UKZN Phoenix-1B MK II-R & MK I Rocket Launches – Part 2

3D Printed parts used in the Phoenix Rockets

In the earlier post, we looked at the history of the Phoenix Hybrid Sounding Rocket Program (HSRP), the 2 rockets that were launched, and the record-breaking flight. In this post, we will take a more in-depth look at how 3D Printing assisted the launch as well as DIYElectronic’s contribution through Chief Engineer and CTO, Robert Mawbey.

If you missed the first post then follow this link. We recommend reading it so you have a better understanding of what is discussed in this post.

3D Printing and Aerospace

3D Printing is disrupting just about every industry across the world and aerospace is no different. Due to the nature of rockets and spacecraft, the ability to respond to sudden and unexpected situations is vital. The use of 3D Printing in the aerospace industry initially made headlines in 2014. A specialised 3D Printer aboard the International Space Station (ISS) printed a ratchet wrench as part of a NASA technology demonstration. Since then 3D Printing has continued to play a part in various aerospace agencies across the world.

It has even played a part in the Phoenix Hybrid Sounding Rocket Program (HSRP), a program started in 2010 by UKZN. The program was developed by UKZN’s Aerospace Systems Research Group (ASReG). During development and prior to launch of the Phoenix-1B some parts of the electronic enclosures and internals were 3D Printed as it offered the team the possibility to react to and fix issues much faster. To learn more about the role of 3D Printing in the Phoenix program watch our Part 2 video.

DIYElectronics and Robert Mawbey

DIYElectronics and Robert Mawbey contributed to the Phoenix Rocket Program.

Before we get into the details of our contribution to the program let’s take a quick look at DIYElectronics and Robert Mawbey.

DIYElectronics is an online electronics and 3D Printing store born in 2013 from 3 generations of knowledge in the electronics industry. We pride ourselves on providing high-quality products at an affordable price and with unrivaled support. We are an avid supporter of the open-source movement and continuously evolve to meet the ever-changing needs of clients.

Robert Mawbey is the Chief Engineer and CTO at DIYElectronics. He has been part of the Phoenix Hybrid Sounding Rocket Program since 2013 during his undergrad at UKZN. His role in the program is Avionics and Telemetry electronics engineer.

Robert designed custom embedded electronics to control the Main Oxidiser Control Valve (MOV) between the tank and motor, as well as the vent valve and override/safety systems. In addition, he built a wireless video telemetry system for live video from the nose cone of the rockets. Most of the mounts, cases, and antenna frames that Robert used were 3D Printed. A BIQU B1 was taken along to the test range in case last-minute adjustments were needed.


Avionics are the electronic systems used on aircraft, satellites, and spacecraft. This can include systems such as communications, navigation, and the management of systems. This includes the vast number of systems found in aircraft and spacecraft.

There were 2 servo motors were used to control 2 valves on the rockets. The first servo was connected to the launch trailer and controlled the vent valve. The second servo was located in the interstage section of the rocket and controlled the main oxidiser control valve.

The valves and override/safety system were monitored and controlled by a custom-engineered receiver module. The receiver module is connected to a computer by USB allowing the systems to be monitored live by a custom python application.

Vent Valve

During fueling of the Phoenix-1B the oxidiser is slowly pumped in from the bottom and this causes pressure to build up at the top of the tank. The purpose of the vent valve is to release the pressure as needed to ensure consistent fueling.

Main Oxidiser Control Valve

The Main Oxidiser Control Valve controls the opening of the valve during launch. When T=0 a signal is sent to the servo and it opens the valve to release the oxidiser.

Override/Safety System

If a problem occurs during preflight or at launch the rocket needs to be made safe even if the umbilical cable has become disconnected. The receiver module remotely activates the valves to empty the tank, all from a safe location.

The interstage section showing the Main Oxidiser Control Valve (MOV)


Telemetry is the in situ collection of data and other measurements from set points or automatic transmission. A telemeter is a physical device used for reading or monitoring the telemetry data.

Robert Mawbey was tasked with designing a camera system that would allow ASReG to view video from the rocket itself. The Phoenix-1B MK II-R was equipped with 1 simple analogue camera while the MK I was equipped with 2 high-quality cameras. The cameras were activated only during launch and flight as they had a limited power supply to reduce weight and footprint in the rocket.

The use of cameras on a rocket provided an interesting challenge as not only was a way to power the cameras needed but a way to receive the video feed. The speed and distance of the Phoenix rocket make it more difficult to receive the data. Robert created and 3D Printed a variety of omnidirectional and directional antennas to receive the video and other telemetry. The antenna used can be compared to candles and torches to get a better understanding. An omnidirectional antenna is like a candle, it lights up a wide area but has a fairly limited range. A directional antenna is like a torch where the beam of light is more focused and able to reach further but has to be aimed/adjusted to get the best result.

The cameras were installed into 3D Printed mounts and enclosures located in the nose cone of the Phoenix rockets. These cameras were connected to a small battery, video transmitters, and a cloverleaf omnidirectional antenna to send and receive signals. On the ground were a variety of antennas including 2 of Roberts. The first antenna was a circularly polarized helical directional antenna and the other a linear polarized directional antenna. These antennas were mounted on tripods and aimed at the predicted rocket trajectory to allow for optimum data transfer.

Antennas used to receive signal from the Phoenix Rockets.
(Left) Linear polarized directional antenna. (Right) Circularly polarized helical directional antenna.


We jumped at the chance to do a quick interview with Robert Mawbey about his experience.

How long have you been part of the ASReG Phoenix Program (HSRP)?
“I have been part of the ASReG Phoenix team since 2013 during my undergrad at UKZN.”

What is your role in the program?
“I’m Avionics and Telemetry electronics engineer.”

What did you contribute to these launches?
“I was tasked with designing custom embedded electronics to control the main oxidiser control valve (MOV) between the tank and motor, as well as the vent valve and override/safety system. In addition I built a wireless video telemetry system for live video from the nose of the rocket.”

Has 3D Printing always been a part of the program?
“In 2014 I began to introduce 3D Printing into the program. I co-authored a paper about the experience.”

How was 3D Printing used during these launches?
“Lots of parts were 3D Printed for mockups such as launch lugs and bulkheads to check the design before getting them machined.”

What were the goals of each rocket?
“The first rocket, MK II-R, was designed for distance. It had no recovery system, it had nothing. The MK I was designed to take a payload of 10kg to an altitude of 10km and we got to 11km.”

How does it feel knowing a rocket you worked on has set a new record?
“It’s a fantastic feeling and a great relief to finally have achieved the goal we set out for more than 9 years ago! It has also been personally rewarding to be invited back to the team to be able to share my skills again, as an industry expert.”


Congratulations to everyone involved. We at DIYElectronics wish you all the best for the for future launches. It has been exciting to have have our Chief Engineer and CTO Robert Mawbey on the team and we wish him all the best for future work with the program. If you enjoyed this article consider sharing it on social media. Watch the Part 2 video on our Youtube. To keep up to date on future Phoenix sounding rocket launches and everything DIYElectronics related such as new products, projects, and Maker news, check out our social media. FacebookInstagramTikTok, and Twitter and website.

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