This week, I have started looking into what research methods I will use to evaluate the project and the communications bus (which I’m calling AHABus at the moment – Abertay High Altitude Bus).

Practical Work

The first part of the project will be practical – I want to design and build a hardware and software bus for High-Altitude Balloon missions. The goal is to create something that can:

  • Provide a documented hardware data interface to payloads (Payload Data Bus).

  • Provide a documented software protocol that payloads must comply with.

  • Design the flight software controlling the main computer and the data bus.

  • Design the radio communication protocol used by the flight computer to forward data from payloads to a ground station.

  • Choose and implement a FEC (Forward Error Correction) algorithm to minimise data loss over the radio link.

  • Build a prototype that can be tested on the ground, and given enough time and funding on a test mission.

Analysis

Once I have a prototype of the AHABus, I’ll have to do a critical analysis of it to answer the research question:

What are the advantages, issues and obstacles in designing a generalised intra-payload and long-range communications platform for High-Altitude Balloon scientific missions?

I have broken down the question in two more focused questions I will have to answer:

  • What is the data bus’s performance? (reliability, throughput, power, timing)

  • What is the radio-link protocol’s performance? (reliability, throughput)

Based on what I want to know, I can device a method to answer these questions:

  • [quantitative] Evaluate the radio-link system through range tests.

  • [quantitative] Measure data transmission, loss rates for the radio link with and without chosen FEC algorithms.

  • [quantitative] Measure the data transmission and loss rate on the data bus.

  • [quantitative] Measure the timing performance of the data bus: time between when a payload’s data is available and when it’s been added to the radio transmission queue.

  • [quantitative] Measure the power consumption of the data bus & computer.

  • [qualitative] Evaluate the performance of the overall system through hardware-in-the-loop, “day in the life”-style tests: a test of all systems, integrated, in a simulated mission timeline.

I’ve finished the slides of my pre-proposal presentation, which sum up all of this, plus the aim, objectives, question and literature I have researched for the project so far: proposal slides