In this short series we speak to the designers and engineers who created our hero projects at Bett Show 2019, to find out how they built them and what problems they overcame.
Choudhry Amjad is a software developer at pi-top, and worked on the programming for our mini Mars rover.
"So to get this working, we needed to program the motors, the arms, and also we have the data collection, which is shown on a webpage. I worked on the motors and getting all of the different programs working together on the same pi-top and some of the networking stuff." says Choudhry.
Designing and fitting the motor parts was fairly straight forward, but the robotic arms proved much trickier. "Another one of my colleagues worked on that and he had to uses quite a bit of inverse kinematics to actually get the arms to work." Choudhry explained.
The arm on the rover is controlled by, and mirrors the movement of, another arm on the workbench next to the display area. Moving one arm, moves the other. Although the lag over the show's wifi was around a second, the lag between Earth and Mars would be over 13 minutes.
The other key thing about our mini Mars rover is that it collects data. Another member of the team worked on that, as Choudhry explains, "what he did was a really interesting and smart way of displaying it. He has the data collected and instead of just showing you on the screen, he has it sent to our webpage. This means that anyone in the local network could just look at the data, which is very accessible. "
Two of the biggest problems
Like all the hero projects, there were issues to overcome. "There were two big problems," Says Choudhry. "One was the inverse kinematics on the arms was very complicated for the engineer to go through. Other people also chipped in and helped him with that and eventually, we got that going."
"The second problem was when we got to Bett. The network is so atrocious. I was paranoid to leave the standing even to talk to someone for too long or to go too far out in case something breaks and I need to go back and fix the network."
The rover was a huge hit with Bett attendees and was very popular. "A lot of people are coming here taking pictures. Even the Bett people, everyone's coming here recording the pictures of this. This is almost becoming the centrepiece of where everyone is looking at."
This was quite unexpected for Choudhry, "I haven't really done a project that many in the outside world got to see, and I certainly haven't done much robotics work, as most of my projects are software engineering base, like video games and stuff like that."
"This being a robotics project, which I worked on and which people are enjoying here in the wild basically, has inspired me to actually do more in robotics."
Next steps
But Choudhry and the team aren't stopping there. "We could land on Mars! It's pretty cheap, it's fully 3D printed the service motors and all the parts that we have to buy aren't that expensive. We could shoot a couple of hundred to Mars and still not scratch our wallets. And we can do a lot of testing there!"
And with Opportunity out of action, we hope we've done enough to inspire the next generation of rover engineers and scientists.
Spent the evening at JPL as the last ever commands were sent to the Opportunity rover on #Mars. 💔
— Dr. Tanya Harrison (@tanyaofmars) February 13, 2019
There was silence. There were tears. There were hugs. There were memories and laughs shared.#ThankYouOppy #GoodnightOppy pic.twitter.com/JYRPtKZ8T5
