The evolution of feeding mechanisms in the ray-finned fishes (Actinopterygii) is a compelling example of transformation in a musculoskeletal complex involving multiple skeletal elements and numerous muscles that power skull motion. Biomechanical models of jaw force and skull kinetics aid our understanding of these complex systems and enable broad comparison of feeding mechanics across taxa. Mec...

In this paper, a novel unsymmetrical five–four bar Planar Parallel Manipulator (PPM) with three Degree-of-Freedoms (DOFs) is proposed, the new manipulator is composed of a double-layer five-bar part with a four-bar part located in between. Targeting for the application of Chinese dish cooking machine, the detailed kinematics analysis for the new PPM is developed. Different from traditional thre...

A hybrid knee prosthesis is proposed in this letter, which consists of a polycentric structure passive mode for low-torque activities and single-axis active high-torque activities. novel transition mechanism controls self-holding electromagnets switching modes between the four-bar linkage structure. Compared with conventional knee, varying instantaneous center rotation (ICR) can enhance geometr...

Modulation-transfer-function (MTF) measurement often involves the use of three- and four-bar resolution targets. In the conversion of three- and four-bar image data to MTF, biased results can occur when we use series-expansion techniques appropriate for square-wave targets of infinite extent. For systems where the image data are digitally recorded, a convenient and accurate conversion of bar-ta...

This paper presents design modification to the existing standard wheelchair by incorporating an improved propulsion system and also braking and tilting systems that allow its full control with only one hand. The proposed design has the propulsion system with a chain drive powered through a four-bar linkage driven by the main handle. The desired direction of motion is obtained by moving the leve...

The ankle is a highly congruent joint with a surface area of 11-13 cm(2). Total ankle replacements have been attempted since the early 1970s and design has continually evolved as the early designs were a failure. This was because the stresses involved and the mutiaxial motion of the ankle has not been understood until recently. It has been shown that the talus slides as well as rolls during the...

A practical architecture, using a four-bar-linkage, is considered for the University of Minnesota direct drive rotot1. This statically-balanced direct drive robot has been constructed for stability analysis of the robot in constrained maneuvers.2-6 As a result of the elimination of the gravity forces (without any counter weights), smaller actuators and consequently smaller amplifiers were chose...

Force feedback control is investigated for improving the quality of the haptic feedback in virtual reality applications. Advanced control design can increase the transparency of the haptic device at the haptic interface thereby increasing the realism of the simulation. Force feedback also enables the implementation of admittance control approaches heretofore considered the domain of large robot...

A practical architecture, using a four-bar-linkage, is cgnsidered for the University of Minnesota direct drive robot [8]. This staticallybalanced direct drive robot has been constructed for stability analysis of the robot in constrained manipulation [5 -7]. As a result of the elimination of the gravity forces (without any counter weights), smaller actuators and consequently smaller amplifiers w...