The field of high altitude ballooning is an effective and relatively inexpensive way to deliver scientific payloads to the upper atmosphere for data collection. High altitude balloons can be grouped into two main categories: zero pressure and burst. The burst balloon is designed to ascend constantly until it reaches a certain altitude, at which point it will burst allowing the payload to descend back to the ground. The zero pressure balloon is much larger, and is designed to ascend to a certain altitude, then float until the flight is terminated. The zero pressure balloon is more versatile than the burst balloon as it can float at neutral buoyancy for extended data collection. The burst balloon is significantly less expensive so it is commonly used by facilities that use meteorological sounding packages and university ballooning groups with smaller budgets. The Goal of the altitude control system is to provide the ability to fly the lower cost burst balloon at neutral buoyancy. This will allow users to collect data on a floating platform without the increased expense of a zero pressure balloon. This report will detail the needs description, list the stakeholders of this project, and review the project goals and constraints.
The following functional specification overviews the high level requirements of the valve control system. Very few if any technical details will be provided however the overall function of the system will be detailed. The functional specification starts with a black box model which describes what each individual subsystem does along with a high-level look at how the systems are connected together. The next section is functional specifications. The functional specifications provides a granular look at what each subsystem must do to accomplish the overall goal of the project. Each high level function is broken down into smaller sub functions as needed. Finally the design metrics for the project will be presented. The design metrics are the overall design goals that the end product will be weighed against to determine if the project was successful or not.
This section of the report will cover the design alternatives proposed by the capstone group. These design alternatives are a group of ideas that could possibly be used to accomplish the functional requirements. This report will discuss the design alternatives in detail, then rank them based on operational criteria proposed by the Capstone group. This report will also discuss the user operation requirements for the project. These can include ergonomics, setup, maintenance, and correct operation of the product.
This report will detail the Project planning for the Weather Balloon Altitude Control system currently being designed. This report will contain risk analysis information that covers the severity and probability of the failure modes possible for this system. Next, plans for mitigating risk items above the design threshold will be detailed. A brief breakdown of the work structure for the project will also be included. This will cover high level tasks that need to be completed for the project. The responsibility matrix will assign various design goals to certain members of the design team. Finally, the report will be concluded with a project schedule that will include a timeline for project goal completion.
The design alternative that was chosen from the decision matrix is a micro-controller with an integrated radio and a rotating gate valve. Now that these design choices have been selected above the others they will be further explained and developed. The individual components will be explained in greater detail along with how they integrate with the other components in the overall system. In order to make the best overall product a number of interviews were performed to get some feedback on how the current design could be improved and if there should be any additional features added. In accordance with the feedback that is received the design will be potentially changed or added to. Even though the seemingly best design has been chosen there is some potential for some design choices to fail. In order to prepare for this possibility a contingency plan is developed and presented here.
This report will detail the system Architecture for the Weather Balloon Altitude Control Project. The report will first explain in detail the system architecture plan for the project, covering the major interfaces, their position in the assembly, and their function. This includes the flow tube, the gate valve, and the nozzle of the balloon, the main payload microcontroller, and the valve servo. This section will be divided into mechanical and electrical groups to clarify the nature of each system and its respective interfaces. The next section will cover the system interfaces together in a block diagram. This representation will provide better insight into the different sections, and how they interface. The next section will detail the sub-system interfaces. This includes the valve controller, any third party communication payload, and the commands uploaded by the user during flight. For this project, these are entirely electrical, and are explained below in more detail. Finally, the report will cover the user interface for this project. This will include any setup, handling or operational interfaces the user may encounter while using this system. For this project, user interface includes attaching the balloon to the valve, filling the balloon through the valve using the fill station, attaching the payload to the bottom of the valve, programming the microcontroller, and interfacing the user's existing communications payload to the valve controller.
This section outlines the materials required for this design and their specifications. This product can be divided into two sections, the mechanical or valve section and the electrical or controller section. The valve section will require numerous custom and off the shelf pieces of hardware to produce. The electrical section requires microcontrollers, a GPS unit, various circuit elements, and two custom made printed circuit boards. There are some possible production issues that need to be kept in mind when designing and getting ready to produce this product, such as a shortage of the items required to build this product. A potential customer will want to know how the product will perform and what its expected lifetime is, for instance the fact that this product is designed to for one use, but could potentially last much longer should the consumer choose to retrieve and reuse it.
The field of high altitude ballooning is an effective and relatively inexpensive way to deliver scientific payloads to the upper atmosphere for data collection. High altitude balloons can be grouped into two main categories: zero pressure and burst. The burst balloon is designed to ascend constantly until it reaches a certain altitude, at which point it will burst allowing the payload to descend back to the ground. The zero pressure balloon is much larger, and is designed to ascend to a certain altitude, then float until the flight is terminated. The zero pressure balloon is more versatile than the burst balloon as it can float at neutral buoyancy for extended data collection. The burst balloon is significantly less expensive so it is commonly used by facilities that use meteorological sounding packages and university ballooning groups with smaller budgets. The Goal of the altitude control system is to provide the ability to fly the lower cost burst balloon at neutral buoyancy. This will allow users to collect data on a floating platform without the increased expense of a zero pressure balloon.