A fully 3-D printed, soft, monolithic 4-DoF fingertip haptic technology is provided, called FingerPrint, that stimulates linear and rotational shear, pressure, and vibration on the fingerpad. Constructed using an origami waterbomb base mechanism and printed from a flexible material, the device embeds four sets of eight foldable vacuum-powered pneumatic actuators to achieve three translational (x, y, z) and one rotational (torsion) tactile motions and forces of a tactor end-effector on the fingerpad skin.

A fully 3-D printed, soft, monolithic 4-DoF fingertip haptic technology is provided, called FingerPrint, that stimulates linear and rotational shear, pressure, and vibration on the fingerpad. Constructed using an origami waterbomb base mechanism and printed from a flexible material, the device embeds four sets of eight foldable vacuum-powered pneumatic actuators to achieve three translational (x, y, z) and one rotational (torsion) tactile motions and forces of a tactor end-effector on the fingerpad skin.

A vibratory compactor is provided. The vibratory compactor may include a compactor plate, a frame coupled to the compactor plate, wherein the frame may include an inner space and a housing. The frame may include a plurality of mounting brackets coupled between a first side member and a second side member of the frame. The vibratory compactor may include a vibration generation device coupled to the compactor plate within the inner space of the frame. The vibratory compactor may include a plurality of isolators, each isolator coupled to one mounting bracket of the plurality of mounting brackets. The housing may be coupled to the plurality of isolators, wherein the housing may include couplers removably coupled to a top surface of the housing. The couplers may be configured for coupling the vibratory compactor to an excavator type vehicle.

A vibratory compactor is provided. The vibratory compactor may include a compactor plate, a frame coupled to the compactor plate, wherein the frame may include an inner space and a housing. The frame may include a plurality of mounting brackets coupled between a first side member and a second side member of the frame. The vibratory compactor may include a vibration generation device coupled to the compactor plate within the inner space of the frame. The vibratory compactor may include a plurality of isolators, each isolator coupled to one mounting bracket of the plurality of mounting brackets. The housing may be coupled to the plurality of isolators, wherein the housing may include couplers removably coupled to a top surface of the housing. The couplers may be configured for coupling the vibratory compactor to an excavator type vehicle.

For tamping a track, tamping tines are squeezed towards one another in pairs by a squeezing cylinder. A vibration is superimposed on a linear lift motion of a squeezing piston movable in the squeezing cylinder. The vibration is generated by a vibration piston which is arranged in the squeezing cylinder and which is movable independently of the squeezing piston.

For tamping a track, tamping tines are squeezed towards one another in pairs by a squeezing cylinder. A vibration is superimposed on a linear lift motion of a squeezing piston movable in the squeezing cylinder. The vibration is generated by a vibration piston which is arranged in the squeezing cylinder and which is movable independently of the squeezing piston.

An elastic material vibration test apparatus includes a lower support plate having an upper surface on which an elastic material to be tested is placed, an upper support plate disposed above the lower support plate to be spaced apart from the lower support plate, a pillar connecting the lower support plate and the upper support plate, a pressing rod configured to pass through the upper support plate and ascend and descend in a vertical direction, an air bearing installed on the upper support plate and supporting an outer surface of the pressing rod in a non-contact state, a pressing plate coupled to a lower end of the pressing rod to press an upper surface of the elastic material, and one or more weights coupled to the pressing rod above the air bearing.

A vibratory compactor is provided. The vibratory compactor may include at least one load bearing member coupled to a load bearing base and a frame coupled to a compactor plate with the load bearing base coupled to the frame. The frame and compactor plate are configured to vibrate. The vibratory compactor may also include a housing having an inner volume, the housing coupled to the frame by at least one isolator with the frame and the at least one load bearing member located within the inner volume. The housing may be coupled to an arm of an excavator. In response to force being applied to the housing by the excavator during compaction, the housing moves with respect to the frame until a top member of the housing contacts the at least one load bearing member and compacts soil more effectively than a vibratory compactor without the load bearing member.

An elastic material vibration test apparatus includes a lower support plate having an upper surface on which an elastic material to be tested is placed, an upper support plate disposed above the lower support plate to be spaced apart from the lower support plate, a pillar connecting the lower support plate and the upper support plate, a pressing rod configured to pass through the upper support plate and ascend and descend in a vertical direction, an air bearing installed on the upper support plate and supporting an outer surface of the pressing rod in a non-contact state, a pressing plate coupled to a lower end of the pressing rod to press an upper surface of the elastic material, and one or more weights coupled to the pressing rod above the air bearing.

A system includes a first structure, wherein the first structure lacks space inversion symmetry, and wherein the first structure includes a first elastic lattice. The system further includes a second structure, wherein the second structure lacks space inversion symmetry, and wherein the second structure includes a second elastic lattice. Additionally, the system includes the first structure coupled to the second structure such that the first structure and the second structure have a mirror symmetry to each other.