Impact Switch Study Modeling & Implications

Transcription

1 L-3 Fuzing & Ordnance Sysems Impac Swich Sudy Mdeling & Implicains Dr. Dave Frankman May 13, 010 NDIA 54 h Annual Fuze Cnference This presenain cnsiss f L-3 Crprain general capabiliies infrmain ha des n cnain cnrlled echnical daa as defined wihin he Inernainal Traffic in Arms ITAR Par r Epr Adminisrain Regulains EAR Par

2 Agenda Sudy mivain Inrducin spring/mass impac swiches Derivain f spring/mass gverning equains frm firs principles Resuls f sudy Derivain f mass/spring/damper sysem Resuls f parameric damping sudy Cnclus 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr

3 Mivain Dynamic/saic behavir revealed Swich clsure is dependen n he ampliude and durain f shck Evaluae curren eg pracices Enable characerizain f swich behavir analyically raher han empirically 5/19/010 3 The infrmain in his presenain is f general capabiliies and pen fr

4 Impac Swiches are Spring/Mass Sysems Accelerain Mass clses swich upn cnac Accelerain The infrmain in his presenain is f general capabiliies and pen fr 5/19/010 4

5 Spring/Mass Min Derived frm Firs Principles The gverning inhmgeneus Ordinary Differenial Equain ODE is derived frm Newn s secnd law ΣFma The spring mass sysem has a naural frequency f k/m A half e accelerain pulse is applied he swich F m k m a a /19/010 The infrmain in his presenain is f general capabiliies and pen fr 5

6 ODE Slved via. Mehd f Undeermined Cef s 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 6 A A A h A p Equain gverning psiin f mass Hmgeneus and paricular sluin are cmbined frm sluin yy p y h

7 Swich Clsure Befre Pulse Ends Swich clses befre accelerain pulse ends </ Mass mves a spring/mass naural frequency 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 7

8 Swich Clsure Afer Pulse Ends Swich clses afer accelerain pulse ends >/ Mass has sufficien kineic energy clse he swich afer he accelerain pulse ends. This scenari requires he sluin f anher ODE. 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 8

9 Min f Mass Afer Pulse Requires Anher ODE Sluin Sluin he hmgenus ODE is cmpleed ug he mehd f undeermined cefficiens. 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 9 A i i V m k 0 [ ] [ ] V i i cs

10 Swich Clses a Varius Accelerain Levels Lnger durain pulses apprach seady sae Appr half he seady sae accelerain 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 10

11 Unusual Behavir f Spring/Mass is Eplained If he mass has zer ne displacemen and a res a he end f he pulse, he sluin appraches he seady sae sluin 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 11

12 Damping Was Als Sudied Damping rai was paramerically sudied 0 ζ<1 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 1 km c Where A c m a k m F ζ ζ e e e A d d d d d d d ζ ζ ζ ζ ζ ζ cs cs

13 Damping Miigaes Oscillains 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 13

14 Damping Suppresses he Spring/Mass Oscillains 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 14

15 Cnclus Impac swiches will clse a a variey f differen accelerain levels Clsure f he impac swich becmes independen f durain as he pulse is lenghened Damping increases he accelerain level required clse he swich Damping miigaes he swich naural frequency Predicing he behavir f he impac swich enables L-3 FOS reduce develpmen ime 5/19/010 The infrmain in his presenain is f general capabiliies and pen fr 15