回复：回复：有一题大家可以试试

to finalize the final answer. the last step to optimize the solution is to optimize the step 1 and two. you need to find another point D' on the left of point D.


1- you need to reach the point D', trun left (and follow a straight tangentline to reach the cycle (R=10 from center)
2-then follow the cycle for 180+ degrees.
4-the last 90 degree (same as step 4 in my last post) straight line.

SO i think this makes the solution to be
finding the D' will take sometime but should not be a problem for most of you.