Dayu Electronics: Ultrasonic Dual-Transducer Distance Measurement Solution for Trash Can Overflow Alerts

Recently, an intelligent sanitation equipment integrator raised the following ultrasonic distance measurement requirements:

Application scenario:

Install a sensor on the inner side of the top cover of an outdoor trash can, measuring the waste accumulation height downward, for overflow alarms and collection scheduling.

01 Customer requirement: Install on top of trash can, measure waste height

Customer requirements       Specific specifications

Range                 ≤2 m

Blind zone             ≤0.1 m (can recognize waste within 10 cm of the transducer)

Accuracy              When waste is located 10 cm from the trash can opening, its height can be accurately identified, with low false alarm rate (no frequent false alarms)

Environmental interference  Possible water, sand, and dust inside the can

Installation constraints   Mounting hole diameter at the bottom is only 8 cm; sensor dimensions must not exceed this size

Output                 RS-485 (Modbus protocol), connected to IoT gateway

                                      (Schematic diagram; actual conditions prevail)

Customer's previous attempts failed: a single-transducer ultrasonic sensor from a certain brand

Blind zone about 25 cm (cannot detect nearby waste)

High false alarm rate when water accumulates

Housing diameter >10 cm (cannot fit into 8 cm hole)

02 Problem analysis: Why does a single-transducer sensor tend to fail in this condition?

1. Large blind zone, 25 cm

The single-transducer blind zone is about 25 cm, making it unable to detect nearby waste, so the trash can is not fully utilized, and effective capacity decreases.

The dual-transducer ultrasonic distance sensor can achieve a blind zone within 10 cm, making nearly full-overflow detection possible.

2. Large size

The single-transducer unit is relatively large, unattractive when installed on the lid, and difficult to integrate with the trash can.

The dual-transducer distance sensor has an overall height of ≤5 cm, with a flat design that can be embedded for a neat appearance.

3. Insufficient protection rating

The single-transducer protection rating is typically IP65 or IP66, which is not reliable enough for long-term use in trash cans.

The dual-transducer distance sensor has an IP68 protection rating, meeting the requirements for long-term outdoor trash can use.

4. High power consumption

The single-transducer RS-485 output type requires 24V/60mA; the dual-transducer only requires 12V/40mA, making it more suitable for battery-powered scenarios.

Conclusion: In the specific scenario of trash can overflow detection, the dual-transducer distance sensor has more advantages than the single-transducer sensor.

03 Dayu Electronics ultrasonic dual-transducer distance measurement sensor