1. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] WPT-S MEFISTO-S [WPT: Team members] Lead Co-IY. Kasaba (JAXA) ManufacturerNIPPI [PWI] K. Ishisaka, T. Okada (Toyama Pref. U.) A. Matsuoka, T. Abe (JAXA) L. Blomberg (KTH [MEFISTO]) M. Moncuquet (LESIA [SORBET]) [System] K. Komatsu, Y. Morita (JAXA) With the aide of PWI team members & MMO system members [WPT: Team members] Lead Co-IY. Kasaba (JAXA) ManufacturerNIPPI [PWI] K. Ishisaka, T. Okada (Toyama Pref. U.) A. Matsuoka, T. Abe (JAXA) L. Blomberg (KTH [MEFISTO]) M. Moncuquet (LESIA [SORBET]) [System] K. Komatsu, Y. Morita (JAXA) With the aide of PWI team members & MMO system members WPT-S15m x 2 MEFISTO15m x 2 PWI/WPT (Wire Probe anTenna)

2. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] PWI/WPT (Wire Probe anTenna) Mechanical – past Design *Vertical *Latch release: wire cutter with Pyro *After the release: Stopped by the tension between “wire” & “spring in Holder” *Plane-gear mechanism

3. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] (1) Progress from the last design meeting (Sep. 2005) >> * Overall Design: 3 changes - “Horizontal”: reduce the sun-lit part - Latch: released by “motor, without Pyro” - Addition of “spacer” * Mass reduction study: failed O Plane-gear 600g at this moment ? Worm-gear 630g (structure: -15g, gear ： -30g, motor: +75g ） A/I: - “Light-weight motor” – Torque requirement is Margine = x4 at Retraction in full-extension [Heritage of MAST design] - Reduction of the required torque: *reduction of torque margine? *reduction of spin rate at the full extension? [depending on initial centrifugal force & attitude stability of the spacecraft] *refine of the requested retraction

4. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] (1) Progress from the last design meeting (Sep. 2005) >> *Test of the Latch mechanism Static load test: OK for “<53G” A/I ： Dynamic load test (based on the issued tentative environment condition) *Wire: Thermal-shock test – No problem A/I ： Strength test @ high temperature Establishment of the contact to the sphere Def. of I/F & Installation to the spacectaft Load direction

5. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] (1) Progress from the last design meeting (Sep. 2005) >> *MTMIt is not updated after September 2005 A/I:Update of MTM> Definition of I/F to Side/Lower panels > Update of I-ICD & CDD >> *Harness/Connector: Trough-hole at the lower deck Connector & harness at the “top-panel” of WPT-S A/I ： Def. of “Stepping motor” (incl. torque margine, mass, EMC) >> *Surface sample: Photo-electron / 2 nd electron yield will be measured. A/I:next week – Photo-electron distribution Future – Amount of Photo-electron / 2 nd electron yield >> *Attitude analyses: Preliminary analyses is “OK”. A/I: incl. Despun & non-symmetric extension

6. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] (3) Development plan in 2006 Establishment of “key parts design” Finish of the Environment test of BBM & Materials Updating (& reduction) of Mass Update of MTM, Establishment of the wire strength in High-T Establishment (& reduction) of Monitor items [= establishment of MAST/WPT-E] Establishment of the Motor power production from 50V-bus [= establishment of MAST/WPT-E] Establishment of the control scheme at the extension [= establishment of basic design of software on MDP] (5) Major request to System / Other subsystems & payloads Definition of I/F Definition of safety requirement (torque margin, strength margin) Purging for MoS2??? Spin axis direction, Reduction of surface charging Appendix. Current Resources (without margin) *Assigned mass545g (without margin) *Current design600g

7. BepiColombo/MMO: PWI/WPT-S PWI Kanazawa Meeting [Mar 2006] “+-4mm move” might be expected.