GPS World, April 2018

TAKING POSITION Movement Grows Against Killer Robots 6 GPS WORLD WWW GPSWORLD COM APRIL 2018 Q What key aspects should product designers consider when integrating inertial technology with GPS GNSS A The availability and quality of GPS in the application is critical Industrial grade MEMS IMUs can provide survey grade performance when high quality GPS is continuously available but even tactical grade MEMS cannot provide more than a couple of minutes of GPS denied navigation The level of integration between the two technologies is also important Even comparing two systems using the same sensors the performance is highly dependent on the ability of the system designer to leverage their respective strengths A Successful integration of inertial sensors with GNSS requires understanding both the goals and environment of the application Consider the required accuracy of attitude and position severity of GNSS obstructions expected dynamics and environmental conditions Tradeoffs in size power and cost narrow the choices but achieving the desired performance is more nuanced Data sheets for IMUs can also be notoriously difficult to compare My advice is to focus on the goals and listen to the experts A There is a clear need for reliable consumer grade GNSS INS in GNSS degraded environments In this case two key aspects are removal of measurement outliers mostly caused by multipath and adequate modeling of inertial errors The first aspect is efficiently addressed via residual monitoring especially with GNSS carrier phase A 15 state INS error model is generally sufficient Yet modeling parameters and contribution of other terms such as axis misalignment must be evaluated using test data JEREMY DAVIS DIRECTOR OF ENGINEERING VECTORNAV TECHNOLOGIES RYAN DIXON CHIEF ENGINEER SPAN NOVATEL ANDREY SOLOVIEV PRINCIPAL QUNAV BY Tracy Cozzens MANAGING EDITOR T he miniature UAV sma l l e r than a human palm zips right to its human target identified through facial recognition technology and pierces the forehead with a projectile for an instant kill That harrowing scene takes place in a sevenminute viral video issued by autonomousweapons org a non profit sounding war n i n g b e l l s ov e r potential automation of weapons Its Campaign to Stop Ki ller Robots BANKILLEROBOTS s e e k s a p r eempt i v e international ban on fully autonomous weapons which enable strikes to be carried out without human intervention Allowing machines to choose to kill humans will be devastating our security and freedom warns Stuart Russel professor of computer science at the University of California at Berkeley on the video What feels like science fiction to those of us raised on the Terminator franchise could be closer than we think Because of this a new U S Army report emphasizes the need to develop countermeasures against swarming drones and other unmanned weapons The Army and U S Department of Defense have invested significantly in technologies in response to these threats often focusing on detecting radio frequency transmissions of the UAVs or their operators see page 41 for one system However as the report points out todays consumer and customized UAS increasingly can operate without radio frequency command and control links by using automated target recognition and tracking obstacle avoidance and other capabilities enabled by software The U S Army discusses the pros and cons of autonomous weapons in a June 2017 article in Military Review saying an international ban should be considered on fully autonomous weapons with missions that cannot be aborted and that cannot be recalled once they are launched If they malfunction and target civilian centers there is no way to stop them Sobering thoughts about a future that may not be too distant