Mini-Payload Integration Center (Mini-PIC). This system is a fairly portable ground-based hardware system that emulates the proposed configuration and capabilities of the BTF rack. It has been developed to enable principal investigators to develop protocols and carry out duplicate control experiments in their own labs.
All dates offered below are approximate and are based on the schedule provided to the Task Group by NASA in the summer of 1999.
Phase I (2000 through mid-2003). Biotechnology research on the ISS occurs using instruments that already exist and were used or planned for use on the space shuttle. These instruments will be installed in EXPRESS racks in whatever laboratory modules have been completed. These preexisting pieces of hardware were not designed for long-term flight and often do not fulfill ISS requirements for configuration and resource use, but they will receive waivers to allow continuation of the science program while new hardware is developed and constructed. The performance of hardware during this phase will provide valuable input to the design and development of ISS-specific equipment. Another constraint on scientific work done at this time will be the ongoing construction of the ISS, which will limit both the time crew can be involved in research and the available transport volume on the shuttle. At this point, ISS resources, such as power, will also be limited and may not be reliable.
Phase II (mid-2003 through 2005). The boundary between Phase I and II is not a distinct one. Instead, there will be a gradual transition in the type of biotechnology instrumentation flown on the ISS. Phase II instrumentation consists of modular units that have been designed specifically to be used for long-duration (several months or more) experiments on the ISS. These instruments can be expected to have fewer performance risks and to meet ISS hardware requirements. Also, new efficiencies and capabilities should have been added to the equipment. For example, exchanging various sample units within hardware was not vital on a 2-week shuttle mission but would be necessary to maximize the science return from a long-duration flight. Another difference between Phase I and Phase II is that although the ISS will still be under construction, the availability of launch volume and on-orbit resources should increase. Equipment would still be housed in EXPRESS racks, but at that point both the U.S.-provided laboratory module and the Japanese-provided module should be operating.
Phase III (2005 and beyond). The transition to Phase III is sharply defined by the installation of the specialized BTF on ISS. This facility will still accept modular hardware of the type used in Phase II, but the facility will provide additional support capabilities designed specifically to enable biotechnology work on ISS. Current plans call for the BTF to provide each experimental module within it with power, gases (such as nitrogen and carbon dioxide), thermal cooling, data acquisition, storage and processing, video and image analysis, data downlink, real-time control, resource allocation, research-grade water, and vacuum exhaust for one modular unit at a time. Also, BTF will have an intelligent power distribution system to allow for efficient management of this scarce resource and to ensure that cuts in power are consistent with the constraints of each payload (i.e., power will be cut first to those payloads that are able to recover from the power outage without a sustained loss in performance). As well as using all of BTF, biotechnology experiments will also continue to operate in EXPRESS racks on ISS, when volume is available.