India's scripted history by soft landing near the south pole of the moon, a point which I now call Chandra Gago Tree Behind Me is a one is to one model of the Vikram Lander and the Pray Rover, and I have India's moon stars and Shrikant, the mission director if I can say Shiva, Shakti and Nara because the is the cosmic dance. And essentially, if Chandra and three was dancing around between Earth and the moon and then landing, it was through the hands of Sri Khan. That's why and to the team. One simple question and I'll hand over the mic one by one. To you, uh, you were involved with Chandra two and also with Chandra three New history. How did you convert those 20 minutes of terror into 20 minutes of joy? And how many hours a day did you work in these last almost four or five years? Or maybe longer from Chandra and to two, as you told it was a big success except for this power decent face where this 20 minutes we could not it did not go well, but we initially understood what was the problem, and we overcome that problem by identifying the root cause of the issue. And based on that, we have set up what needs to be corrected both in hardware and software. That was our first step in Chan. The second step is conceptualising and conducting the series of tests. Which what are the tests we could not do in Chandran two. That is called a field test like integrated coal test, where we carried all the sensors and navigation systems. We flew in the helicopter and conducted a series of tests to evaluate the sensors and navigations in Chitra, where we created artificial craters and boulders. The second test was integrated hot test where in all the sensors, absolute sensors, azar detection and avoidance sensors. Initial sensors. We are put in close loop with propulsion system, navigation, guidance and control. That was the second major test where we conducted dry run, static test and dynamic test. The third one was the Land Elect Mechanism Performance Test, where we conducted a series of tests again to evaluate Touchstone conditions like combination of horizontal and vertical velocities. Slow P surface flat terrain, hard surface, soft surface. We created a lunar soil simulant test bed, so these were the tests we conducted thoroughly in the beginning, we conceptualised and conducted the test over the time. How did you from ricotta to It was a precision route. There is no there is no GPS. How did you manage such a very critically closed landing as you had? And so this is very important because this time we we knew that, uh that the target point In fact, Chandra and two also, we had a similar target point this target point we have chosen in such a way that it is of scientific interest as well as we have to meet the engineering constraints also. So we built multiple mission parts this time. In fact, in Chad and two, we had two parts nominal and contingency part. This time we created multiple parts so that anything happens. We wanted a soft landing. That was our target. So we built a path like a real time re targeting in addition to nominal and contingency path. Sometimes if no alter update comes as you rightly told, there is no GPS in moon. So we have to have a relative terra rel navigation sensors for which we have altimeters. We have velocity sensors which will give position and velocity information and we have other detection and avoidance. At the end of it, we have to avoid the obstacles to have a soft landing. Did you sleep in these four years, or did you spend all your time in the satellite centre? See, To be honest, we are going to the second time. So not only me. The entire team was on our toes like right from the project. Approval till the launch stage, including the covid time was utilised by reviewing various systems like we have a strong review mechanism right from configuration stage, design stage and realisation stage at various stages. The reviews also plays a major role. So we utilised even the covid time for reviewing the systems. To be frank with you, that our entity as we were on toast to conduct this test and there were so many issues in the beginning while conducting the test and again we put a retrofit activities and finally finally, we have successfully completed the test for which one after other tests we have to do so. Continuous work was there till landing. Now you will be associate project director for Vikram Prag Chandra. What were the biggest challenges and how did you overcome them? Biggest challenge. What I would say is the scale of the project itself is very high. It's a mammoth project and there is a lot of multitasking involved and myself as associate project director, along with Project Director, we play a pivotal role in bridging all the teams together. The team is a very big team because, you know, like many Deputy project directors, project people were involved. It's like hundreds of people see, along with the project director, associate project director, we have around some 32 deputy project directors, hundreds of project managers and also many system engineers working along with them to support the project. So we have to handle this big team and also the tasks wise. It is a technical challenges which already he has detailed and also managerially. We have to ensure that all the activities are happening in sync. One side there is a flight. Hardware is coming up in the clean room. These special tests are happening at the fields