2. Successful design of any such system is dependent 

 on the use of comprehensive nonlinear modeling of 

 the proposed system throughout the design phase to 

 determine expected performance over the entire 

 range of planned operating conditions. 



3. A boom-bobber system properly designed causes 

 essentially no fatigue of the lift cable compared to 

 most other systems and, thus, should receive careful 

 consideration for all applications where lift-line 

 fatigue life is a major concern. 



4. The pure pneumatic spring used in the existing 

 MCLS is less desirable than a hydraulic cylinder com- 

 bined with a series of oil-over-gas accumulators 

 because of the difficulty of achieving the desired 

 pneumatic spring rate characteristic. 



5. A boom-bobber system appears to offer significant 

 dynamic line-tension control for all single-cable lift 

 requirements where the effective spring constant of 

 the lift cable selected is relatively high (e.g., wire 

 rope, Kevlar rope, and short lengths of nylon and 

 other synthetic lines). 



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