US Patent 8430643 Volumetric fluidics pump method with translating shaft

A pump for moving a fluid through a fluidics system includes a surface and channel disposed along at least a portion of the surface. The pump also includes a driving mechanism having a rotatable shaft and a plurality of haptics operably coupled to the shaft. A closed portion is formed in the channel as the channel is compressed between the surface and at least one of the haptics, the closed portion having a thickness between the surface and the haptic. The pump additionally has a circular path and a shaft path. The surface has a radius of curvature in the vicinity of the closed portion that is greater than the sum of a radius of the circular path and the thickness of the closed portion.