This paper presents the design and modeling of an elastic inflatable actuator, EIA, to generate single and multiple motions through only one channel. The morphology proposed is focused on an external and internal design based on crests with amplitude and length defined. The EIA geometry change in magnitude and direction when pressure or vacuum is applied, generating the multiple motions expanding-contracting. Besides, by adding a thicker layer to a 180 ∘ or 120 ∘ section in the EIA, a bending motion is generated in the direction where the greatest thickness of the material is located. We describe a detailed design of the EIA and the modeling by FEM analysis for both single and multiple motions. In addition, we introduce a soft linear manipulator by using both single and multiple-motions EIAs, we design a soft gripper with 3 bending motion EIAs; the soft linear manipulator is composed of the multiple motions expanding-contracting EIA connected to the gripper. The manipulator needs only two controlled pressure inputs, the first one generates a linear displacement along its transverse axis and the second one controls the soft gripper closing-opening.