Designing of Ballon Driven car
Air power has been harnessed for centuries to power the sails of boats or create the mechanical motion of a windmill.
In this project, you will harness the power of air captured in a balloon to power a 3D printed car you are going to design and print.
In this project you will:
- Design a body for your 3D printed car.
- Create a path for air to exit the balloon in a way that will power your car.
- Create wheels and axles for your car to roll on.
Let’s get started!
Step 1: Car Body Design
The body of the car is the main shape of the project.
The body will tell us where the axles and wheels will be positioned, and it will have the balloon connector on it, so we will begin here.
- Place a box on the work plane and size it to be 20mm wide, 60mm long, and 20mm tall.
Step 2: Add Holes for the Axles
We need to create openings for the axles to run through the car.
After we add the axles, we can attach wheels to them.
- Place a cylinder on the work plane and size it to 11mm in diameter and 25mm tall.
- Change the cylinder to a hole.
Step 3: Align the First Axle
We can now position the axle so it will make a hole through the body that we can slide the first axle through.
- Rotate the cylinder 90° so the long direction crosses long ways through the body.
- Select the box and cylinder and align them to the bottom of the box, the end of the box, and the center of the box. Tip: See the image above to see where the hole should be positioned.
Step 4: Position the First Axle
We now have the axle aligned with the body, but it is right at the edge of the box.
We need to position it just a little to make it a bit stronger.
- Rotate your view to look at the model from the side.
- Select the cylinder and press the left arrow key on the keyboard 5 times. This will move the hole 5mm to the left away from the end of the box.
With the cylinder still selected use the black arrow on top to lift the cylinder up away from the work plane 3mm.
Step 5: Create and Align the Second Axle
We can now use the cylinder hole we just created to make a second one that we can position at the other end of the car.
- Duplicate the first axle hole by selecting the Duplicate button on the toolbar.
- Change the snap grid to 5mm.
- Rotate the view to look at the car from the side and press the left arrow 8 times to move the second axle to the opposite end of the car. This will move the second axle 40mm from the first. (8 arrow presses x 5mm movement with each press = 40mm)
Select all the shapes and group them into a single item.
Step 6: Make Your Car More Aerodynamic
You don’t see too many square cars on the road for a good reason. Square shapes have a hard time moving through the air.
Let’s streamline your car making it a little more aerodynamic.
- Place a wedge shape on the work plane and size it to be 5mm tall, 20mm wide, and 40mm long.
- Change the wedge to a hole
Step 7: Position the Wedge Shape
Next, we will position the wedge to remove some material from the car to make it more aerodynamic.
- Rotate the wedge 180° so the flat face that is on the work plane is facing upwards.
- Select the car body and the wedge and align them to the maximum on the left, to the maximum toward the top of the car, and to the center width-wise. Tip: See the image for a specific position.
- Select both shapes and group them into a single item.
Step 8: Add a Nose Wedge to the Car
To complete the aerodynamics work we will add a wedge shape to the form of the car to make it pointier in the front.
- Place a wedge shape on the work plane and size it to 20mm wide, 10mm long, and 15mm tall.
- Rotate the wedge 90° counterclockwise on the Work plane.
- Select both shapes and align them to the center of the car width-wise.
- Let the snap grid to 1 and use the arrow keys to position the wedge at the front of the car. Tip: The snap grid can be changed in the lower right corner of the graphics window.
Select both shapes and group them into a single item.
We have now completed the first part of the design which is the body of a car. Now we make the remaining design of the car such as a balloon connector.
Now we’re going to make a balloon connector, it will be important to know what size balloon is available for this project
Step 1: Create the Balloon Connector
As we create the connector you will want to make sure you adjust sizes to make sure the connector works with the balloons you will be using for your car.
The opening in the balloons I am using is 18mm, so I am making the connector stem 20mm with a 3mm lip to hold the balloon on the car.
