Abstract: A tracked skate runner provides a low-profile substitute for a wheel with exceptionally low rolling resistance on rough or soft terrain. The runner includes a skate frame and rollers that bear against an endless track of hinged links devoid of pinch points that can get jammed with ground debris. The skate frame provides a channel with sidewalls and a top dirt shield. The sidewalls fit closely with the links of the track to seal out dirt, and the top dirt shield protects the rollers from dirt that shakes off the top recirculating portion of the track.

Abstract: A tracked skate runner provides a low-profile substitute for a wheel with exceptionally low rolling resistance on rough or soft terrain. The runner includes a skate frame and rollers that bear against an endless track of hinged links devoid of pinch points that can get jammed with ground debris. The skate frame provides a channel with sidewalls and a top dirt shield. The sidewalls fit closely with the links of the track to seal out dirt, and the top dirt shield protects the rollers from dirt that shakes off the top recirculating portion of the track.

Abstract: Example energy-storage implementations are provided. One example implementation involves a device that has a gap extending between a first side of the device and a second side opposite to the first side. The first side is to overlap a first cell and a second cell. The device includes a first contact to couple with the first cell and a second contact to couple with the second cell. The device also includes a flexure having a curved edge adjacent to the gap. The curved edge extends from a first end positioned to overlap with the first cell to a second end positioned to overlap with the second cell. A curvature of the curved edge flexibly changes in response to a motion of the first contact.

Abstract: A push-paddle has a buoyant wedge-shaped push-block attached to the bottom end of a pole. When pressed into the water wedge-end first, the push-block provides high drag and buoyant force for the user to push against and propel a watercraft using a punting-like motion. At the end of the power stroke, the wedge slips easily and quickly up out of the water allowing the user to recoil the push-paddle through the air.

Abstract: A skateboard for use on pavement, ice or snow using a single narrow-footprint wheel, ice-blade or ski-runner attached to each foot, thus requiring the rider to dynamically balance the board. The skateboard is capable of self-propulsion at considerable speed on the flat or uphill by using an undulating motion. It can also lean up to 30 degrees and has a steering circle of only two feet. The board's construction comprises a front footboard, a rear footboard, and a strut which connects the two footboards and resists bending and extension. Each footboard includes a footpad, an attachment (i.e. a wheel, blade or ski), and a pivot joint connecting to the strut. The axis of this joint is aligned perpendicular to the footpad which allows the rider to steer each footboard independently by torsionally rotating the lower leg.

Abstract: A skateboard for use on pavement, ice or snow using a single narrow-footprint wheel, ice-blade or ski-runner attached to each foot, thus requiring the rider to dynamically balance the board. The skateboard is capable of self-propulsion at considerable speed on the flat or uphill by using an undulating motion. It can also lean up to 30 degrees and has a steering circle of only two feet. The board's construction comprises a front footboard, a rear footboard, and a strut which connects the two footboards and resists bending and extension. Each footboard includes a footpad, an attachment (i.e. a wheel, blade or ski), and a pivot joint connecting to the strut. The axis of this joint is aligned perpendicular to the footpad which allows the rider to steer each footboard independently by torsionally rotating the lower leg.