UMSATS CubeSats Division

UMSATS

The University of Manitoba Space Applications and Technology Society (UMSATS) is an organization whose vision is to foster a culture of space exploration by making aerospace engineering and science more accessible. Our Mission - to develop Sounding Rockets which we use to compete at various international competitions, and Nanosatellites as part of the Canadian Satellite Design Challenge (CSDC) in which we placed first in 2018.

For 2021 we are beginning a new design cycle for the CSDC with the intention to design a fully functional 3-U CubeSat and grow the engineering design skills of our members.

The Satellite

UMSATS’ Satellite team has two missions. Its primary mission is to carry an earth-observation camera, which will be capable of capturing ground imagery on an on-demand basis, with these images relayed via amateur radio operators (AROs). Its secondary mission is to bring to orbit samples of cyanobacteria, which are being considered for life-support and other purposes.

The satellite (known as TSAT-5) uses a modular “3-U CubeSat” design consisting of 5 distinct modules: Payload, Communications, Command and Data Handling, Power, and Attitude Determination and Control. Each of these communicates through the CAN bus protocol. Communications between the satellite and UMSATS’ ground station located at the University of Manitoba will take place over the amateur radio bands.

Figure 1. Subsystem Overview

UMSATS’ Communication subsystem plays an important role in public outreach. The satellite will, when not in view of the main ground station, be connected to various Amateur Radio Operators and their stations. Here, AROs are able to request an image from the satellite’s onboard camera, which will be downlinked through Amateur Radio bands. We hope that this functionality can be used to engage with students worldwide and increase awareness of Amateur Radio and Space Exploration.

PCBs

Comms

As the satellite has full-duplex capabilities, the Comms board will have two sections. The Very High Frequency (VHF) side will have a microcontroller for signal processing purposes and communicate to the rest of the satellite through the CAN bus. The Ultra High Frequency (UHF) side will be connected directly to CDH. Both sides of the board will have filtering and matching circuitry, and routes to a secondary PCB where the antenna is connected.

Figure 2. Communications Module (SolidWorks Model)

CDH

The purpose of the CDH (Command and Data Handling) System is to coordinate the tasks, data, and state. The CDH consists of a PCB controlled by a Smartfusion2 System-on-Chip. It has a direct SPI connection to the UHF radio board and the camera for taking pictures and sending them to the ground station. It also features an analog to digital converter for temperature detection and other features, a CAN transceiver for communication with other subsystems, 68 Mbits MRAM, and 4 Gbit NAND Flash.

Figure 3. Control and Data Handling Module

Payload

The payload subsystem has two main objectives during the mission. The first of which is to onboard a camera capable of taking pictures of the Earth when requested by an Amateur Radio Operator (ARO).

The second objective of the Payload subsystem is to document the effects of microgravity and radiation on the growth of Anabaena cylindrical (cyanobacteria) for low-orbital gravity research towards food and oxygen sustainability for long-term space travel.

Both objectives are achieved through the help of an onboard computer, sensors, and peripherals all residing on the Payload PC board.

Figure 4. Payload Module

Power

The Power System consists of two boards, the power control unit (PCU) and the battery module (BM). The purpose of this system is to deliver regulated power to all the subsystems of the satellite, monitor and report various data, perform load shedding based on the state of charge and charge the onboard batteries through the help of onboard maximum power point trackers (MPPTs). The PCU monitors the health of the regulated power rails, the state of charge of the onboard batteries, the power consumption of each of the subsystems, the charge, and the discharge rate.