|
Microsuction Tape
Microsuction tape is a material for sticking objects to surfaces such as furniture, dashboards, walls, etc. One side is usually attached to the base surface by a classical adhesive. Objects are attached to the other side by pressing them against the tape. They stick to the tape due to small bubbles (cavities) on the surface of the tape. These contain air, which is squeezed out when the surface of an object is pressed against the surface of the tape. Due to sealing properties of the material, when the object is pulled off the surface, a vacuum is created in the cavities. Due to external air pressure, this creates a force that prevents the object from being removed from the surface, a mechanism similar to that of a suction cup. When a large enough surface area of the object is pressed onto the tape, considerable force is necessary in order to detach the object by pulling it off. The mechanism is similar to that of a suction cup, where a well attached cup with a radius of 2 cm ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suction Cup
A suction cup, also known as a sucker, is a device or object that uses the negative fluid pressure of air or water to adhere to nonporous surfaces, creating a partial vacuum. Suction cups are peripheral traits of some animals such as octopuses and squids, and have been reproduced artificially for numerous purposes. Theory The working face of the suction cup is made of elastic, flexible material and has a curved surface. When the center of the suction cup is pressed against a flat, non-porous surface, the volume of the space between the suction cup and the flat surface is reduced, which causes the air or water between the cup and the surface to be expelled past the rim of the circular cup. The cavity which develops between the cup and the flat surface has little to no air or water in it because most of the fluid has already been forced out of the inside of the cup, causing a lack of pressure. The pressure difference between the atmosphere on the outside of the cup and the low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Suction Cup
A suction cup, also known as a sucker, is a device or object that uses the negative fluid pressure of air or water to adhere to nonporous surfaces, creating a partial vacuum. Suction cups are peripheral traits of some animals such as octopuses and squids, and have been reproduced artificially for numerous purposes. Theory The working face of the suction cup is made of elastic, flexible material and has a curved surface. When the center of the suction cup is pressed against a flat, non-porous surface, the volume of the space between the suction cup and the flat surface is reduced, which causes the air or water between the cup and the surface to be expelled past the rim of the circular cup. The cavity which develops between the cup and the flat surface has little to no air or water in it because most of the fluid has already been forced out of the inside of the cup, causing a lack of pressure. The pressure difference between the atmosphere on the outside of the cup and the low ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Newton (unit)
The newton (symbol: N) is the unit of force in the International System of Units (SI). It is defined as 1 kg⋅m/s, the force which gives a mass of 1 kilogram an acceleration of 1 metre per second per second. It is named after Isaac Newton in recognition of his work on classical mechanics, specifically Newton's second law of motion. Definition A newton is defined as 1 kg⋅m/s (it is a derived unit which is defined in terms of the SI base units). One newton is therefore the force needed to accelerate one kilogram of mass at the rate of one metre per second squared in the direction of the applied force. The units "metre per second squared" can be understood as measuring a rate of change in velocity per unit of time, i.e. an increase in velocity by 1 metre per second every second. In 1946, Conférence Générale des Poids et Mesures (CGPM) Resolution 2 standardized the unit of force in the MKS system of units to be the amount needed to accelerate 1 kilogram of mass at the rate ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Friction
Friction is the force resisting the relative motion of solid surfaces, fluid layers, and material elements sliding against each other. There are several types of friction: *Dry friction is a force that opposes the relative lateral motion of two solid surfaces in contact. Dry friction is subdivided into ''static friction'' ("stiction") between non-moving surfaces, and ''kinetic friction'' between moving surfaces. With the exception of atomic or molecular friction, dry friction generally arises from the interaction of surface features, known as asperities (see Figure 1). *Fluid friction describes the friction between layers of a viscous fluid that are moving relative to each other. *Lubricated friction is a case of fluid friction where a lubricant fluid separates two solid surfaces. *Skin friction is a component of drag, the force resisting the motion of a fluid across the surface of a body. *Internal friction is the force resisting motion between the elements making up a so ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Sticky Pad
