Issue link: https://iconnect007.uberflip.com/i/1093246
54 DESIGN007 MAGAZINE I MARCH 2019 van der Marel: It started four years ago. Some other group initialized this exoskeleton proj- ect, and there were enough enthusiastic stu- dents who wanted to dedicate a year to build- ing this exoskeleton. After that year, they con- tinued their studies and recruited a new team of students to make an improved version. That has continued to this year. Shaughnessy: Did you have to do your own fun- draising to find the money necessary for this? van der Marel: We find sponsors each year to do our own funding because we are self-depen- dent. We have dedicated people who attend events, find partners, and raise enough money to build an exoskeleton each year. Shaughnessy: Approximately how much does it cost to build one of those? van der Marel: It's kind of hard to estimate, but I can tell you that commercial exoskeletons cost approximately €80,000 or US$90,000. For us, we do not have the intention of selling our exoskeleton at this moment, so it's not really possible to put a price on it. Right now, we're focused on the development of the technolo- gy. We hope that in the future, the exoskele- ton will be accessible for everyone who could benefit from it. After the competition, we retire them and use them for tests for the next year. Shaughnessy: Roy, can you tell me about the circuit boards and the technology that goes into this exoskeleton? Roy Arriens: We have multiple circuit boards in the exoskeleton that revolve around power management, data collection, and controlling the instrument itself. We primarily have three types of boards in our exoskeletons. One is the power distribution board, which distributes all the power from our main battery to all the dif- ferent kind of types of joints. Next, we have the data collection architec- ture, which is EtherCAT. We use EtherCAT to collect all of the data from the motor control- lers, power distribution boards, and other types of sensors in the skeleton. And we have motor controllers, which are iMOTIONCubes, and we make our own PCBs for that, so it's a moth - erboard for this motor control- ler. We connect it with EtherCAT to different kind of boards called general EtherCAT slaves, which we use to interface with, for ex - ample, temperature sensors. We designed the power distribution board ourselves. For the slaves, we buy the motor controllers and design the motherboard in- house. Shaughnessy: And you use Alti- um tools? Arriens: Yes, primarily for the power distribution board. We design the whole PCB in Altium from schematics to layout. Shaughnessy: And did you have access to Altium in the school? Is that how you were exposed to it? Martijn van der Marel and Roy Arriens.