ATTI speaks to Kent Persson, technical specialist at NEVS, about the Sango self-driving electric robotaxi program and some of his most memorable moments to date
Please could you tell us a little about your career background and your role at NEVs.
I have worked in vehicle testing for 25 years focusing on electronics among other things, such as body functionality and infotainment. Having previously worked with normal combustion engine cars and trucks for seven years, at NEVS my role focuses on electric vehicle tech. Being the first person to drive a completely new vehicle is very exciting, and it’s a job that needs someone who knows what they are doing or someone who is crazy – I joke that I am the latter.
When did the Sango’s development begin, what stage are you at now and what’s been your most memorable moment so far?
Development of the Sango started two years ago, and the first rolling road tests were conducted in summer 2020. Right now we are testing the AV’s functionality and stability, and this will cover numerous scenarios, specifically the ones we may face on public roads. We are currently in the process of trying to obtain government approval to begin trials on public roads in Stockholm in 2022.
In terms of memorable moments, there are a couple of them to be honest, but I think it was the very first time that I started to drive the Sango with a joystick. The first moment when we used it – for me at least – was very different [to any kind of driving I had ever done]. To actually see it become a drivable vehicle; I think for me, that was the most exciting moment.
How did you develop the joystick adaption that enables the unmanned vehicle to be driven, and how did the early tests go?
The joystick enables the vehicle to be moved remotely in all directions – forward, backward, to the right and to the left. After the initial tuning we had to refine it further to ensure smooth control of the vehicle. You don’t want the steering to be too quick or too slow, and you also want the vehicle to gradually build speed. It needs to crawl from stationary with smooth and controlled movements [when using the joystick], which was the target.
With AVs being in their infancy, has the testing thrown up any unexpected challenges?
When we started this project there were lots of new things we had to consider. Should we have a safety driver in the car? How can we move the vehicle autonomously? If we were to have a safety driver, this would mean having someone in the actual vehicle. Then we decided a joystick combined with a driver in the vehicle was the way to go. Lots more questions were raised around the fact that a driver would be used to having a steering wheel, a brake pedal and an accelerator, and now all they have is this joystick.
In the beginning, the focus was the safety of the driver and then we started to look at passenger safety. Firstly and most importantly, it needs to be safe. It needs to feel safe for passengers to enjoy the ride, and therefore it was important to have this smooth control with the joystick.
Other questions that we asked ourselves were: What should happen if the safety driver needs to press the emergency button? Should it use the maximum breaking force? Would it be possible to steer around [the danger]? Should the vehicle maintain its direction if it is on a bend? When the vehicle first goes into use on public roads, the Swedish authorities require us to have a safety driver and an emergency stop button.
What is the key to a successful test program?
It’s about learning, every day, learning from what you have done previously. You should always be thinking about what was good, what can be done better next time, how you can do things a different way – this applies to the software loops, the physical test loops and future projects – and that’s for all types of vehicles.