Sticky pads are friction devices used to prevent objects from sliding on a surface, by effectively increasing the friction between the object and the surface. Sticky pads are used to fix items to otherwise smooth surface that are leaned or that moves, so that objects put on that surface could off due to insufficient friction when the surface inclines or moves. The pad has large friction coefficient both with the base surface and with the item laid on it, which prevent both the sticky pad from moving with respect to the surface, and objects laid on the pad from moving relative to the pad. Sticky pads are commonly used on car dashboards where forces caused by acceleration of the vehicle would cause objects put on dashboards slip off the otherwise smooth surface of the dashboard. Contrary to fasteners, sticky pads do not affix objects to the surface. They merely prevent objects from slipping on the surface until the threshold acceleration or inclination angle is exceeded. Sticky pa ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gecko Tape
Nano tape, also called gecko tape; marketed under the name Alien Tape, is a synthetic adhesive tape consisting of arrays of carbon nanotubes transferred onto a backing material of flexible polymer tape. These arrays are called synthetic setae and mimic the nanostructures found on the toes of a gecko; this is an example of biomimicry. The adhesion is achieved not with chemical adhesives, but via van der Waals forces, which are weak electric forces generated between two atoms or molecules that are very close to each other. Explanation Geckos show a remarkable ability to climb smooth vertical surfaces at high speeds, exhibiting both strong attachment and easy rapid removal, or shear adhesion, of their feet. On a gecko's foot, micrometer-sized elastic hairs called setae are split into nanometer-sized structures called spatulas. The shear adhesion is achieved by forming and breaking van der Waals forces between these microscopic structures and the substrate. Nano tapes mimic th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Gecko Tape
Nano tape, also called gecko tape; marketed under the name Alien Tape, is a synthetic adhesive tape consisting of arrays of carbon nanotubes transferred onto a backing material of flexible polymer tape. These arrays are called synthetic setae and mimic the nanostructures found on the toes of a gecko; this is an example of biomimicry. The adhesion is achieved not with chemical adhesives, but via van der Waals forces, which are weak electric forces generated between two atoms or molecules that are very close to each other. Explanation Geckos show a remarkable ability to climb smooth vertical surfaces at high speeds, exhibiting both strong attachment and easy rapid removal, or shear adhesion, of their feet. On a gecko's foot, micrometer-sized elastic hairs called setae are split into nanometer-sized structures called spatulas. The shear adhesion is achieved by forming and breaking van der Waals forces between these microscopic structures and the substrate. Nano tapes mimic th ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Contact Mechanics
Contact mechanics is the study of the deformation of solids that touch each other at one or more points.Johnson, K. L, 1985, Contact mechanics, Cambridge University Press.Popov, Valentin L., 2010, ''Contact Mechanics and Friction. Physical Principles and Applications'', Springer-Verlag, 362 p., . A central distinction in contact mechanics is between stresses acting perpendicular to the contacting bodies' surfaces (known as normal stress) and frictional stresses acting tangentially between the surfaces (shear stress). Normal contact mechanics or frictionless contact mechanics focuses on normal stresses caused by applied normal forces and by the adhesion present on surfaces in close contact, even if they are clean and dry. ''Frictional contact mechanics'' emphasizes the effect of friction forces. Contact mechanics is part of mechanical engineering. The physical and mathematical formulation of the subject is built upon the mechanics of materials and continuum mechanics and fo ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
Vacuum
A vacuum is a space devoid of matter. The word is derived from the Latin adjective ''vacuus'' for "vacant" or "void". An approximation to such vacuum is a region with a gaseous pressure much less than atmospheric pressure. Physicists often discuss ideal test results that would occur in a ''perfect'' vacuum, which they sometimes simply call "vacuum" or free space, and use the term partial vacuum to refer to an actual imperfect vacuum as one might have in a laboratory or in space. In engineering and applied physics on the other hand, vacuum refers to any space in which the pressure is considerably lower than atmospheric pressure. The Latin term ''in vacuo'' is used to describe an object that is surrounded by a vacuum. The ''quality'' of a partial vacuum refers to how closely it approaches a perfect vacuum. Other things equal, lower gas pressure means higher-quality vacuum. For example, a typical vacuum cleaner produces enough suction to reduce air pressure by around 20%. But hig ... [...More Info...] [...Related Items...] OR: [Wikipedia] [Google] [Baidu] |
