Comment of the Day: Wobbly Robot Edition

Today's Comment of the Day of the comes to us via a crooked path, delivered to us by a blindfolded robot. In response to a post on the difficulty humans have in walking a straight line blindfolded, commenter jshoer shares with us that robots have the same problem:

We encounter the same problem in robotic systems that rely on an inertial measurement unit (IMU), which measures the acceleration and rotation rate of a vehicle. IMUs are in all kinds of robotic navigation systems, from drones to spacecraft - not to mention smartphones. However, if the IMU is the only sensor going into a robot's control system, then any errors present will build up over time. Often, the position or orientation estimate built from IMU data looks like a random walk process. The bottom line is that the position and orientation of the vehicle will slowly drift off from where we want it to be and where we want it to point. We solve the problem of drift errors by adding sensors that measure an external reference: GPS, light sensors, radar, lidar, sonar, vision processing, and so on. You actually don't need those external references all the time; occasional, periodic "updates" are enough to correct the IMU performance sufficiently.

I'm not surprised that when a human shuts off their external references and goes by inner ear alone, the same thing happens! 24 minutes ago

Robots! They're just like you and me.

Image: Ociacia / Shutterstock