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.