What is the big failure that occurred just before the launch of the Mars probe 'Spirit' and the lessons learned from it?
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The Mars rover `` Spirit '' was launched in June 2003 and operated from January 2004 to May 2011, and together with `` Opportunity '' conducted various investigations on Mars. However, Chris Lewicki of NASA, who was in charge of Spirit's development, looks back on the big problem that occurred on the day when Spirit's launch was approaching two weeks ago.
My $500M Mars Rover Mistake: A Failure Story — Chris Lewicki
https://www.chrislewicki.com/articles/failurestory
Spirit was equipped with 62 brushed motors to drive its wheels, change direction, and control its robotic arm, camera, and antenna. In order to carry out the mission on Mars, which is a harsh environment, Spirit underwent various tests, and Lewicki was in charge of testing the motor of the rock abrasion tool (RAT) attached to the tip of the robot arm. Did.
During the test, which took place on a February day in 2003, the spacecraft was operated for an extended period of time to confirm that its various functions functioned without any problems. Lewicki and his colleagues used a device called a 'breakout box' to physically separate the motor from the spirit and connect it to an external power source and recording device. “With a breakout box, the current graph decreases exponentially when the motor is working properly, and various signals are emitted when there is a problem.
In order to get a proper signal from the motor, it is important to give it just the right amount of power, and if you connect it incorrectly, it can cause catastrophic damage to the entire system.
When Mr. Lewicki and his colleagues started testing, they noticed that the graph, which normally shows a downward-sloping line, was showing abnormal values. Lewicki and his colleagues immediately began investigating and discovered that power had been mistakenly sent to the entire spacecraft instead of to the motors.
When Mr. Lewicki reported the current situation to his colleague Leo, who was conducting other tests regarding Spirit, Mr. Leo replied, ``Indeed, all signals from Spirit were lost earlier.'' Mr. Leo said. When Mr. Lewicki's boss, Mr. John, heard all of this, he immediately halted the Spirit and instructed Mr. Lewicki and others to conduct a briefing regarding the damage.
Mr. Lewicki, who was worried that he would be fired over this incident, was told by Matt, the assembly test and launch operations manager, to ``jot down everything you remember about what happened.'' Based on this memo, the development team investigated the current state of Spirit.
The investigation was based on two points: ``A large electrical pulse flowed to an unintended location other than the motor,'' and ``All signals from the spacecraft were lost.'' As a result, it was found that the current was flowing into the H-Bridge motor driver. It turned out that the excess energy was flowing into a circuit called a 'circuit' that can properly process the excess energy. It was also revealed that the system temporarily went down as a result of high current flow.
So the development team performed the normal power-on procedure and restarted the Spirit. The various electronic devices on board were supposed to come online, start the software, and send a signal, but no matter how long we waited, the signal was never sent to the development team.
In despair, Mr. Lewicki conducted a detailed investigation into why the signal was not being transmitted, saying, ``My name will be written on a page of the history of failure in space exploration.'' As a result, it turns out that the multimeter monitoring Spirit's voltage has been removed and is being used to test the motor. Mr. Lewicki initially thought that this multimeter was not being used in this Spirit test and removed it, but in reality, this multimeter was incorporated into the circuit that receives the signal from Spirit. It became clear that there was. In other words, Mr. Lewicki inadvertently removed the multimeter, which led to this signal interruption.
After that, I returned the multimeter to its original location and tested it, and as a result, I successfully received the signal from Spirit. Mr. Lewicki, who also successfully launched Spirit in June 2003, said, ``Let's use this failure to our advantage next time.Failure is a valuable learning opportunity, and it strengthens our abilities and ability to bounce back from failure.'' It enhances the
Mr. Lewicki later became flight director for Spirit and Opportunity, which explored the surface of Mars, and received NASA's Lifetime Achievement Award. Mr. Lewicki reflects, ``This failure not only helped me grow, but also gave me the strength to overcome challenges.''
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