qocsuing: How service robots make sense of their surroundings

qocsuing

How service robots make sense of their surroundings

Service robots play an increasingly vital role in society, from transportation and warehouse logistics to home entertainment and security. Regardless of their application, they need to sense changes in their surroundings in real-time to ensure safety while providing a positive user experience. To illustrate how various sensor technologies from TDK’s SmartSensor family can be applied in service robots, this article focuses on a robotic vacuum cleaner (RVC).To get more news about GRS, you can visit glprobotics.com official website.
Early versions of robotic vacuums had very little intelligence, randomly bumping their way around the home and sometimes missing areas as they did not know where they had been. Often, they would unwittingly become trapped or run out of charge mid-sweep. And, as their dust box is comparatively small to a regular vacuum cleaner, if full, they could be sweeping but not collecting anything up. Over the years, with the innovative use of sensors and motor controllers, vacuum cleaning robots have become much smarter, overcoming these issues.
Fundamental to any RVC is its ability to move around with a high degree of accuracy. Here, TDK’s intelligent HVC 4222F embedded motor controllers provide direct control of various stepper motors, and brushed (BDC) and brushless (BLDC) DC motors. They drive the motors that turn the gears to ensure the wheels are moving the RVC in the right direction. The high accuracy of these devices is of vital importance to ensure that the cleaner does not go off-track, whether you use sensors or not; knowing that the wheel is turning 90-degrees as opposed to 88-degrees is essential to ensure the RVC is where it thinks it is over a certain amount of time.

Ultrasonic time-of-flight (ToF) sensors, such as the CH101 and CH201, provide accurate range measurements to targets at distances up to 1.2m and 5m, respectively. They send out an ultrasonic pulse and then listen for echoes bouncing off objects in the sensor’s field of view (FoV). The built-in processing unit calculates the ToF and the external control unit determines the distance to the objects. Unlike optical distance sensors, ultrasonic sensors work in any lighting condition, including the dark, and provide millimeter-accurate measurements independent of the target’s color and can detect transparent objects such as glass.
In the robotic vacuum cleaner, the long-range CH201 can be used to detect both moving and stationary objects day and night, deviating its route well in advance to avoid a collision. The shorter range CH101 ultrasonic ToF sensor can be implemented into the robotic vacuum cleaner to determine different floor types. Here, the amplitude of the reflected signal differs if the target surface is either hard or soft. When the robotic vacuum cleaner moves from wooden flooring to a carpeted area, the sensor can instruct the motors to speed up as they need to work harder on this flooring type. These sensors can also detect whether the cleaner is at the top of a set of stairs, averting a fall.