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PP: Virtual Reality to Repair Spinal Injuries

Submitted by eriklee on Fri, 04/28/2017 - 12:52

His study involves patients with 3-15 years of being paralyzed by the spinal cord with partial function. He uses a three step system to model the brain signals transmitted when walking or moving around. The first step involves the patient using a virtual reality machine to control the motions of walking with brain waves. The second step puts the patient on a treadmill with mechanical legs, controlled by brain waves. The third step places the patient in an exoskeleton, similar to the one shown in the World Cup to practice walking around. The team has noted that patients have shown signs of partial recovery for the ability to emulate walking. 

Louis Pasteur and Germ Theory

Submitted by eriklee on Thu, 04/27/2017 - 18:34

In 1877, a French biologist named Louis Pasteur discovered a method of vaccination. Pasteur was able to create this vaccination due to Jenner’s works, “he mediated incessantly on the work of Jenner…” (Louis Pasteur). Pasteur was able to recognize that if Jenner could create a vaccination for an incredibly infectious disease, then a vaccine could be found for other diseases. This French biologist is an important scientist because he was able to further investigate and present the germ theory. He learned of this theory after his experiments with chicken and the poultry disease, chicken cholera. Discovering germs, what they were and how they played a role in vaccines and immunization, was crucial to get science to where it was today. With the study of germs, Pasteur was [able to better understand the infectious agent of] rabies and proceed to develop the next immunization for it. And many other vaccinations would have taken longer to come across. [Germ theory: helped scientists understand the “infectious agents of disease” and use the body’s immune system to prepare for the infection.] 

The HOPTER, the next robotic space explorer

Submitted by eriklee on Wed, 04/26/2017 - 01:26

            Landers and rovers sent to mars have several limitations, making traversing the rocky low-gravity environment difficult. Landers have a limited range of travel and rovers have trouble traversing uneven terrain, such as mountains. A new type of vehicle, known as the HOPTER, traverses land by hoping on three legs. It has a low center of gravity, high mobility, robust design, and is capable of hoping up to 4 meters in the air. This allows it to travel across mountains with ease to conduct geological surveys on the surface of Mars.

Link to Article: http://www.sciencemag.org/news/2016/01/new-space-robot-would-hop-not-drive-across-other-worlds

Meet your new coworker:

Submitted by eriklee on Mon, 04/24/2017 - 22:52

Baxter is a $25,000 humanoid robot designed by Rethink Robotics. The company’s goal is to design robots that combine human psychology and robotic engineering together. By doing this, the company intends to create smarter robots with the ability to learn from humans and complete repetitively mind-numbing tasks. Baxter is described as a female robot named after female bakers. John Bohannon tested Baxter by instructing her to move objects from a crate to a conveyor belt. To do this, John had to grab the robots hand a transfer an item from the crate to the conveyor belt. Additionally, he had to outline boundaries for the starting and stopping destinations. Baxter is capable of repeating the task after the first demonstration with one drop.

            Beyond completing repetitive tasks, Baxter is programmed to display six emotions ranging from tiredness to surprise. These facial expressions are shown on a monitor displaying digital eyes. The robotic arms and body shift to match the expression. The designers hope to improve safety and improvisation within robots to make them behave like humans. There are several monitors and switches that protect the robot from accidentally or intentionally harming a human nearby.  However, the improvisation has been limited as there needs to be more work on what psychologists call the Theory of Mind. Furthermore, Baxter and many other robots have limited mobility, especially upstairs.

Link to Article: http://science.sciencemag.org/content/346/6206/180.full

PP: Artificial Touch

Submitted by eriklee on Fri, 04/21/2017 - 12:12

The task of the two patients of the study describe how electrical stimulation is distinct at varying levels of intensity. The researchers developed a value known as activation change rate (ACR) that represents the “total population spike count in the activated neural population.” It measures the aggregate intensity of the neurons in width and amplification to get a sense of how intense each iteration of electrical stimulation is perceived as. They found that population spikes in nerves correlate with the magnitude of touch. 

