Project Overview

The goal of this project was to design, build, test, and successfully demonstrate  a remote‐controlled amphibious all‐terrain vehicle (ATV) system that traverses a ~1250’ diverse water and land course through the Sarah P. Duke Gardens and retrieve an elevated target object. We were awarded points based on three components of the course:

  1. Traverse and navigate 600’ of water in the Fish Pond
  2. Exit the pond and travel a further 650’ across mixed rolling grass, gravel,  and flat stone path terrain
  3. Retrieve a target object placed 8‐feet above the ground on a vertical  pole

Course Map

As program manager, I was responsible for overseeing the entire project and making sure that each subteam was keeping up with their responsibilities. I also served as the contact point between the team and the staff at Sarah P. Duke Gardens to ensure that we were not impeding on their space at any time throughout the project. I was also responsible to tracking our budget of $600.

A video summary of the project can be found here.

Design Process

Brainstorming

When first presented with the project, I had no idea how my team would even begin to approach it; never before had I been presented with such a long and diverse task. We decided to break brainstorming down into 3 categories: land, water and air. After multiple team brainstorming sessions and a lot of deliberation, we decided to build a device that would have a 3D printed frame with four wheels for land travel and two motors with propellors for water travel. The frame would be waterproof and all of our electronics would be housed inside of it. For the air portion of the course, we decided to attach a drone to the top of our rover that would ascend to the top of the pole and knock off the ball.

Sketches from our final brainstorming session

 

Prototyping

Once it was time to start prototyping we split into three subteams- land, water, and RC/air. As a member of the water subteam, we were responsible for working closely with the land team to insure that the frame fit the needs of both wheels and propellors. We were responsible for choosing motors and designing propellors to get the device across the pond. We also had to make sure that the frame was waterproof in order to keep our electrical components secure and that the entire vehicle was buoyant enough to stay afloat.

As we only needed the vehicle to move forward in a straight line, we decided to place two motors with propellors that we designed on SolidWorks and 3D printed on the back of the frame. In order to waterproof the frame, we lined the inside with foam which also positively contributed to its buoyancy. In addition, we sealed all components of the frame with a waterproof sealant. After some initial testing in which the vehicle was not able to stay afloat, we added foam blocks underneath the frame.

Testing buoyancy

Once we had figured out how to keep the vehicle afloat and had waterproofed it fully, it was time for the land team to add the wheels and the RC team to ensure that all of our electronics were in check.

Final Test

On test day our team was met with many complications. Upon leaving the lab the night before testing, our vehicle seemed to be working perfectly. However, when we arrived the on testing day an hour before run time, this was not the case. We put the vehicle in the sink to triple check that there was no water getting in but when we removed it from the sink we found the bottom of the frame to be lined with water.

Trying to identify the source of incoming water on test day

We considered many different options but after nearly an hour of deliberation, the decision was turned over to me as PM and I decided that the safest bet was to remove the propellors and seal off their connection to the frame. While a risky decision, we were confident that, although slowly, the vehicle could make it across the pond with only the power of the wheels and we did not want to risk ruining all of our electrical components and not being able to complete the course at all. With a very differently functioning vehicle than we had intended on, we headed down to the Duke Gardens to test it.

Against all odds, we ended up successfully completing the course in just under our allotted time of 1.5 hours.

Reflection

While the events of testing day were far from ideal, it challenged the team to think quickly and consider many different scenarios in order to make an important decision. The many different components of this project taught me a lot about designing for different terrains. My leadership role of program manager taught me how to keep a team on track and due to our unforeseen complications, allowed me to take control of a situation by making a decision on behalf of an entire group that I seemed fit. I also gained experience speaking with staff from throughout Duke on behalf of my team and our project. Working on this project was an invaluable experience that taught me so much about what it means to be both a good engineer and a good leader.