No matter what kind of project you want to put in space, you’ll need some way to tell it what to do, and some way to get some information back. To do that, you’ll need to connect to the power and data systems on board the Binar satellite.
So, whether you’re building an instrument to help measure climate change, or you just want some cool photos of your Hot Wheels car in space, you’ll need some kind of electronics to go along with it.
If electronics and coding aren’t your jam, don’t worry! You’ll also need structural engineers (to help make sure your payload physically connects to the spacecraft), scientists (to design your experiments and interpret your data), and team members to help with project management, documentation, and outreach.
If electronics and coding are your jam, this kit will help you to practice some of the fundamental skills required to build a payload for a Binar cubesat.
This introductory activity will give you a chance to practice:
- Prototyping a project using a breadboard
- Selecting a component and reading a data sheet
- Programming a microcontroller
- Reading and interpreting input from a sensor using a microcontroller
- Responding to a command from outside your circuit
Each step of this project builds on the last, so keep your projects assembled between steps if you can.
Parts
Each kit contains enough equipment to run three simultaneous activities. We picked these parts based on price and availability to make the program as accessible as possible. The same activities can also be adapted to work with other parts (in particular other microcontrollers, such as Arduino or Micro:Bit hardware).
If you’d like to source a kit for yourself, you can grab the components listed in the bill of materials, or order the entire project from Mouser Electronics. If you have any questions about sourcing parts, drop an email to binarx@curtin.edu.au.
Your cubesat bus
The bus is the part of the spacecraft that everything else sits in, including the payload, which is the part of the spacecraft that actually does the mission. Binar uses a 10x10x10cm 1U bus, with a core that contains everything the spacecraft needs to run (like power and a computer) as well as a structure for the core and the payload to sit in.
For our mission, we’re using a cardboard cubesat as the bus, and the breadboard from our kit as the core. Before you start, you’ll need to cut out and assemble your spacecraft bus using the printable template and fold it according to the instructions below.
For this project, we’ll be attaching a piece of prototyping gear called a breadboard, and some wires called jumper wires, to our bus. These let us plug and unplug components without having to solder them in permanently. If you’ve never used a breadboard before, you may want to read this tutorial before you get started.
These components form the basis of your project, and will be used to connect all your other components together. They’ll also be handy prototyping supplies to have around when you start work on your full payload.
| Quantity | Item | Part number |
|---|---|---|
| 3 | 170-point breadboard | P1020A |
| 30 | Assorted Pin-pin, Pin-socket, socket-socket jumper leads | P1016, P1017 |
| 3 | 9V Battery Snaps | P0455 |
| 3 | 9V batteries | any |
You’ll find these components in the bottom section of your box, if you got one from us.
Equipment
You will also need some extra equipment outside of what’s provided in the box:
- Multimeter
- Windows computer, with at least one USB port and the ability to install the Arduino IDE and Tiny AVR Programmer drivers.
1. Powering up
The first thing we need to do is turn our battery voltage into something a little bit smaller and more consistent. On the spacecraft, your payload will be supplied with anywhere from 6.0-8.4 volts, depending on how much charge the batteries have. In this kit, we’re using a 9v battery, which will also decrease slowly as the battery discharges.
In this part of our project, we’ll use a regulator to drop that down to the 5v our components use, and some capacitors to make sure there are no sudden changes.
Parts
You’ll find these in the top row, first left compartment of your box.
| Quantity | Item | Part number |
|---|---|---|
| 6 | Linear Voltage Regulator | 78L05 |
| 6 | 0.33uF Capacitor (at least 10v) | [example] |
| 6 | 0.1uF Capacitor (at least 10v) | [example] |
Equipment
- Multimeter
Instructions
2. Sending a message
Now that we have the power supply we need, we’re going to get our microcontroller up and running, and test it by blinking an LED.
Microcontrollers let us use code to interact with our circuit. They let us measure what’s going on in the parts of the circuit they’re connected to, and control parts of that circuit based on what we measure.
We’ll be putting code on our microcontroller from a computer using a device called a programmer. Before you start this part of your project, you’ll need to set your programmer up by following the instructions found here. You might also find the ATTiny Quick Reference Sheet useful to print and have on hand.
Parts
You’ll find these in the top row, second left compartment of your box.
| Quantity | Item | Part number |
|---|---|---|
| 3 | ATTiny85 Microcontroller | Z5105 |
| 1 | Tiny AVR programmer | PGM-11801 |
| 6 | Red LED | [assorted] |
Equipment
- Windows PC with at least one USB port
Instructions
Need help? Check the Interactive Schematic & Arduino Code.
3. Receiving commands
Our cubesat can blink out a message to us – so how do we send one back?
For this activity, we’re using a button, but the same principles apply whether we’re a cubesat getting commands from the ground or a payload getting commands from our spacecraft bus.
You can find out more about how interrupts work here, and more about the various interrupts available on the ATTiny85 by looking at the datasheet.
Parts
You’ll find these in the third top row compartment of your box.
| Quantity | Item | Part number |
|---|---|---|
| 6 | Tactile switch | EVQ-PVG05K |
Equipment
- Windows PC with at least one USB port
Instructions
Need help? Check the Interactive Schematic & Arduino Code.
4. Making measurements
We’re going to add a temperature sensor (and an extra LED) to our circuit. By measuring how many volts are coming from the output pin of this sensor, we can determine whether the sensor is above or below a particular temperature, and light up the right LED.
This one will require some experimentation to calibrate. Having a selection of hot and cold items on hand to test might be useful.
You can find the equations we refer to in the video in the datasheet for our temperature sensor.
Parts
You’ll find these in the fourth top row compartment of your box.
| Quantity | Item | Part number |
|---|---|---|
| 6 | Board Mount Temperature Sensor | EVQ-PVG05K |
| 6 | Blue LED | [assorted] |
Equipment
- Windows PC with at least one USB port
- Multimeter
Instructions
Need help? Check the Interactive Schematic & Arduino Code.
5. Looking with light
We’re going to modify our circuit to detect light, instead of temperature. We’re still measuring how many volts our sensor gives our microcontroller, but we’re using slightly simpler components, so we’ll have to do an extra couple of steps ourselves to get it working.
Parts
You’ll find these in the fourth top row compartment of your box.
| Quantity | Item | Part number |
|---|---|---|
| 6 | 5k-10k Light Dependent Resistor | Z1621 |
| 6 | 10k Resistor | R0249 or [assorted] |
| 6 | Green LED | [assorted] |
Equipment
- Windows PC with at least one USB port
- Multimeter
Instructions
Need help? Check the Interactive Schematic & Arduino Code.