- Place a cylinder on the work plane and size it to 20mm in diameter and 10mm tall.
- Place a second cylinder on the work plane and size it to 23mm in diameter and 3mm tall.
- Select both cylinders and align them vertically, then align them to the top.
With both cylinders selected group them into a single object.
Step 2: Add and Angle under the Lip
If we were to print the balloon connector part now, without the purple shape shown in the image below, we would run into a problem with the 3D print, because of the overhang on the lip you will find that the plastic will droop or the print will fail unless you add support for the lip.
In order to help with 3D printing, we will add a small angle (using an upside-down cone) to the bottom side of the balloon connector lip. This will allow the print to continue and slowly expand to the diameter of the lip
Step 3: Create a Hole in the Connector
The last step before positioning the connector on the car is to create an opening in the connector for the air to pass through. We will make the hole in the connector larger than the path in the car just in case the path isn’t aligned just perfectly.
- Place a cylinder on the work plane and size it to 15mm in diameter and 15mm tall.
- Change the cylinder to hole.
- Select both shapes and align them vertically.
- Group both shapes into a single item to cut the hole through the connector.
Now we have done with the balloon connector
Create a Path for the Air
Before we complete the body, we will create a path for the air to exit the balloon and be directed out the back of the car.
The air channel must start somewhere inside the balloon connector since this is where the air will be coming from. The air channel can end where ever you think will provide your car the best boost.
While building the air channel it will help to know a couple of tricks. You can make the body transparent and lock it so it is not selectable (this can be toggled anytime). Doing this will allow you to better position the air channel inside the body.
- In the Shapes, panel drop-down select Community Shape Generators.
- Locate the Purple Bent Pipe shape and drag the shape to the work plane.
- While this shape is selected you will see a number of settings that can be changed in the Inspector panel.
- Set the Outer Pipe Width to 3mm.
- Now use the sliders for the other settings to adjust the other settings to create an air-channel that creates a path from the back of the car to the balloon connector.
- When you are happy with your air channel design select the shapes that make the channel and group them together.
- NOTE: Make sure there is a clear path through the channel for the air to escape.
- NOTE: Make sure the air channel doesn’t break through to the axle opening or all the air will escape into the axle and your car will not move forward.
- Set the air channel shape to be a hole.
- Select the body and the air channel and group them into a single item.
Create Wheels and Axles
Now we’re going to make our car move!
Step 1: Create Wheels for Your Car
The car body looks beautiful now, but without wheels, your car isn’t going anywhere. Let’s get that taken care of by creating some wheels for your car.
- Place a cylinder on the work plane and size it to 20mm in diameter and 10mm tall.
- Place a second cylinder on the work plane and size it to 10.5mm in diameter and 10.5mm tall.
- Remember: Set the grid snap to 0.5 to size the cylinder to 10.5mm.
- Change the second cylinder to a hole.
- Select both cylinders and align them vertically.
- Group both shapes into a single item to cut the hole through the wheel.
Step 2: Create 3 additional Wheels
- Select the first wheel and change the color to black.
- With the wheel shape selected, duplicate it by selecting Duplicate from the edit menu.
- Move the duplicate away from the original wheel so they are not overlapping.
- Select Duplicate from the edit menu 2 more times to create all the wheels.
Step 3: Create Axles for Your Car
We now have the wheels and body created, but we need a way to connect the wheels to the car. This is exactly what the axles do. We can create them quickly with a couple of cylinders.
- Place a cylinder on the work plane and size it to 10mm in diameter and 45mm tall.
- Select the cylinder and duplicate it by selecting duplicate from the edit menu.
- Position the axles between the wheels and the body so they do not overlap.
- This will put all the parts in position for 3D printing.
Your car should be able to print without support.
- Select Download for 3D printing from the design
- STL as the download format. The .STL file format can be used with a 3D printer.
- Import the .STL file into your 3D printer software and
- Congratulations! You have completed the design and printing portion of the ballon-driven car.