Performance of Pseudo-Elastic Flexure Hinges in Parallel Robots for Micro-Assembly Tasks

Size-adapted Parallel and Hybrid Parallel Robots for Sensor Guided Micro Assembly

“…Figure 8 shows an example of increasing stiffness and optimising the distribution of occurring forces by a suitable design of a combined flexure hinge. Torsional moments can better be absorbed and transformed into tension and compression forces, since the hinges are arranged in a parallel and angular pattern (Hesselbach et al, 2004a). Although the workspace is nearly triangular, a cube with a dimension of 112x112x112 mm³ would fit into the workspace with the present configuration.…”

“…Due to the large reversible strains of SMA, deflections of the hinges of ±30° are possible. This approach offers the potential to design robots with high accuracy and resolution and with a sufficiently large workspace for micro assembly tasks (Hesselbach et al, 2004a). SMA exists in austenite and martensite phases, depending on the temperature or the applied stress.…”

“…These geometrical dimensions are an optimum between small kinematic deviations compared to the kinematics of an ideal rotational joint and small occurring strains. The pseudo-elastic material can be modelled with a material model by Prandtl-Reuss if the deflection curve is calculated analytically (Howell & Midha, 1995), (Hesselbach & Raatz, 2000) or with a multilinear elastic material model using the FEM tool ANSYS. With the chosen geometry and geometrical dimensions maximal strains are ε=2.1% at deflections of 20° and ε=4.2% at 30°.…”

Development of a novel flexure-based microgripper for high precision micro-object manipulation

“…Its main characteristic to exploit the entire length of its slender profile for deformation has gained its primacy against other configurations. This attribute is paramount to produce optimum deflection while minimizing the stress concentration of the flexure hinge [24,25]. The circular geometry in contras allows deformation to localize only at its smallest cross section thus limits the amount of relative motion between adjacent links with high tendency to exhibit premature fatigue failure.…”

High Resolution Flexible 3-RRR Planar Parallel Micro-Stage in Near Singular Configuration for Resolution Improvement

“…Both mechanisms contain monolithic (composed of one unique part) kinematic chains made of flexible links. To get closer from what we want to work on, two studies written by Hesselbach et al [8] and Yi et al [9] concern planar parallel structures utilizing flexible links. The first one proposes a modeling of flexible notch hinge and then includes it into a planar parallel mechanism.…”