Engineering topics
Publications and source records attributed to Tsuyuki, Glenn.
The presentation describes a Smart Thermal Block Diagram Tool. It is used by JPL's Team X in studying missions during the Pre-Phase A. It helps generate cost and mass estimates using proprietary data bases.
An adequate warm-up heater approach was developed using analysis & previous Mars surface experience. In the worst-cold environment, all the actuators were able to warm to their minimum operating temperature within the required time. In the worst-hot environment, the maximum continuous actuator power dissipation during normal operations was determined. A mechanical thermostat provides best means to cope with a failed-on wrist heater & to ease RA operations planning.
In January 2004, two Mars Exploration Rovers (MER) landed on the surface of Mars to begin their mission as robotic geologists. A year prior to these historic landings, both rovers and the spacecraft that delivered them to Mars, were completing a series of environmental tests in facilities at the Jet Propulsion Laboratory. This paper describes the test program undertaken to validate the thermal design and verify the workmanship integrity of both rovers and the spacecraft. The spacecraft, which contained the rover within the aeroshell, were tested in a 7.5 m diameter thermal vacuum chamber. Thermal balance was performed for the near earth (hot case) condition and for the near Mars (cold case) condition. A solar simulator was used to provide the solar boundary condition on the solar array. IR lamps were used to simulate the solar heat load on the aeroshell for the off-sun attitudes experienced by the spacecraft during its cruise to Mars. Each rover was tested separately in a 3.0 m diameter thermal vacuum chamber over conditions simulating the warmest and coldest expected Mars diurnal temperature cycles. The environmental tests were conducted in a quiescent nitrogen atmosphere at a pressure of 8 to 10 Torr. In addition to thermal balance testing, the science instruments on board the rovers were tested successfully in the extreme environmental conditions anticipated for the mission. A solar simulator was not used in these tests.
This paper will describe the various design modifications made on the MER HRS from that of Mars Pathfinder spacecraft. A description of the flight performance during the seven-month cruise of the spacecraft will be given. A comparison of the performance on the ground and the flight will be presented. Any significant deviation in the flight performance will be described.
Contents include the following: Mission Overview. Thermal Environments. Driving Thermal Requirements. Thermal Design Approach. Thermal Control Block Diagram. Thermal Design Description. Thermal Analysis Results Summary. Testing Plans. Issues & Concerns.
This slide presentation reviews the thermal design for the Mars exploration rover project. It includes information on the spacecraft configuration, the cruise scenario, landing scenario, instrument package, thermal environment, and spacecraft schematics.