ESP3

ESP-3 was detached from its Keel Yoke Assembly (which remained in the Orbiter) and installed on the P3 Truss at UCCAS-1 on August 14, 2007 during the Space Shuttle STS-118 mission. It has seven attachment sites for ISS spare parts and assemblies, called Orbital Replacement Units (ORUs). The platform also has handrails and attachment points for tethers and foot restraints that astronauts can use while working with the ORUs on the ESP-3. ESP-3, as with ESP-2 are deployable versions of the Integrated Cargo Carrier and have the same dimensions, approximately 8.5 feet long and 14 feet wide. ESP-3 has two grapple fixtures to aid deployment.

ESP-3 was the first major station element to be installed completely by robotics, using only the shuttle and station’s robotic arms, an external berthing camera system (BCS) and a Photovoltaic Radiator Grapple Fixture (PVRGF). Astronauts robotically installed the platform onto the station’s P3 truss segment during the STS-118 mission’s seventh day.

On January 12, 2010, the station’s robotic arm was used again to move ESP-3 from the P3 truss segment UCCAS-1 site. It was grappled by the arm and then transferred down the station’s backbone on the mobile transporter. ESP-3 was then attached to its new location on the lower part of S3 truss segment at the PAS-3 site. Moving the storage platform cleared the way for ExPRESS Logistics Carrier-3 to be installed during STS-134.

The ORUs (currently) installed on ESP-3 are:

• FRAM-1 (top side) Pitch/roll joint (P/R‐J) launched on ESP-3
• FRAM-2 (top side) Flex Hose Rotary Coupler (FHRC SN1004) added by STS-126 crew
• FRAM-3 (top side) empty
• FRAM-4 (top side) Linear Drive Unit (LDU) added by STS-127 crew
• FRAM-5 (keel side) Space-to-Ground Antenna (SGANT) added by STS-127 crew
• FRAM-6 (keel side) Battery Charge/Discharge Unit (BCDU) launched on ESP-3
• FRAM-7 (keel side) ATA Flight Support Equipment (FSE) added by STS-118 crew.