Finished Hovercraft

November 27th, Construction and Almost Completion

Today the team spent the entire day devoted to the construction of the hovercraft.  It took roughly 6 hours to complete the assembly.  We received the parts we needed laser cut from acrylic today and also painted the foam we would be using yesterday in order to be ready to assemble today.  With all of the parts printed or laser cut that we needed and all of the code finished we were ready to assemble.

The first thing done was to create the layout for the LED array we used for the hovercraft.  The LEDs were soldered to long strands of hookup wire previous to today so creating the array would go as smoothly as possible.  After the array was complete holes in the base board of the hovercraft were measured and cut. These holes were created for the lift fans used to inflate the skirt.  The lift fans were installed after the holes were cut and their leads were wired and taped together.  Next, a larger block of foam was carved out to serve as the tower for the push motor and fan to sit in.  The push fan and motor were then installed to the motor mount and then into this tower and attached to the baseboard of the hovercraft. a picture of this tower as installed on the hovercraft is shown below.

  The skirt was then applied and four symmetric holes were cut under the hovercraft base board to serve as the outlet for air forming the crafts cushion of air.  The middle of this skirt was then pinned to the bottom of the base board because through previous testing it was found that a skirt designed in this way achieved the most efficient hover. The skirt design is shown below.

  The first Arduino and Arduino holder then went onto the hovercraft. This Arduino was the controller for the led array. The array was then connected to the Arduino via a breadboard located along the side of the Arduino holder.  The breadboard (and mess of wires due to all of the circuits connected to the board) is shown below. This picture features the competed breadboard with all circuits on it not just the LED circuit.  

Next, the second Arduino was installed on top of the previous Arduino. This Arduino serves to control the LCD display. The LCD display was attached at the same time to the front of the hovercraft and the circuit was tested.The LCD display is shown below.

  Next, the steering blade and base that were laser cut from acrylic were attached to the servo. The servo was then mounted into the 3-d printed servo mount. This assembly was then attached to the hovercraft baseboard directly behind the push motor and fan. This assembly is shown below.

 The servo and push motor were controlled by the third Arduino which was installed onto of the other two.  This circuit was setup and tested. Finally, the Arduino tower topper that was cut from acrylic was attached and the IR sensor tower the was 3-d printed was placed on top of that.  The IR sensor was then hooked up to all of the boards so that they could read it and run the programs correctly. The four LEDs that are also onto of the IR tower were hooked into power. A photo of the IR tower is shown below followed by a photo of the stacked Arduinos.

  After all of this assembly, the hovercraft was ready to be tested.  A picture of the entire hovercraft as well as the video of the first test run is shown below.

A huge amount of work was completed on the project today and it is basically finished. All that is left to do is tweak a few parts of the code and connect a couple more wires and the hovercraft will be completed fully.  

The hovercraft is easier to control that we originally thought and the propulsion from the push motor is exactly what we were expecting. Overall we are extremely pleased with the finished product.

November 26th, 3-D Printed Parts

Today we received the rest of our 3-D printed parts. The servo mount was printed earlier so that picture can be seen in a previous blog. Below are the pictures of how the parts turned out.

Protective Arduino Case

IR Receiver Tower

DC Motor Mount

November 25th, Code

LCD and Servo Code
Below is the code that will run the LCD and the Servo motor. The LCD is a required part of the project and we didn't have a specific need so we wanted to make it cool. When the hovercraft the LCD will read "System Charging". While driving the LCD will then read what direction it is driving. For example "slight left, slight right, left, and right". The servo code will turn the servo in increments of 30 degrees. LED Code
Another required element to the project was the use of LED's. Again, we wanted to use this feature to make our hovercraft cooler. We decided to use red and blue LED lights. The code below is used to control the LED lights. When the Hovercraft turns a certain way, lights on that side will blink. Motor Control Code
This code is used to control the big fan on the back of the hovercraft.

November 24th, Testing of Design Choices

IR Receiver Tower

One of the more important aspects of our design is that a single IR receiver needs to relay the signal it receives to multiple Arduino boards.  Recently we tested such a set up.  After a fairly large amount of tinkering we were able to get the receiver to output to three different Arduinos with limited interference.  This simplifies our task of wirelessly controlling the hovercraft. Since the IR receiver plays such a crucial role in our design we decided to build a tower to mount the IR receiver on. The design for the IR tower can be seen below.