and also a good amount of exhaustive simulations have to happen because everything can be done through tests. So very good amount of simulations have to happen. Like, you know, different platforms were developed. Six off oil cells, hardware simulator, different test test beds were developed. So all this should be happening in sync, and good interactions should be happening among the teams. So the data flow should be very good. Schedule is also equally important. So all these aspects multi task, multi tasking and working towards one common goal of completing soft landing. So we have to work as a team together and achieve all the objectives. So this was of multitasking. I cannot not bust but ask you. And that's a question to Vera. And she can't also. How did you manage work and home life? It is very complex. And in a long hour, when your smiling face was always there, I have seen Yes, definitely This calls for a lot of work life balance because the project is such so because we are working towards the goal. We want to finish the unfinished everyone. Every team members mindset is towards that. So what comes the priority if you ask. Work was first for the team and definitely work. Life balance was getting balanced. Family was a good support structure. Management was supporting us a lot in all aspects. So we had to balance between both And whenever work demanded, that was our priority. With a good amount of balance, we could manage this mission. But definitely work project was a priority. You embodied Nari Shakti for India and in Chandra and three Yes or no? You. I'm calling you and Shakti. We did what is required. You did what is required. See, that is the beauty in Israel, men and women work shoulder to shoulder only talent matters and one of the most talented people for mission objectives. We have Mr Shrikant, whom I call the because the N or the cosmic dance is what was really performed. The dance between Earth Moon Chandra three Vikram Prag. All of that was rightfully being controlled by Mr Shrihan. How difficult was the controlling the spacecraft as it was from ricotta all the way to Swati? Sir, when you say the satellite as single set has three elements, one is propulsion module. One is Lanta module Is Rover module all three in each. They are unique and have its own requirements and a combined requirements and contacting each other also. So all these things has to be balanced and the operations has to balance carried out pre planned prior before liftoff onwards after injection. The whole compost control has to be done by proper module and proper module has its own requirements by meeting the spacecraft objectives and at the same time, we need to do the lander calibration along with the proper module thing. And this phase, this phase of compass will continue in Earth bone phase as well as in moon bone phase. Then once lander gets separated, land has its own requirements. As Landers stand alone, it has to be operated for the mission object of landing the 20 minutes for that water major required sensors and our navigation related cameras and our near real time data download transmission chain. All these things needs to be tested in that six days alone. It is up there. So we have before the 20 minutes this was subjected for the actual usage. All these things were pre calibrated. Pre assessment was carried out in the six days. Then, during these 20 minutes, all of the systems have behaved, performed as per expectation have pinpointed landing and After landing, we had a rover which has to come out of the lander and do the mobility over the moon surface and Rover itself is a unique thing because till now we don't have any experience of lower mobility on any celestial body. So that operations itself is a unique thing. So we need to handle it in a in a semi autonomous way, near real time planning. So our whole teams which have worked for module, Land Rover, all of us together had only one object to that. Every objective for each phase is met full fledged And Rover has also made 100 metres in that 14 days, which is also one of the important milestones which we met. So all put together, all these three entities are challenging in each thing. So you are making and kuna the Shiva and Shakti dance to your requirements as you were conducting the orbital parameters between Earth and Moon and Chandra. Yes. See, actually, the point is when we need to do the orbit because we don't have any GPS. So we need to depend on our arbiter nation for the where the actual satellite is, so that for that our flight dynamics team, along with other navigation team from we had JPL navigation all put together. We have done where the satellite precisely in potion determination as well as the sensor used for actual control were calibrated. And we had, uh, good orientation control. Also, that is how we have made the satellite to dance as per the requirements from our side. So that was the dream team for all the moon stars of India, Shakti and Nara. As I call them. They don't call that but the team which made history for India by landing soft landing near the south pole of the moon. And we have a life size model of right here and Vikram right behind us. The same thing which Prime Minister Narendra Modi had a look at and the same size sits at the point in the lunar surface. India's celestial Moon dance with camera person Kumar inside the ISRO satellite facility in Bangalore. Pala Bala