Virtual Reality to Repair Spinal Injuries

Submitted by eriklee on Fri, 04/21/2017 - 01:29

                In the 2014 World Cup, scientists were able to construct an exoskeleton that allowed a paralyzed individual to kick a soccer ball. Since then, Miguel Nicolelis and his team at Duke University have tried this same methods to restore the connection between the brain and muscles following a spinal cord injury. But instead of bypassing the spinal cord and creating a direct connection between the brain and muscles, Nicolelis’ team has used implanted electrodes or noninvasive EEGs to transmit signals from the brain to a mechanical prosthetic.

            His study involves patients with 3-15 years of being paralyzed by the spinal cord with partial function. He uses a three step system to model the brain signals transmitted when walking or moving around. The first step involves the patient using a virtual reality machine to control the motions of walking with brain waves. The second step puts the patient on a treadmill with mechanical legs, controlled by brain waves. The third step places the patient in an exoskeleton, similar to the one shown in the World Cup to practice walking around. The team has noted that patients have shown signs of partial recovery for the ability to emulate walking.

Link to Article: http://www.sciencemag.org/news/2016/08/robo-suit-and-virtual-reality-reverse-some-paralysis-people-spinal-cord-injuries

Artificial touch part 1

Submitted by eriklee on Wed, 04/19/2017 - 01:14

A study conducted by Graczyk et al. looked at stimulation of different nerves of the arm and hand via electrodes to understand how intensity of touch is perceived and transmitted. The study followed two amputees who have permanent electrodes implanted in the somatosensory nerves. The study tries to understand how varying frequency of stimulation and population size of stimulated neurons correlates with the intensity of gripping an object.

            The task of the two patients of the study describe how electrical stimulation is distinct at varying levels of intensity. The researchers developed a value known as activation change rate (ACR) that represents the “total population spike count in the activated neural population.” It measures the aggregate intensity of the neurons in width and amplification to get a sense of how intense each iteration of electrical stimulation is perceived as. They found that population spikes in nerves correlate with the magnitude of touch.

Link to Paper: http://stm.sciencemag.org/content/8/362/362ra142.full

Dilemma for Automated Cars

Submitted by eriklee on Thu, 04/13/2017 - 01:31

            On major issue in the design of automated cars is their ability to handle unavoidable accidents involving the passengers and pedestrians. A study conducted by researchers sought to understand which types of algorithms can handle such acute situations. They created three different scenarios, indicated by Figure 1 from the study. In the first, an automated car had to choose between hitting one passenger or a crowd of passengers. In scenario two, an automated car had to choose the passenger or a single pedestrian. In scenario three, the automated car had to choose between saving the passenger or a crowd of pedestrians. These scenarios have a low probability in actual driving. But multiplied over a global scale, the instances of these accidents are significant, especially if many people are driving automated cars. Thus, it’s important to design algorithms that minimize loss in every scenario conceivable and prepare automated cars to perform the morally “correct” action.

            In the study, the researchers believed that algorithms, dictating the decision making of the car, depend on collective moral reasoning. After all, a machine cannot decide what is right or wrong. It is up to the designers and consumers, who will purchase the vehicles, to decide which algorithms suit safety standards. The current idea and design focuses on the use of utilitarian vehicles, which consistently choose to sacrifice the passenger for the pedestrians. However, this contradicts the value of automated cars for consumers, if they are buying cars that do not guarantee their own safety.

            All of the studies conducted surveyed a group of U.S. drivers and used statistical analysis to refine and produce precise results. The first study asked participants on a scale whether they prefer cars that save the passenger or 10 pedestrians. A majority chose in favor of the pedestrians, reasoning that saving more lives is the right thing to do. The second study varied the number of pedestrians from one to many. It found that one pedestrian is not worth sacrificing the driver. But as the number of pedestrians increased, the results favored the pedestrians. The third and fourth studies asked if participants were willing to buy automated vehicles and which algorithms they preferred. The third study found a low likelihood in purchasing utilitarian vehicles, especially when the scenario involved a family member. Further, participants consistently ranked algorithms, which saved more pedestrians, higher than the “selfish” algorithms.

