There is a festival in India so amazing that millions of people attend every year – despite the near certainty that many will die. Nilay Kulkarni grew up hearing the horror stories of human stampedes that claimed hundreds of lives annually. With a desire to prevent what seemed inevitable, the guiding voice of his grandfather, a hackathon, and a set of black rubber mats, Kulkarni took on human stampedes. This episode of ‘Fixed That For You’ combines the science of crowd control with the power of a lifesaving DIY data collection tool. Kulkarni was the co-founder and CTO of Ashioto Analyitcs, a real-time crowd flow analysis platform. Check out more about Kumbh Mela, one of the biggest festivals in India. Curious to learn more about crowd safety? Keith Still is a professor of Crowd Science at Manchester Metropolitan Univerisity. Build something with your own Arduino board.