This weekend other aspects of the hovercraft have been nailed down.  For example the LED array designs have been completed as well as the structure of the LCD screen code. 

There are still a few decisions that have to be made.  Perhaps the most tedious of these is deciding what will be run off of each board in order to ensure we do not exceed the maximum current the Arduino can output.

There is still a lot of work to be done before December 4th despite the fact that the majority of the design work has been done.  A significant amount of soldering and circuitry are primarily what remains.

November 21st, Working in Lab

3-D Printing

Today in lab we were able to go down to the Plastics lab and use their 3-D printer. We decided to print our servo motor mount that we created so the servo could be attached to the hovercraft base. The mount took about 45 minutes to print and used about 0.55 cubic inches of material. The servo motor mount can be seen below.

Protective Case for Arduino

After 3-D printing one item we decided to finalize the other components that we wanted to print. One of the most important components for our design is the protective case for the Arduino. This case is important because we will be using multiple Arduinos and we want to be able to stack them on top of each other so they don't take up a lot of surface area on top of the base of the hovercraft. In lab we made a few modifications to the previous design for this case. Specifically we added more holes to the sides of the case. This will help because it will allow wires to be connected to the Arduinos from 3 sides of the case and will decrease the amount of material used. We have sent the part to be printed and we need 3 of these parts shown below.

Fin For Steering Hovercraft

In lab we also worked on the design of a fin. This fin would be placed at the back of the hovercraft and would be used to steer it. We plan on cutting the fin out of acrylic.

Layout of Hovercraft Base

At this point in the design process we have made most of our decisions on what components will be incorporated into our final design. We wanted to see how these components would fit on the base of the hovercraft so we have made a model of where the components will be assembled on the the hovercraft.
In the picture below there are abbreviations for each part:
BP = battery pack
LF = lift fan
FB = fan base
SM = servo mount
BB = bread board

November 15th, RC-Car parts

In the last post we were successfully able to the hovercraft and have it slide smoothly along the floor. This was a very big step for our group but there was obviously a lot of work left to do to make our hovercraft better. After watching the video of the hovercraft sliding there were a few obvious problems with our design. The biggest being that the hovercraft needed to be pushed manually in the direction that we wanted it to slide. We want to be able to control the hovercraft so that some type of remote control can tell the hovercraft to turn on and drive in a certain direction. To address this problem we attached a high speed DC motor (14,000 RPM) to the back of the hovercraft. The placement of this motor can be seen in the picture below. When turned on this motor pushes the hovercraft in a certain direction based on how the fan is angled.

We are very pleased with the outcome of the fan we added to push the hovercraft forward. The next matter to attend to is being able to control which direction the fan is pointing so we can control which direction the hovercraft goes. In an attempt to figure out how to control a small vehicle we purchased an RC car from Walmart and took it apart to inspect it's parts and see how we can use those parts in our design. Below is the picture of the RC car and the parts we believe that will be useful to our design.

This RC car gives us an RC remote control with an antenna, 2 small DC motors, a battery pack, some small plastic gears, and the RC board with a receiver antenna.

  Another problem with the previous design is that even when we push the hovercraft in one direction, it doesn't stay going in the correct direction for very long. To address this problem we need to more uniformly distribute the weight on the base of the hovercraft and make sure that the skirt is uniform so that air is distributed correctly. This problem will need to be addressed as we decide exactly what components we want to be on the base of the hovercraft.

November 14th, New Fans

While working on the project earlier in the day we came to the conclusion that the fan we had planned on using (2000 RPM) wasn't spinning fast enough to lift the hovercraft. Luckily we just acquired two new fans. The new fans (15,000 RPM) spin at a greater speed and are a lot smaller than the first ones we were trying. The smaller fans could allow us to use more fans in our design. We decided to try using two of the smaller fans and a Styrofoam base.  We tried to distribute the weight as evenly as possible with the battery pack in the middle. The setup is shown below.

After setting up the fans and battery pack on the Styrofoam base, we made a skirt out of a different material than we had previously used. In previous attempts we had used a supermarket bag but in this attempt we decided to use a clear painter's plastic. Below is the video of the first time we turned the new fans on with the new set up.

