Concept: American robotics startup Petra has unveiled its new tunnel boring robot ‘Swifty’ that can bore through hard rocks. It leverages a non-contact, thermal drilling method to bore 60-inch diameter micro tunnels through the hard rock. The robot uses machine vision micro-tunneling to bore through difficult hard rocks. The startup claims that the new robot can tunnel faster and cheaper than conventional undergrounding methods.

Nature of Disruption: Petra’s tunnel boring robot provides a safer and cost-effective method for undergrounding utilities including electricity, water, and sewage in difficult geographical regions. It offers many advantages over conventional micro-tunneling methods that include the capability to bore a range of diameters between 20-60 inches. Conventional micro-tunneling machines are purpose-built for a single diameter. The new robot offers reverse-tunneling technology which makes machine maintenance and cutter head rescue possible. Also, conventional micro tunnel boring machines (mTBM), horizontal directional drilling (HDD), and other conventional methods use cutter heads which can easily break while drilling through hard rock. Petra’s robot enables engineers to address the vulnerabilities in utility infrastructure in urban areas. The urban areas generally have large utility infrastructure lying below the soft layers of soil just below the surface. Such utility infrastructure is vulnerable and can result in disasters including pipeline explosions and water leakage due to breakdown in pipes. The new robot enables the engineers to lay the utility infrastructure through the bedrock below the existing infrastructure which can bring down the risks associated with various utilities.

Outlook: Petra’s robot enables the underground layout of utilities which can protect communities from exposure to wildfires and ensure the safety of critical infrastructure in disaster-prone areas. The new robot also enables tunneling through some of the hardest rocks in the world. In December 2021, the startup completed a pilot testing of the new robot at Sioux Quartz in the US. The robot successfully bored a 20-foot tunnel in one of the hardest rocks in the world at the rate of one inch per minute. In December 2021, the startup raised $30M in series A funding led by DCVC and participation from ACME Capital Congruent Ventures, 8VC, Real Ventures, Elementum Ventures, and Mac Venture Capital.

This article was originally published in