January 3, 2006
ALMA Prototype
Antenna Evaluation OverviewEvaluation Overview
5
VertexRSI and AEC Prototype Antennas
50%/50%
~108
tonnes
Hexapod
(5 DOF)
CFRP structure, Ò+Ó configuration
264 panels, 8 rings,
machined Al, open-back, 8 adjusters (3 lateral/5 axial) per panel
Absolute
(BEI)
Integrated
on servo motor
Gear and
pinion
3-point support; bolt connection
with foundation
Cynlindrical Invar;
thermally stabilized steel
Al honeycomb with CFRP plating,
24 sectors, open back, covered with removable GFRP sunshades
Insulated
Steel
VertexRSI
35%/65%
Mass
Dist. (El/Az)
~80
tonnes
Total
Mass
3-axis
mechanism
Focus
Mechanism
CFRP structure, ÒxÓ configuration
Apex/Quadripod
120 panels, 5 rings, Al honeycomb
with replicated Ni skins. Rh coated, 5 adjusters per panel
Panels
Incremental
(Heidenhain)
Encoders
Hydraulic
disk
Brakes
Direct-drive
with linear motors
Drive
6-point support; flanged attachments
Base
CFRP; direct-connection
cabin to BUS
Receiver
Cabin
Solid CFRP plates, 16
sectors, closed-back sectors glued and bolted together
BUS
Steel/Steel/CFRP
Base/Yoke/Cabin
AEC
Property