We were very happy that the fans we were using were finally able to lift up the hovercraft. The hovercraft was not able to slide very well because the skirt didn't have a hole in the bottom. In the next video below there is a hole in the bottom of the skirt and you can see that the hovercraft is able to slide smoothly along the floor.

Next we will try to make a bigger and more stable version of this hovercraft. We still are debating adding more fans to the design and are still in the trial and error stage.

November 14th, Lift Tests

Before assembling our hovercraft we wanted to make sure the fans we purchased were able to lift a miniature version of a hovercraft. We first tried by attaching the fan to a plate and making a skirt out of a plastic bag. When researching different homemade hovercrafts we realized that a common theme is a hole in the bottom of the skirt. We weren't sure how big the hole was supposed to be so we decided to go with a guess and check procedure. In our first attempt, we cut the hole in the skirt about as big as the fan we were using. This attempt is shown below on the left. The fan was not able to fill up the skirt and lift it off the ground. We decided to make the hole in the skirt smaller so that more air would fill the skirt. This attempt is shown on the right but also failed in lifting the plate.

 We decided to change the base of the hovercraft from the plastic plate to a piece of the Styrofoam that we will be using in the full scale prototype. Once again we tried two different types of skirts. First we tried a skirt without a hole as shown below on the left but this method did not work. Next we tried cutting a hole in the skirt, as shown below on the right, but again the hovercraft did not lift.

After many tests we thought that the problem wasn't in the design of the skirt, but in the power of the fan. We thought that the fan wasn't spinning fast enough to lift the hovercraft. We decided to try increasing the voltage to the fan and the results were minimally better but still not enough to sufficiently lift the fan. After a few hours of trying different conditions we concluded that these fans (2000 RPM's) were not going to be able to be used for our hovercraft.

November 14th, Working in Lab

Fans:

Today was the first day during lab that we got to work with the fans that we purchased. We were able to power the fan with a 12 volt battery pack using the code below.

LCD IR Remote:

We also worked on using an IR remote to control the message that appears on the LCD. A video is shown below of the remote changing the message. The code used is also posted below.

November 7th, Solidworks Parts

Protective Case:

Each group is allowed to print 1 cubic inch of material for each member. Since we have four members we are allowed to use up to 4 cubic inches of material for this project. We decided that the best use of our material is to make protective cases for different parts of our hovercraft. One component of the hovercraft that we feel it is important to protect is the arduino board.

This case for the arduino will help us in two major ways. First and foremost it will  provide support and protection to the arduino making sure that it will not get crushed or wrecked upon impact or the hovercraft crashing. Secondly, having the arduino housed in a case will make it easier to attach to the hovercraft without worrying about damaging it. We were able to design a case for the arduino that utilizes only 0.7288 cubic inches. We are happy with this because we think that we may need to use up to three arduinos. Therefore we would need three arduino cases totaling about 2.2 cubic inches of material.

Servo Motor Mount:

Realizing we will have extra material left over we decided that we would also like to create protective cases and mounts for other important components in our design. Next we decided to make a mount for the servo motor. This case used only 0.36 cubic inches of material.

After creating 3 arduino cases and 1 servo motor mount we would only have used about 2.56 cubic inches of material. This leaves us with about 1.5 cubic inches of material left to be used for the rest of the project.

Where Parts Will be Mounted:

This is a very rough estimate of where we think we will mount parts on top of the hovercraft. We aren't sure how many fans we are going to use or how many arduinos we are going to use. This picture is just an idea but is still subject to change. In the picture the parts labeled F represent the fans and the protective cases for the arduino look the same as they do above.

 

November 6th, Component Acquisition

Fans To Support Hovercraft Skirt

We have found the fans that we are going to use for the bottom of the hovercraft.  We are going to order four because they are only $8 each.  If we only need two or three fans on the bottom then we will use the remaining fans to steer the hovercraft.  It just so happens that these fans are Riverhawk Colors.  Here are pictures of all the fans:

We are definitely buying all four of these fans.  

November 6th, Turning Motor On and Off With an IR Receiver

What We Wanted to Accomplish:

I order to create the hovercraft we must have a way to turn on the fan that will blow air into the supporting skirt of the hovercraft.  We wanted to see if we could turn on the motor using an IR Receiver and a remote.  After many changes to the code we final accomplished the task.  

Here is a Picture of the Setup Board: 

Here is a Video of the Motor and IR Receiver in Action: 

Here is a sample of the code: