July 20, 2017

Soft Exosuits: Science of Fictional to Real life suits


Behind Crysis' Nanosuit

       When you step into one of the games in the Crysis series, you step into something called a "Nanosuit." It makes you a stronger, better soldier.
       The Nanosuit is supposedly made up of a material called CryFibril, also referred in the game as Nanoweave or Nanofiber. CryFibril is the single most important component of the suit, as it is the medium for the various Nanosuit functions. In Crysis 2, the CryFibril got a major overhaul, making the Nanosuit lighter, stronger and more energy efficient.
        Someone at Crytek must have been doing their homework because CryFibril looks suspiciously like a recent real-world breakthrough in nanomaterial technology.

        Coincidence? I think not—CryFibril on the left and nanoscale carbon (graphene) on the right

CryFibril—fabric of the future or is it already here?

        Graphene (pictured above) is a one-atom thick sheet of carbon arranged in a repeating hexane pattern that has some really amazing mechanical properties.
Well in short, graphene is one the strongest materials ever manufactured. It has a breaking strength 100 times greater than steel and weighs thousands of times less (10,194 times less to be exact). Graphene can be rolled up into tubes, called carbon nanotubes, which are even stronger than graphene sheets. Carbon nanotubes can then be spun together and woven into fibers which are much more flexible and useful as engineering materials, making them the ideal fabric for the Nanosuit. If you can believe it, carbon nanotubes are even harder than diamond. So it comes as no surprise that research is already underway towards developing carbon nanotube composite body armour for police and military applications as well as building an elevator to space, just to name a few ideas.

       Graphene can be rolled up into a tube just like a sheet of paper and spun into super strong carbon nanofibers, the perfect material for an armoured Nanosuit.

Maximum Armour

         In a pinch, Prophet can divert power to the CryFibril Nano suit armour to temporarily increase protection from incoming high-speed objects, blunt trauma and energy blasts. This process, called Armour Mode, supposedly tightens up the suit's outer weave, which decreases the suit's power upon impact, rather than valuable health.
         Interestingly, there is a real world nanomaterial counterpart currently under development called D30 gel. This protective nanogel is a dilatant non-Newtonian fluid, which is a very fancy way of saying it is flexible when moving slowly, but rigidifies upon impact, before quickly returning to its flexible state again. These types of materials behave very strangely. Studies have down that D30 gel can absorb much of the energy from a shock or impact, greatly reducing the damage to the wearer. It is already in use in protective sports equipment and is coming soon to a battlefield near you.

Shock-absorbing nanogel (D30), real life Maximum Armour

Maximum Power

          When Prophet needs to quickly sprint across the battlefield, leap to cover on top of a Pinger or toss a wrecked car at a pesky group of Ceph, Power Mode is the way to go. Power Mode uses up Nanosuit energy for as long as it is active and grants the player superhuman strength.
          How can we rationalize this with some real world science? Well, we could talk about a powered exoskeleton like the Raytheon XOS. This would fit the bill in terms of Power Mode functionally but it is hardly a nanoscale technology. No, we need to go smaller, much smaller.
          An international team of researchers lead by Ray Baughman at the University of Texas have come up with a nano-sized alternative. They have developed an artificial nano fiber muscle. These nano fibers are made up of ropes of carbon nanotubes which are twisted together into thicker yarns and set into paraffin wax.
The bundles of nano fibers can contract rapidly when exposed to heat or electricity, up to 200 times stronger than human muscle. The manufacturing process will have to be improved to weave larger fabrics, like our trusty Nanosuit, but the basic premise checks out.

Ropes of carbon nanotubes can be spun into thicker yarns forming high strength artificial muscles.

Soft exosuits flexible fabric exoskeleton

1. Robo Glove

A Better Grip on Earth, in Space -2013 R&D 100 Winner Robo-Gloves

       NASA’s Johnson Space CenterGeneral Motors and Oceaneering Space Systems have partnered to design a solution: the Robo-Glove as a spin-off technology from Robonaut.
        Humans are designed to grasp well; but repetitive, high-force gripping can result in long-term discomfort or injury. For example, an assembly operator in a factory might need to use 15 to 20 lbs of force to hold a tool for a task. These tasks typically have to be performed every 30 to 40 seconds and require both high levels of dexterity and hand strength.
          This human grasp-assist device augments the grip of a human hand using linear actuators and high-strength polymer tendons. Pressure sensors built into the fingertips of the glove detect when the user is grasping a tool or object. The synthetic tendons automatically retract, pulling the fingers into a gripping position and holding them there until the sensor is released.                   
            Force-based contact sensors positioned at the distal end of each finger offer control for the user. Pressure on the sensors triggers the execution of an algorithm by a microcontroller that determines the optimal amount of augmenting tensile force.

           In addition to getting more grip with less pressure, the RoboGlove may reduce fatigue in hand muscles. According to GM, research shows fatigue can affect the worker after just a few minutes gripping the same tool. According to Kurt Wiese, vice president of GM Global Manufacturing Engineering, “The successor to RoboGlove can reduce the amount of force that a worker needs to exert when operating a tool for an extended time or with repetitive motions.”

             A single modular battery unit can be worn on a worker’s belt and power two Robogloves for an 8-hour shift.  Inside the glove are mechanical actuators that pull on synthetic tendons that run across the palm up into the fingers of the glove.  A microcontroller is on the side of the glove and there are a set of sensors at the fingertips and base at the microcontroller.  These communicate to the glove when to grip, by how much and when to open back up. 

Licensing the Technology 

           NASA technology can be licensed by your business

         GM has licensed the glove to Swedish biomedical firm Bioservo Technologies AB for refinement and “to address other issues,” as well as to include Bioservo’s SEM (soft extra muscle) technology in a production glove.

                 RoboGlove can grip harder, but it cannot lift a heavy tool off a table and then hold it in place against the work piece. Tomas Ward, CEO of Bioservo Technologies, said RoboGlove is an important step toward producing a force amplifying exoskeleton for humans. Other automakers and tech companies are researching exoskeletons as force amplifiers, including BMW, Hyundai, and Panasonic. A human with extraordinary strength from the exoskeleton might be more flexible than a fork lift truck or robot — not to mention make auto factory tours more exciting.

Other applications for RoboGlove

          GM, NASA, and Bioservo all say RoboGlove has important medical applications. During rehab, a patient might quickly gain the gripping force he or she had before the illness. For someone forced to live with limited hand dexterity, RoboGlove could give the person the power he had 25 years ago to open a jar of jam — if only he can remember, once he’s back from donning the glove, what jar it was he wanted to open.


                  Harvard Biodesign Lab
         Augmenting and restoring human performance

           Next generation soft wearable robots that use innovative textiles to provide a more conformal, unobtrusive and compliant means to interface to the human body. These robots will augment the capabilities of healthy individuals (e.g. improved walking efficiency) in addition to assisting those with muscle weakness or patients who suffer from physical or neurological disorders. 
As compared to a traditional exoskeleton, these systems have several advantages:
    1. the wearer's joints are unconstrained by external rigid structures, 
    2. and the worn part of the suit is extremely light.  These properties minimize the suit's unintentional interference with the body's natural biomechanics and allow for more synergistic interaction with the wearer.

Structured functional textiles

          Exosuits attach to the body securely and comfortably, and transmit forces over the body through beneficial paths such that biologically-appropriate moments are created at the joints.   In addition, these garments can be designed to passively (with no active power) generate assistive forces due to the natural movement of the wear for particular tasks. A key feature of exosuits is that if the actuated segments are extended, the suit length can increase so that the entire suit is slack, at which point wearing an exosuit feels like wearing a pair of pants and does not restrict the wearer whatsoever.

