RF Weight Displacement Detector

Battery-Free UHF RFID Load Sensing for Automated Stocktaking

Based on E-Garde’s RFID capacitance tag technology, the RF Weight Displacement Detector uses two internal plates and a built-in stainless-steel spring inside the tag housing to translate load into measurable displacement. As weight is applied, the spring compresses, changing the distance between the plates and thus the capacitance – this change is then captured by the RFID sensor.

Operating in the UHF RFID band, the system wirelessly transmits weight and load-distribution data without any signal or power cabling. Powered via RFID energy harvesting and completely battery-free, it minimizes maintenance effort and eliminates battery replacement.

This makes the solution particularly attractive for inventory management in factories and warehouses, where it helps reduce manual workload and significantly shortens the time required for stocktaking.

For a closer look, watch our demo video on YouTube.

Typical use case

Imagine shelves or pallets in a warehouse or factory:

• Each storage position has one of these RFID weight sensors.

• When items are placed on it, the sensor knows how much weight is there.

• A handheld or fixed RFID reader can read all sensors remotely and knows:

  • which positions are full, half full, or empty

  • how much stock is still there by weight

Result: You can do stock checks automatically, without walking around, lifting, scanning barcodes, or counting pieces – which saves a lot of time and manual work.

Key Facts

• Dimensions: 119×215×30mm

• Material: Top and bottom plates: Acrylic resin, Spring: Stainless steel

• Operating Temperature: -10℃ to 65℃

• RFID Chip: MR7930 (UHF) by ROHM Co., Ltd.

• Related Products: Dual tag / Hard tag / Circuit(open-close) Detection tag / RFID Data logger