Epson Electronics supports navigation solutions for smart pool cleaning robots

Pool Cleaning Navigation Program

Currently, pool cleaning robots have become a new hot track, and many companies have invested in research and development in this new field, mainly companies that used to be engaged in household sweeping robots, because the intelligence of pool cleaning robots is similar to the intelligent path of previous sweeping robots, and is still in the initial stage of technology.

The same part as the household sweeping robot is that the current pool cleaning robot mainly walks randomly without path planning, and the cleaning efficiency is low. In the future, it will soon enter the planning era. The difference is that the environment in the swimming pool is completely different from the working environment of the household sweeping robot, and the navigation method cannot adopt the current mainstream laser navigation or visual navigation method. In the future, it may mainly use inertial navigation + ultrasonic as the main navigation method. At present, ultrasonic radar is mainly used for obstacle avoidance and other functions, so the most reliable method that can be mainly used for the navigation of pool cleaning robots is still inertial navigation .

First, let's analyze the working environment of the pool robot. The pool robot's main work is to clean the bottom and walls of the pool. Since the general acceleration can provide very clear data on the pitch angle, and the function is similar to that of the window cleaning robot in the past, there are not many technical difficulties in cleaning the wall. Since the pool robot needs to go up to the wall, it cannot be set with a front collision switch like a household sweeper in terms of structure. Therefore, the wall is generally judged based on the pitch angle change caused by the pool robot climbing up the wall, resulting in a pitch angle change every time the robot hits the wall.

Frequent changes in pitch angles will cause greater interference to the accuracy of yaw angles, so the pool robot not only requires high precision on the Z axis, but also on the X and Y axes. Regarding working time, a general household swimming pool is about 20 to 50 square meters. Although the area is relatively small, the movement speed of the pool robot is also relatively low, generally 10CM/SEC, which is about one-third of that of a household sweeping robot. It takes about 1 hour to clean the bottom of a 30-square-meter swimming pool, so inertial navigation also requires high precision for the gyroscope.

If ultrasonic sensors are used to solve the problem of the robot not having to climb walls, then this requirement can be met by using a gyroscope on the Z axis. The technical solution is the 1+6 solution that inertial navigation sweeping robots used to use, which is 1 Epson high-precision gyroscope + 1 6-axis gyroscope sensor . If the robot needs to climb walls frequently, this solution is not suitable and a higher-end IMU is needed for navigation. Considering the cost requirements, Epson has developed the SGPM01 series gyroscope module in cooperation with a third party . In actual measurements in such working environments, it can achieve a 5-degree deviation in 1 hour *, which can meet the general requirements of the industry.

About SGPM01 Series Gyroscope Module

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describe:

SGPM01 is a module developed based on high-performance gyroscope sensors, accelerometers and magnetometers, with built-in 3-axis gyroscopes, 3-axis accelerometer sensors and 3-axis geomagnetic sensors.

Relying on high-precision sensors, high-performance and advanced processing, it outputs very stable angular velocity values, acceleration values, magnetometers and attitude angles. The module can support SPI data communication. The overall product size is: 24*22*8mm

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Product Features

▋High-precision 9-axis gyroscope module

▋Output three-axis acceleration value, three-axis angular velocity value, three-axis geomagnetic, attitude angle (tch, Roll, Yaw), temperature

▋Digital Communication UART and SPI

▋Product size: 24*22*8mm

▋Low power consumption

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*Product data comes from a third-party laboratory and may differ from actual data due to different usage and settings.

Review editor: Liu Qing