Guest Blog: Mission to Mars
Earlier this year, a team of engineering and computer science students from the University of Sheffield travelled to Poland to take part in the European Rover Challenge (ERC), a competition where teams are tasked with designing and building rovers for space exploration.
Mechanical engineering student Alistair Mitchell was part of The University of Sheffield MarsWorks Team and in his guest blog, he shares more about the build up to competition, what it’s been like to design a Mars rover and future plans for the project.
In September 2019 I found myself in Poland, taking part in the European Rover Challenge (ERC) as a member of the University of Sheffield MarsWorks team.
It was the first year our team had entered the competition and after many hours of design and manufacture behind us - as well as our fair share of challenges and compromise – we made our way to Kielce with high hopes for testing out our Mars rover design.
Going to competition meant that, as a team, we had to design and build our rover so that it could complete a series of tasks in a simulated Martian terrain. The tasks covered navigation, automation, excavation, dexterity and level of control, necessitating the need for three major systems in our design: chassis-locomotion, a robotic arm and a subsurface excavator (in our case a drill).
Alongside the physical side of the engineering, there were also written tasks and other deadlines, taking the form of a preliminary design report, complete with estimated costings and proposals for subsystems and general operation. We pulled together a promotional video, which also illustrated the level of progress we've made in building our rover.
A final report detailing our design choices and a breakdown of our systems was also developed in time for competition, as well as a group presentation that we had to deliver to judges as part of the weekend in Poland. This covered issues we had come across, management structure, feasibility, and other points of interest.
All in all, we had a very busy time preparing for Poland!
Down the Rabbit Hole
I first came into the MarsWorks project relatively late, about three months before we were due to head out to the competition in Poland.
I initially got involved via a friend, who asked if I wanted to help him and the team design the rovers’ wheels. This was something I was keen to get involved in and after helping with the wheels, I went on to support some additional design work on other subsystems too.
This naturally led me to become much more involved in the whole project and competition team – in particular, assisting with the designs for the suspension and wheel fork assemblies, the 5th degree of freedom (DOF) for the robot arm, and various mounting solutions for subsystems.
It was a crash course in understanding what the project was all about and I also started to realise the scale of what the team was trying to undertake – it was exciting to be able to take part in it all and put my engineering design skills into practice.
Getting to competition
As our design and build came together, we started to prepare for the competition weekend itself. The plan was for two members of the team, as well as our academic supervisor Viktor Fedun, to drive from Sheffield to Poland with the rover, with the rest of the team flying over and joining us there.
In total seven team members were able to make the trip to Poland and in the weeks leading up to the event, it was a frenzy of activity as each sub-team worked down their checklists of things to do.
As to be expected, problems were found along the way, but as a team we focused on finding solutions. At this stage most of the mechanical work on the rover was complete, however, the electrical sub-team and the control sub-team had their work cut out in trying to get various systems to communicate. In the end, we packed up the rover for competition without yet seeing all four wheels spinning at the same time. Not the ideal scenario!
However, we ploughed on and as one of the team members who drove the rover over to Poland, the next few days were a blur of ferry trips and driving as we travelled from Hull to the Netherlands, from the Netherlands into Germany, and then halfway across Poland to the city of Kielce – an epic 1440km in total.
We got there in the end though and one of the first things to do was assemble the rover – quite an experience in a cramped hotel room! As competition was just a couple of days away, we then continued the preparations we had been undertaking in Sheffield, chasing down faults and trying to get key systems working.
Challenge and Competition
Competition was soon only hours away and we worked both day and night with varying success to get our rover competition-ready.
During this preparation time, our electrical team managed to get the wheels turning in some fashion, as well as eliciting some movement from the robot arm, which was a massive step forward. Yet despite this leap forward, we ultimately had to be pragmatic and cancel our first task of the competition as we knew we would not stand a chance at completing it.
However, we had the rest of the competition to focus on and the following day was the start of the judging weekend. Although we hadn’t quite achieved what we were hoping to by this point, spirits were still high and we were all learning a lot.
The competition itself started on a positive note, with our presentation task going extremely well with good feedback from judges – all leading to the general team feeling that not all had been lost up to this point.
Overnight, we made major progress in our preparation for our second day of competition with the wheels now turning on demand and the rover now wirelessly manoeuvred via an Xbox controller. This meant we were allowed the opportunity to take our rover for a spin on the simulated Martian terrain despite not being able to complete all of our earlier tasks.
It was an amazing chance to see the culmination of our hard work and our rover performed admirably, making quick work of rocky obstacles. Our suspension responded far beyond what we thought it would achieve too. We chalked this up as a success.
The following day came the third and final day of competition and we worked to learn as much as we could and improve upon our successes, largely in the form of talking with other teams and discussing their designs. This was an invaluable experience as it really opened our eyes to alternative design approaches. We also saw first-hand what did and didn’t work in the field.
In the end, not much progress was made on the final day, but we did get to prove the mechanical strength of the rover by driving it around with a person stood on it!
I’ve learnt so much from this experience, not just about the engineering required to undertake a project like this, but also about management and communication. It has been an invaluable experience and I’d definitely recommend other students to get involved in projects like this.
The team as a whole is bristling with new ideas for next year’s rover, and with the continued help of the iForge and the mechanical engineering department workshop, we’re aiming to really build on what we have learnt and design a rover that can truly provide some stiff competition for next year’s event.
Bring it on!