UC San Diego engineers develop a smart mouth guard

---

Researchers have developed an integrated wireless mouth guard biosensor for real-time monitoring of health markers in saliva.

---

Engineers at the UC San Diego have developed a smart mouth guard capable of monitoring health markers, such as lactate, cortisol and uric acid, in saliva and transmitting the data wirelessly to a mobile device. The idea is that, one day, the technology could be used to keep tabs on patients without invasive procedures, as well as track athletes’ performance or stress levels in soldiers and pilots.

The study, which was led by UC San Diego professors Joseph Wang and Patrick Mercier, focused primarily on uric acid, which is a marker related to diabetes and gout. Currently, the only way to monitor these levels in a patient are through blood tests. Wang explains, “The ability to monitor continuously and non-invasively saliva biomarkers holds considerable promise for many biomedical and fitness applications.”

The team of researchers developed a screen-printed sensor using silver, Prussian blue ink and uricase. To ensure that the sensors only reacted with the uric acid, the nanoengineers had to set up the chemical equivalent of a two-step authentication system. The first step involves a series of chemical keyholes that allows only the smallest biochemicals to enter inside the sensor. The second step is a layer of uricase trapped in polymers. The reaction between acid and enzyme generates hydrogen peroxide, which is detected by the Prussian blue ink.

That information is then sent to a circuit board as electrical signals via metallic strips that are part of the sensor. The board, which is no much bigger than a penny, is equipped with a microcontroller, a Bluetooth Low Energy transceiver, and a potentiostat. These small chips detect the sensor output, digitizes it and wirelessly relays the data over to a smartphone or computer.

Thus far, the researchers have been able to show that the mouth guard sensor could offer an easy, more reliable way to monitor uric acid levels; however, it has only been tested with human saliva and not yet actually in a person’s mouth. Looking ahead, the team plans to embed all of the electronics inside the wearable device so that it can be worn. This process will entail testing the various sensors and electronic materials to ensure their biocompatibility.

The next iteration of the mouth guard is expected to be completed in a year or so. Until then, you can read all about the study in its recently published article in Biosensors and Bioelectronics.

(Image: UC San Diego, Jacobs School of Engineering)

This 3D-printed robot can jump six times its height

---

This first-of-its-kind, autonomous robot blasts off like a UFO.

---

In a paper published Thursday in Science magazine, engineers from Harvard University and the UC San Diego have revealed a 3D-printed, autonomous robot capable of over 30 untethered jumps without connection to an external computer or power source. Actuated by a combination of butane and oxygen, this little bot can leap two and a half feet into the air — up to six times its body height.

(Source: Harvard Microrobotics Lab)

Inspired by nature, the project uses the combination of both hard and soft materials which its designers say make it a more efficient jumper. For example, certain species of mussels have a foot that starts out soft and then becomes rigid at the point where it makes contact with rocks.

“In nature, complexity has a very low cost,” explains Michael Tolley, an assistant professor of mechanical engineering at UC San Diego. “Using new manufacturing techniques like 3D printing, we’re trying to translate this to robotics.”

Soft robotics is surely a hot topic at the moment, as engineers are finding them to be much more adaptable and resilient than their conventional, metal-based counterparts. However, their flexibility comes at a coast: they tend to be slower, more difficult to fabricate and challenging to make autonomous due to the fact that most motors, pumps, batteries, sensors and microcontrollers are rigid.

Fortunately, the joint research project has come up with a design that offers a new solution to this conundrum by integrating hard and soft materials. In other words, the best of both worlds.

The combustion-powered robot is comprised of two hemispheres: a soft, plunger-like body with three pneumatic legs at the bottom and a 3D-printed, sturdy core on top. The latter houses a custom circuit board, a high-voltage power source, a battery, a miniature air compressor, a butane fuel cell, six solenoid valves, an oxygen cartridge and pressure regulator and ducts to move the gas and stuff around as necessary. What’s more, it has nine graduating levels of stiffness.

(Source: Science)

In order to determine the perfect gradient of firmness, researchers tried a couple prototypes. And what they found was that a fully rigid top would make for higher jumps, while a flexible top was more likely to survive impacts on landing, allowing the robot to be reused.

For movement, the robot inflates its pneumatic legs to tilt its body in the direction that it wants to go. From there, butane and oxygen are mixed together and ignited, catapulting it into the air like a UFO. Once the chemical charge is exhausted, the bottom hemisphere goes back to its original shape. Researchers say that the robot’s jumping ability and soft body can come in handy in harsh and unpredictable or disastrous environments, enabling it to survive large falls and other unexpected situations.

In a series of tests, the robot was able to leap two and a half feet in height and half a foot laterally. Beyond that, it jumped more than 100 times and survived an additional 35 falls from a height of nearly four feet.

Interested? Read the project’s entire article here.