Spherical mechanism constructed with scissors linkages with control means

Curved spherical scissors linkage mechanism (1) comprising at least four linkage elements (2) each having a first end (3) and a second end (4), the linkage elements (2) being arranged to form sides of at least one rhombus or of at least one parallelogram, wherein:

• the curved spherical scissors linkage mechanism (1) is extendable between a fully collapsed configuration and a fully extended configuration,
• each of the linkage elements (2):
• is rotationally connected to at least one of the other linkage elements (2) via a revolute joint (5)
• at or near the first end (3) and/or
• at an intermediate point (6) between the first end (3) and the second end (4), and
• is rotationally connected to at least another one of the other linkage elements (2) via another revolute joint (5)
• at or near the second end (4) and/or
• at an intermediate point (6) between the first end (3) and the second end (4), and
• the linkage elements (2) are shaped, dimensioned and arranged so that the axes of all said revolute joints (5) coincide at one common remote centre of motion (RCM), so that each of the linkage elements (2) can move on the surface of an imaginary sphere having its centre at the common centre of motion (RCM), and
• the curved spherical scissors linkage mechanism (1) is grounded or connected or connectable to a first external member (7) via the revolute joint (5) between linkage elements (2) arranged at a proximal end (8) of the curved spherical scissors linkage mechanism (1) and is rotationally connected or connectable to a second external member (9) via the revolute joint (5) between linkage elements (2) arranged at a distal end (10) of the curved spherical scissors linkage mechanism (1), the proximal and distal ends (8,10) being located at opposite ends of the spherical scissors linkage mechanism (1), and
• wherein the curved spherical scissors linkage mechanism further comprises:
• actuator means for activating the spherical scissors linkage mechanism (1), and
• either control means for controlling the actuator means or connectors in communication with external control means for controlling the actuator means,
• and/or energy storing means for storing elastic potential energy arranged and dimensioned to enable movement of the curved spherical scissors linkage mechanism by balancing gravity and, if the mechanism is used in an exoskeleton, body-power applied by a wearer of the exoskeleton
• wherein a motion controlling mechanism (15) is arranged at the proximal end (8) and/or at the distal end (10), and wherein for each motion controlling mechanism (15):
• the linkage elements (2) at the proximal end (8) or the distal end (10), respectively, are mutually connected at intermediate points (6) so that parts of these linkage elements (2) extend away from the curved spherical scissors linkage mechanism (1),
• the motion controlling mechanism (15) comprises these extending parts (16) of the linkage elements (2), and
• the movement of the curved spherical scissors linkage mechanism (1) can be controlled by moving the two extending parts (16) of the linkage elements (2).