It seems so long since we’ve been in the engineering buildings of the University of the Basque Country, Bizkaia campus, but thats exactly how we started our day. We took a tour through 4 different labs which Compmech (the company that works on the balancing machines from earlier this week) work in, and learnt about many different aspects of Compmechs research.

We first toured a lab in the main engineering building, which they share with another research group who focuses on sensors to measure the activity of the muscles. In one corner, they have a set up that looks like a hospital room, with furniture on loan from a nearby hospital, to ensure that the devices that they use will be easy for hospital workers to use within the limitations of the hospital. In another corner that have a camera that uses sensors to estimate the length of different segments of the body. They use this information to try and calculate the center of mass of the patient, so that they can compare it to their center of pressure. The Oreka machine, which I have talked about in previous blog posts, had been developed in this room, and they’re working on code and new features that could make it even better in not only testing patients, but also as a practice device. The first completed version of the machine went into clinical trials last week. One problem they have is differentiating between patients, since even between trials of healthy participants, there is a lot of variability in their results. They have a PhD student who is working on code on python to figure out a way to differentiate between the key signals in their results.

Compmech is trying to link the cameras and the Oreka machine together so that doctors can compare their patients center of mass and center of pressure. When patients have used Oreka, they say that the tests make them tired because it requires them to use their muscles, and if Compmech were to pair the camera with the machine, they would be able to identify the muscles being used. With the muscle groups identified, they can come up with exercises for patients to do that will activate muscles necessary for balancing or walking. The cameras they would use are made up of mostly sensors, and they don’t record the face. The program that they use only records numbers that they then use to convert to figures, as shown below, so privacy and patient confidentially isn’t an issue.

The second lab that we went to holds Compmech’s second machine, called Balance. Balance uses two independent platforms, one for each foot, to mimic the movement of walking, unlike Oreka which is intended for testing balance while standing in one spot. It moves similarly to an elliptical, but the paths are driven by motors, not by the patient themselves, and they can also choose different paths for each foot. Some patients might not be able to stand by themselves on the machine, so they have different supports that they can use. They have railings installed, so patients can be strapped into a harness, and also guides for the feet, that allow the ankle to still be free and not restrict their movement. The machine is still in development although it is mostly finished, so they are still working out little problems with the device, such as a way to route the cables so that they don’t interfere with the gears and levers as the platforms move, and a covering so that patients won’t fall through if they slip. In the case that they do fall, they have programmed Balance so that the platform stops moving if they sense a hard force on the platform, a significant weight has left the platform, or if something falls into the area under the platform. They had a similar mechanism implanted into Oreka as well. Another problem that balance has, is because it uses parallel manipulators on two different platforms, there is a chance that the computer can loose the knowledge of where the platform is. During the blackout in Spain two weeks ago, when the power came back online, it had lost the position, and they had to reset everything, and it wasn’t the only time it had happened. They can also loose control of the platforms, depending on the positioning of the two platforms, because of the parallel manipulators and the motors, since they can gain addition degrees of freedom (directional movements).

The next lab we went to focused on the manipulators themselves. We met another professor who also works at Compmech in a different focus group, and she talked to us about flexible parallel manipulators. They work similarly to parallel manipulators, but they use flexible bars connected to a moving platform and to a linear track that moves the bars. We saw two different machines that utilize flexible parallel manipulators, with the first one being like a rigid delta manipulator that moves an object from one place to another in a straight line. The second machine we saw also was for moving objects, but it had a broader range, being able to move not only side to side but also up and down. They had green tape to show us how far the plate could go, with a suction on the bottom to pick up and drop objects. She talked a little bit about the programming of the machine, which was really cool because she was using MATLAB to code and I had learnt in Engineering 0012 how to code using MATLAB. They do have a few issues with this machine however, like it vibrating slightly because of the flexible bars and how they sometimes loose the position so they have to always reset back to the starting position before doing a new task.

The last lab we went to was a machinery lab, where they had industrial machines such as a wire cutter. While we were there, they told us an interesting story about how the machines would get in and out of the basement, since that is where the lab is located. The architects of the building had originally planned for the lab to be on the third floor, but when the school heard about that they protested since all of this machinery is very heavy, and they wanted them to be located on the bottom floor. There are giant windows in the ceiling that they used to lower the machines down using a crane, and they could only work after 1 am since they had to stop the bus routes to use the crane. They added another floor to the building later, and now they can no longer use the crane, so the machines are basically stuck in the lab, unless they get them out through a small door in the back of the lab (it’s very hard to do).

After we visited the labs, we took a trip to visit the famous Hanging Bridge. Instead of a road connecting the two sides of the river, they have a gondola that moves across with a walkway 45 meters up. It it the only bridge of its kind that is open 24/7. It was really windy, even at the bottom of the bridge, and when we got to the top, it was even worse. The pathway across the bridge was made of wooden planks, and when the gondola crossed, the entire walkway was shaking. There were really pretty views though, even if it was a bit scary to cross.