Design and production of AMS-02 main data acquisition computer the “JMDC”
The Taiwan group together is responsible to build the AMS main data acquisition (DAQ) computer, JMDC. The existing space grade parts cannot meet the performance requirement of AMS-02. A solution of using commercial-off-the-shelf (COTS) parts was adopted. Each COTS part used in AMS-02 electronics was selected carefully by verifying its specification. Dedicated heavy-ion beam tests, held at GSI, Germany, were used to verify their performance under the radiation environment. A dedicated test board was built for each COTS part, including PowerPC 750 CPU.
JMDC consists of a single board computer (JSBC) with PowerPC 750 CPU, a 112 GB buffer board (JBU) with flash chips and various interface boards. There are four identical JMDCs in the AMS-02 detector to increase reliability. Each module of JMDC was carefully verified in each design stage (engineer model stage, qualification model stage and flight model stage). Various environmental tests were also performed to verify the performance of JMDC under the extreme space condition, including the thermal vacuum test. Figure 1 shows the flight modules of JMDC. A fully integrated four JMDC’s in the crate, J-crate, is shown in Figure 2. In order to qualify the reliability of JMDC operation in space, it went through a serial of environmental tests and thermal vacuum tests.
Manufacturing of AMS-02 electronics and mechanical components
The major fraction of AMS-02 electronics was produced at NCSIST with support from Academia Sinica and NCU. In order to ensure the production went smoothly, a procedure had been set for each step from the design file transfer to the environmental tests, which includes:
Incoming parts screening and storage.
PCB design documents and verification.
PCB design verification.
Module assembly procedure.
Environmental stress test procedure.
In total, there are more than 1000 AMS-02 electronics boards with their mechanical parts (front panel, stiffener and crate) produced in Taiwan (Figure 3). Figure 4 shows a part of AMS electronics produced in NCSIST, Taiwan.
AMS-02 Asia payload operation center (POCC) in Taiwan
There were two AMS-02 payload operation centers constructed in Taiwan to share the operation load of AMS experiment since 2012. The major center is at NCSIST and the backup center is at NCU. More than 40% of shift duty are covered by POCCs in Taiwan. Figure 5 shows the opening ceremony of AMS Asia POCC at NCSIST with the presence of the formal Taiwan President Ying-jeou Ma, the NASA associate administrator for the Human Exploration and Operations Mission Directorate William H. Gerstenmaier and Professor Samuel C.C. Ting on July 3rd, 2012. Figure 6 shows the formal Taiwan President Ying-jeou Ma and William H. Gerstenmaier, associate administrator for the Human Exploration and Operations Mission Directorate at NASA, visited the AMS-02 Asia payload operation center at NCSIST.