A conductor width change on the flex side of the flex-rigid transition could result in a stress concentration point, which in turn could cause the trace to crack when the circuit is flexed
. Discuss with your fabricator high-speed materials used in the rigid sections of the circuit.
This will provide the advantage of keeping plated copper off them (more on this topic to follow), and will also move them closer to the neutral bend axis to reduce stress when the circuit is flexed
When a flex circuit is bent or flexed
, there are stretching and compressing forces present in the bending area.
Skin, 1.5 x 0.5 inches, was fixed to the flexing device with double-sided tape and flexed
at 45[degrees], 20 flexes/minute, or left flat, for 15, 30, or 60 min.
Back Extensions: A staple in most programs, this is an excellent low-back exercise that starts with the body in the flexed
position (Photo 10) and then extended to a position in which the legs and torso are parallel to the floor (Photo 11).