Ventilators are key in the treating the most dire cases of coronavirus. The exponential growth of infections, and the number of patients in respiratory distress, has outpaced the number of available ventilators. In times of crisis, everyone looks for ways they can help, and one of the ways the hardware community has responded is in work toward a ventilator design that can be rapidly manufactured to meet the need.
The difficult truth is that the complexity of ventilator features needed to treat the sickest patients makes a bootstrapped design incredibly difficult, and I believe impossible to achieve in quantity on this timeline. Still, a well-engineered and clinically approved open source ventilator might deliver many benefits beyond the current crisis. Let’s take a look at some of the efforts we’ve been seeing recently and what it would take to pull together a complete design.
Continue reading “What Does A Dependable Open Source Ventilator Look Like?”
When you put a human driver behind the wheel, they will use primarily their eyes to navigate. Both to stay on the road and to use any navigation aids, such as maps and digital navigation assistants. For self-driving cars, tackling the latter is relatively easy, as the system would use the same information in a similar way: when to to change lanes, and when to take a left or right. The former task is a lot harder, with situational awareness even a challenge for human drivers.
In order to maintain this awareness, self-driving and driver-assistance systems use a combination of cameras, LIDAR, and other sensors. These can track stationary and moving objects and keep track of the lines and edges of the road. This allows the car to precisely follow the road and, at least in theory, not run into obstacles or other vehicles. But if the weather gets bad enough, such as when the road is covered with snow, these systems can have trouble coping.
Looking for ways to improve the performance of autonomous driving systems in poor visibility, engineers are currently experimenting with ground-penetrating radar. While it’s likely to be awhile before we start to see this hardware on production vehicles, the concept already shows promise. It turns out that if you can’t see whats on the road ahead of you, looking underneath it might be the next best thing. Continue reading “Navigating Self-Driving Cars By Looking At What’s Underneath The Road”
Most often, humans and robots do not have to work directly together, instead working on different parts in a production pipeline or with the robot performing tasks instead of a human. In such cases any human-robot interaction (HRI) will be superficial. Yet what if humans and robots have to work alongside each other? This is a question which a group of students at MIT’s Computer Science and Artificial Intelligence Lab (CSAIL) have recently studied some answers to.
In their paper on human-robot collaborative tasks (PDF), they cover the three possible models one can use for this kind of interaction: there can be no communication (‘silent’), the communication can be pre-programmed (state machine), or in this case a Markov model-based system. This framework which they demonstrate is called CommPlan and it uses observation data from human subjects to construct a Markov model that can integrate sensor data in order to decide on its next action.
In the experiment they performed (the preparation of a meal; see the embedded video after the break), human subjects had to work alongside a robot. Between the three different approaches, the CommPlan one was the fastest, using voice interaction only when it deemed it to be necessary. The experiment’s subjects expressed hereby a preference for bidirectional communication, much as would occur between human workers.
Continue reading “Teaching Robots Workplace Etiquette”
In many parts of the world the COVID-19 pandemic is causing shortages in hospital space, staff, medical supplies, and equipment. Severe cases may require breathing support, but there are only so many ventilators available. With that in mind, MIT is working on FDA approval of an emergency ventilator system (E-Vent). They have submitted the design to the FDA for fast track review. The project is open source, so once they have approval the team will release all the data needed to replicate it.
The design is actually made simple by using something that is very common: a manual resuscitator. You have doubtlessly seen these on your favorite medical show. It is the bag someone squeezes while the main character struggles valiantly to save their patient. Of course, having someone sit and squeeze the bag for days on end for thousands of people isn’t very practical and that’s where they’ve included an Arduino-controlled motor to automate the process.
Continue reading “MIT Ventilator Designed With Common Manual Resuscitator; Submitted For FDA Testing”
Most of us know that to get the best possible WiFi signal, you want there to be as few walls as possible between you and the Access Point. But that might soon change, as researchers at MIT have found a way to make surfaces increase signal strength. Called RFocus, the technique uses a wall panel covered in simple antennas to dynamically focus or reflect RF energy towards a intended receiver.
The normal methods to increase wireless range usually involve increasing the transmitter output or adding larger, more efficient, or directional antennas to the receivers and transmitters. But these techniques are limited when you need to the reduce power consumption and size of the devices. The MIT teams approached the problem from a completely different angle, by optimizing the environment.
The wall panel in question consist of 94 PCBs, each containing 40 passive antenna elements in the form of copper rectangles. Each element is a quarter wavelength long (125 mm for 2.4 Ghz), and on its own it doesn’t have any real effect on the signals, allowing it to pass through the panel. Between the ends of elements are small RF switches, that can close to combine two antenna elements into single half wavelength antenna, creating a reflector. When this is applied across the panel in different patterns it can effectively beamform the signal to focus it at different points in space.
The RF switches are connected to shift registers, which are all controlled via a single SPI bus with an Arduino. Each RF switch is activated in a pseudo-random sequence, changing the configuration of the panel 10,000 times in 100 ms. The signal strength at the receiver is reported to the panel controller for each configuration, allowing the controller to select the best configuration for any single transmitter. In a scenario where multiple low-power sensor nodes are deployed, this can allow the receiver to “focus” on each node in turn. The full paper is a very interesting read, downloadable as a PDF.
RF is generally considered the black magic of electronics, but it can all become a bit clearer with a basic knowledge of antenna theory and modulation schemes.
Thanks to [Qes] for the tip!
Dealing with an antenna is one of those topics we never feel like we know enough about. MIT had a live stream of [Dr. Kiersten Kerby-Patel] discussing antennas in a talk, sponsored by the ham radio club on campus. You can see the recording below.
The main assertion of the presentation is that everything is a dipole unless it is a loop. Although the professor probably deals with antennas at an extremely high theoretical level, she did a great job of keeping it aimed at ham radio operators.
Continue reading “Ham Antennas From MIT”
We nearly passed over this tip from [xoxu] which was just a few links to some AliExpress pages. However, when we dug a bit into the pages we found something pretty surprising. Somewhere out there in the wild we…east of China there’s a company not only reverse engineering the Mini Cheetah, but improving it too.
We cover a lot of Mini Cheetah projects; it’s a small robot that can do a back-flip after all. When compared to the servo quadruped of not so many years ago it’s definitely exciting magic. Many of the projects go into detail about the control boards and motor modifications required to build a Mini Cheetah of your own. So we were especially interested to discover that this AliExpress seller has gone through the trouble of not just reverse engineering the design, but also improving on it. Claiming their motors are thinner and more dust resistant than what they’ve seen from MIT.
To be honest, we’re not sure what we’re looking at. It’s kind of cool that we live in a world where a video of a research project and some papers can turn into a $12k robot you can buy right now. Let us know what you think after the break.