Electronic packaging for extended Mars surface missions

Extended Mars missions will require vehicles to survive a large number of extended temperature cycles. To address this issue for electronics, previous strategies have placed electronics in a "warm electronics box" where thermal management is more easily maintained. However, that strategy limits number and location of electronics. An alternative strategy allows electronics to be remotely located on actuator and wheel arms with no heating, which has the advantage of distributed control. This strategy requires the electronics to survive the Martian extremes of -120 to +20degreesC for the duration of the mission. In addition, wheel motor controllers may be mounted directly on the motor casing extending the temperature range on the warm side to +85degreesC (including some margin). Since missions may last 18 months or more and with day-night cycles on Mars at about 26 hours this will mean exposure to approximately 500 cycles. Typical testing is performed to 3x the number of cycles giving the electronics a testing requirement of 120 to +85degreesC for 1,500 cycles.