A constraint Jacobian based approach for static analysis of pantograph masts

Structure synthesis and statics analysis of a foldable stair

“…Statics analysis is one of the most important tasks in synthesizing a foldable structure. Nagaraj et al [31] investigated the kinematics and statics of a kind of pantograph mast. They addressed the constraints of the joints by the Lagrange multiplier method.…”

“…(31) indicates that the largest tensile forces of links B 1 C 2 and C 1 A 2 are proportional to the number of stairs. Considering the general height of one floor is about 3 m and the height of one stair is 0.2 m, the number of stairs needed is 15 and the weight of one person is 100 kg and the disturbing force F=0.2G, so the inner forces of links B 1 C 2 and C 1 A 2 are 15 × 100 × 9:8 × ffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffiffi ffi 1 + 0:2 2 p = 14991 N and − 14× 100 ×9.8 ×(1+ 0.2)= −16464N, individually.…”

Development of a Novel Double-Ring Deployable Mesh Antenna

“…As shown in Figure 8, there are two different types of joints in the element: one is denoted as a 7-strut joint and the other is denoted as a 4-strut joint. Based on the result of DOF evaluation analysis [12,13], the DOF number of the deployable truss is 3. Besides the activator struts shown in Figure 6, two active cables can be added in the diagonal members of the outer and inner ring truss element.…”

Static and Kinematic Behaviour of a Foldable Truss Roof Structure

“…Langbecker [13] formulated the foldability equation using a purely geometric approach, which then was used to analyze the kinematics and determine the foldability/deployability of translational, cylindrical, and spherical configurations. The kinematic of pantograph structures has also been studied by obtaining the null space of a constraint Jacobian matrix or the Screw theory [14,15]. A scissor-hinged system consisting of several interconnected parallel linear SLEs was suggested as the supporting structure for membrane structures [16].…”