Lightweight and efficient actuation

          In order to provide active assistance through the soft interface, a number of actuation platforms that can apply controlled forces to the wearer by attaching at anchoring points in the wearable garment. Lightweight and fully portable systems and a key feature  minimized distal mass that is attached to the wearer through more proximally mounted actuation systems and flexible transmissions that transmit power to the joints.

Wearable sensors

        New sensor systems that are easy to integrate with textiles and soft components are required in order to properly control and evaluate soft exosuits. Rigid exoskeletons usually include sensors such as encoders or potentiometers in robotic joints that accurately track joint angles, but these technologies are not compatible with soft structures.  New approach is to design new sensors to measure human kinematics and suit-human interaction forces that are robust, compliant, cost effective, and offer easy integration into wearable garments.               
            In addition, other off the shelf sensor technologies (e.g. gyro, pressure sensor, IMU) that can be used to detect key events in the gait cycle. These wearable sensors are used as part of the control strategy for the wearable robot or alternatively to monitor and record the movement of the wearer (when wearing the exosuit or as a standalone sensor suit) for tracking changes over time or determining what activities they are performing (e.g. walking vs running).

3. Other Materials 

         Knitting and weaving artificial muscles could help create soft exoskeletons that people with disabilities could wear under their clothes to help them walk, according to new research.

         The team started with cellulose yarn, which is biocompatible and renewable, and knitted and weaved it into a variety of textiles. These textiles were then coated with a conducting polymer called polypyrrole (PPy) using a process similar to how commercial fabrics are dyed.

         PPy has been widely used to create soft actuators because it changes its size when a low voltage is applied to it, thanks to ions and solvents moving in and out of the polymer matrix. As this material coats the fiber, it contracts when a positive voltage is applied and expands when a negative voltage is applied.

        The researchers found that weaving the fabric resulted in a textuator that produced high force, while knitting resulted in less force but an extremely stretchy material.

         By varying the processing method and the weaving or knitting pattern, Jager told Live Science it should be possible to tailor the force and strain characteristics of a textuator to the specific application at hand. To demonstrate the capabilities of the approach, the scientists integrated a knitted fabric into a Lego lever arm and it was able to lift 0.07 ounces (2 grams) of weight.

         At present, the material still needs to be submerged in a liquid electrolyte, which serves as a source of ions for the PPy. The material also responds much more slowly than mammalian muscle, taking minutes to fully expand or contract.

           Jager said his group is already designing a second generation of textuators that will address these issues. Decreasing response time is simply a matter of reducing the diameter of the yarn to a few micrometers he said, which commercially available textile-processing machines are capable of doing. The researchers are also working on ways to embed the electrolyte in the fabric so that it can operate in air.

July 14, 2017

Soyuz FG U15000-065 Manned flight rocket

            This rooket called "Soyuz FG" is used, for  launch both cargo or manned, by Russian space program and also for international collaboration project .
             It is a rocket that has been in operation since 2001 and is used for the launch of goods, astronauts and satellite launches to the International Space Station. 
   Launching from the launch pad visible in the photo 

           A small rocket attached to the tip of the rocket visible in the photograph is a "launch escape system (LES)", and if something goes wrong with the rocket during launch, for each Soyuz spacecraft aboard the astronaut It is pulled and carried to a safe place. 

     Soyuz FG is a 2-3 step type rocket, with four auxiliary rockets on the first row as if surrounding the main body as shown in the picture. 

           Although it looks like there are a lot of engines, in reality there is only one in each (one in the main body of the first stage, one in the auxiliary rocket). This is because one nozzle is not one nozzle, but four nozzles. The small nozzle on the side of it controls the attitude of the rocket.

               The launch capability of Soyuz FG can launch a mass of 7800 kg in orbit as if the International Space Station is orbiting.  Arrival at the International Space Station is about 6 hours after launch. It seems long, but until 2013 it took two days from launch to arrival.