green check mark. Once finished compare your screen to figure 8. Figure 7 Tangent mate the four black tires onto the top of the race track

8 . Mini Racer Project Figure 8 6 Enter Motion Study and Unlock Motion Analysis 6.1 Enter Motion Study. Move your cursor to the bottom left portion of your screen and click on the Motion Study 1 tab. 6.2 Unlock Motion Analysis. Move your cursor to the arrow next to the word Solidworks in the top left portion of your screen. This will bring out the menu bar, click on Tools, then towards the bottom of the menu you will find Add-ins, left click it and it will bring up a box like the one in figure 9. Click on the boxes Solidworks Motion and Solidworks Simulation. Then click OK. Figure 9 Select these boxes

9 Mini Racer Project. 6.3 Entering Motion Analysis. Move to area on your screen shown in figure 10. Left click the arrow then move down and select Motion Analysis. Now you are ready to create an analysis. Figure 8 Left click 7.0 Suppressing Mates, Inserting Gravity, and Contact. 7.1 Suppress both Tangent Mates. In the animation tree click on the plus sign next to the word Mates. The 4 mates you created should be visible below. Right click over one of the four tire tangent mates, and then left click suppress, now do the same for the other tangent mates. 7.2 Insert Gravity. Above the time bar left-click the gravity icon. This will bring up the gravity manager on the left of your screen. As shown in figure 11 select the Y box under gravity parameters. Make sure the green arrow in the bottom right corner of your screen is pointing down and click the green check mark.

10 . Mini Racer Project Figure 9 Select the Y box 7.3 Inserting Contact between the Car and Track. Above the time bar and next to the gravity icon, left-click the contact button. The contact properties manager will appear on the right. Left- click the car and the track from the pull tree in order to select the entire car and track. They should turn blue like in figure 12 then click the green check-mark (you will be coming back to edit some of the properties later.) Figure 10 Select the Miniracer and track from the tree, NOT from the simulation

11 Mini Racer Project. 8.0 Creating a Simulation and Editing Properties 8.1 Calculating a Simulation. To reposition your car, click and drag to move it in front as shown in figure 13. Click the calculate button. A simulation should automatically generate in which the car slides down the track and stops near the end of the track. Figure 11 Left click calculate button Note: Every time you edit something in motion analysis you have to click the calculate button for the changes to appear in the animation. 8.2 Editing Friction Properties. We can edit the friction and gravity options of the simulation in order to change how far the car moves along the track. In your animation tree find and right-click Solid Body Contact 1 then left click Edit Feature. This should bring up the contact properties manager again. First, unselect the material box, now you can try entering various numbers in the boxes, be sure to recalculate so that the program updates the simulation. One combination is shown in figure 14

12 . Mini Racer Project Figure 12 Enter these numbers into the appropriate slots. (Requires static friction box to be unselected) 8.3 Change the Gravity. In order to change the gravity, right click on gravity in the animation tree, and left click edit feature. In the box shown in figure 15 enter 64.1in/s^2 (gravity on the moon). Then click the green check mark and recalculate. It should run the same just slower (if the animation doesn t finish go to the time-bar, click and drag the top black diamond to 6 sec.). To change the gravity back to Earth s open back up edit feature click the button the button shown in figure 15 to reset it exit and recalculate. Figure 13 Resets gravity to Earth s Enter Moon s Gravity 64.1in/s^2

13 Mini Racer Project. Summary The information was covered in a very basic level so nothing would be over looked. The lessons do build on each other. The steps and tools covered in this lesson are now expected to be common knowledge and will not be covered in detail again. Solidworks provides many different options to completing the same task (too many to cover in this lesson). You are encouraged to try some of the alternative and/or optional tools not covered in this lesson.