Flexure based mechanism with reduced stiffness

Flexure based mechanism (1), comprising:- a first body (3) supported on a second body (5) by a guide arrangement (7) comprising at least one flexure arranged so as to permit said main body (3) to displace relatively to said second body (5) from a neutral position according to at least one degree of freedom and subject to a restoring force acting in said at least one degree of freedom and directed towards said neutral position, one of said first body (3) and said second body (5) being a fixed support;- at least one preloaded buckled beam (9) arranged to apply a compensating force to said first body (3), said compensating force having a component acting in said at least one degree of freedom in a positive proportional relationship to a displacement of said first body (3) from said neutral position.according to the invention, said at least one preloaded buckled beam (9) is attached to a preloading structure (10) comprising a preloading body (11) supported by at least two preloading beams (13) preloaded so as to apply said compensating force, said at least two preloading beams (13) extending from opposite sides of said preloading body (11) in a chevron configuration, said chevron configuration defining an apex directed towards said at least one preloaded buckled beam (9).