Engineering a rover for another planet adds another layer of complexity as compared to working on Earth-based constructions. To make sure the parts survive not only the trip to its eventual destination but also the harsh conditions on the Martian surface, space-grade components are essential. Once on Mars, the wind-driven Tumbleweed rovers will be exposed to unique environments and conditions our engineers must take into account in the design process.

To allow for faster iterations in early phases of prototyping and avoid the high cost of space-grade materials, 3D printing was Tumbleweed engineers’ preferred method for the elaborate mechanical systems. Through our new CNC machine, provided to us by German company CNC-Step, our prototyping approach went through a drastic change, as described in our previous blog posts.

A lack of precision and insufficient strength are two major drawbacks when working with 3D-printed materials. With the CNC machine, parts can be milled from metals, for example out of a strong aluminium alloy, allowing it to withstand very high pressure differences. Tumbleweed engineer Guillaume explains: “If you have more skill and more and more time to spend on it as well, you can make these very intricate, elaborate parts with many cuts and with very high precision that look a lot closer to something that would be considered flight hardware.”

As our engineers develop the Tumbleweed Mars rover, different aspects of the structure – the outer arcs, the connecting sails, the electronics – move into focus. Over the past two years, the rover’s unfolding mechanism has been central to the work of our engineers in Delft. When descending toward the Martian surface, the Tumbleweed rover must unfold into its characteristic spherical shape at precisely the right time to ensure a smooth landing. The engineering of this complex and novel process has gone through many changes as our engineers learn more about what works – and what does not – through new designs and repeated testing.

Traditional Mars rovers have brought us many important insights into the Red Planet’s surface in their years of travelling across it. One major drawback of these large, wheeled rovers, however, is their speed: Curiosity, for example, has travelled less than 35 kilometres since arriving on the planet in 2012. This is one of the points our wind-driven Tumbleweed Mars rovers aim to address: Travelling at up to 18 km/h, swarms of our rovers will be able to cover large areas in a short time.

While the increased speed means that the swarm can collect data across the planet quickly, it also makes it more difficult to accurately determine the location at which a data point is collected. In contrast to Earth, Mars does not have dozens of satellites in orbit that help create a precise geolocation system. Additionally, the rovers will be rolling almost all the time. From this unique challenge, our engineers have developed a novel Location and Attitude Determination (LAD) system, suited to the Tumbleweeds’ requirements.

Designing and prototyping the Tumbleweed Mars rover poses a set of unique engineering challenges for the team’s engineers. Due to the novel approach, each part of the rover requires many rounds of testing, often with only small tweaks in between to improve the mechanisms. One of the most challenging aspects has been the rover’s nodes: These nodes help the Tumbleweed rover unfold into its characteristic spherical shape at the right time. Due to the complex design, the nodes have been a main focus in the team’s prototyping process over the past year.

Throughout the past year, the DDM engineers have been working hard to improve the structure of our rover. In July, some went the extra mile to accelerate progress on the prototyping: Ben Placke, Lead Mechanical Engineer for the DDM project, and Project Manager Nils Neumeister made the trip from Austria to join their colleagues in Delft. Especially for Nils, being back in the lab was a change of pace: “It’s been a while since I’ve been actively involved in the day-to-day engineering, so being able to actually get my hands on what we have been working on is really exciting. While being able to work remotely is in many ways a good thing, it’s very important for me to be able to see it in person as well.”

With strong leadership, Team Tumbleweed had made significant progress over 5+ years, with an all-volunteer team. 

I was drawn to be part of this Space 3.0 start-up, representing the next paradigm shift in the industry, and I joined the team as the Head of Software Engineering shortly after I finished the ISU SSP. My team is responsible for developing a unique low Size, Weight, and Power (SWaP) planetary navigation algorithm. This year, we have presented our progress at the 7th Space Resource Conference in Krakow. We have weight and processing power constraints that none of the other planetary rovers have, so we are working on unique sensor fusion algorithms.

What differentiates Space 3.0 companies from Space 2.0 is that while they also serve space agencies, the focus of Space 3.0 is mainly on private instead of government customers. While this opens up a wide range of opportunities, it also makes them financially more vulnerable because they lack an early stage institutional funding boost. 

For a startup with a long-term vision for Mars, like Team Tumbleweed, this means that it is crucial to find alternative revenue streams or investor funding to transform designs, prototypes, and simulations into reality. This is where the executives focus is, pitching to investors and attending space-related events like the 10th International Conference on Mars, the Cassini Entrepreneurship Days, or IAC24.

While this is certainly not news, the space sector continues to become increasingly relevant for the private capital, after decades of government dominance. The sector continues to see a massive growth of private investors, companies and startups in what is now called the “New Space Economy.” 

From 2005 to 2021, the global space sector has grown 2.5x, from $180B to $469. This growth is projected to continue at a rate of 11% per annum until 2030. Today, 77% of the market is commercial.

Team Tumbleweed’s vision of making deep space for everyone and opening up Mars to a whole new set of players will ensure our organization will tap into and contribute to this thriving industry.

“Women’s representation matters and it’s important to give visibility to the women moving the industry forward. I’m glad that the Women’s Aerospace Network offers a platform to echo this message,” she added. “A special thanks to the Lithuanian people for their support and my colleagues at Team Tumbleweed for working towards our bold vision of making deep space accessible to everyone.”

The Women’s Aerospace Network, led by NASA Engineer Holly Pascal, was founded in early 2024 with the mission to build a community that shares a passion for aerospace. 

“The Student Leadership award recognizes students that demonstrate exceptional leadership skills,” said Holly. “Leading an organization that is paving the road to Mars is no small feat. We’re happy to reward Onė Mikulskytė’s outstanding achievements and we look forward to seeing Team Tumbleweed reach the Red Planet under her leadership.”

Onė has received overwhelming support from peers, industry leaders, and global space organizations, but also from the broader public, especially in her country of origin, Lithuania. The country’s minister of Economy, Ausrine Armonaite,  called out to the Lithuanian people to vote for Onė, and fellow citizens made sure she was number one.

Since the award nomination, Onė has received multiple invitations from the country’s top media outlets, including the Lithuanian National Radio and Television (LTR).

However, Onė is not one to rest on her laurels. This month, she will join the International Space University’s Space Studies Program in Houston, TX, where she will continue to grow the leadership skills and industry knowledge needed to take Team Tumbleweed all the way to Mars.