            These studies do showcase a dilemma for automated cars. Participants have shown to have preference in saving the pedestrians over passengers. However, the self-sacrificing car does not sit well with potential purchases. Until the algorithms can be refined well, to a point where it can calculate risk and save both passengers and pedestrians, it does not seem automated driving will hit the road in the near future. Not to mention, there are a lot of ethical and legal decision making behind the safety of automated cars.

Link to article: http://science.sciencemag.org/content/352/6293/1573.full

Robotic Stingray made from Rat Heart

Submitted by eriklee on Tue, 04/11/2017 - 17:44

A real life Victor Frankenstein, Kevin Kit Parker, of Harvard University, and a team of post-doctorate researchers have designed a preliminary robotic stingray made from rat cardiac muscle cells. Parker mentions his interest in the biomechanical creation coming from his daughter’s encounter with a stingray at the Boston Aquarium. Couple with his interest in the mechanics of a mammal heart, Parker wanted his team to implement the pump-like action of a jellyfish, using heart muscle cells, on a stingray body plan. The result is a 200,000 cell large stingray the size of a dime.

            Parker and his team designed the artificial creature by harvesting 2-day-old rat myocardial stem cells. These were placed on a silicon surface enriched with sugar and salt-ions and kept at the body temperature of a rat. The silicon surface has various proteins such as extracellular matrix and fibronectin to guide the growth of cells into the sting ray shape. The outer body of the stingray consists of an elastomer body made of cardiomyocytes and adhering proteins. The skeleton is made of gold and is surrounded by a responsive network that propagates signals in a serpentine patter down the anteroposterior axis of the body.

            A virus was used to deliver genes to code for light responsive proteins. When expressed in the myocardial cells, specific wavelengths of light can trigger a signal cascade, causing the muscle to contract. Blue light allows the stingray to travel 9 meters per hour. Variations in the wavelength can cause it to swim faster or slower. Additionally, the two serpentine networks allows the left fin to move independently from the right fin so the stingray can turn.

            This creation is another big step for the integration of biology and robotics. The stingray helps understand how myocardial cells interact with the environment and can be genetically engineered. This provides insight into the possibility of creating artificial hearts and artificial organisms.

Video Link: https://youtu.be/-D_XrRo0h20

Article Link: http://www.sciencemag.org/news/2016/07/robotic-stingray-powered-light-activated-muscle-cells

Iron Man Exo Suits TALOS and HULC

Submitted by eriklee on Mon, 04/10/2017 - 19:21

The most recent iterations of the Call of Duty video game series, since Advanced Warfare and Black Ops III have updated the weapon and armor arsenal to include exo suits. In the games, the exoskeletal suits improve endurance, strength, and include features such as speed, flight, and 3 dimensional traversal. While Call of Duty has been envisioning the future of weapon technology, the current implementations of a robotic suit can only be described as primitive. The U.S. military and various partnered research agencies have launched several exo suits that have fallen short due to physiological limitations.

            One popular robotic suit, developed by the U.S. military, named TALOS (Tactical Assault Light Operator Suit), was developed for Special Operations. The suit was described to provide improved strength, bullet protection, and monitor vitals. A predecessor to TALOS, nicknamed HULC (Human Universal Load Carrier) has recently been tested in a military base at Natick, MA. The designers described the tactical suit provides improved strength, endurance, protection. However, expectations fell short as the suit proved more problematic than helpful. During tests, subjects encountered increased physiological constraint by increasing heart rate and oxygen consumption.

            Currently, there are two versions of the exoskeleton: rigid and soft. The TALOS and HULC have been new versions of rigid exoskeletons. These consist of a mechanical frame with motorized joints. Heavy suits have the benefit of carrying the cargo that normally encumbers soldiers. The downside this consumes a lot of power and its performance is exhausting to soldiers. However, companies are currently focused on developing soft skeletons, which consist of a smaller motor, fabrics, and cables. These provide limited boost in speed and endurance. But it has limited mobility traversing uneven terrain and does not support the extra weight. 

Link: http://www.sciencemag.org/news/2015/10/feature-can-we-build-iron-man-suit-gives-soldiers-robotic-boost

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