Position sensing weight measuring device

An apparatus comprising:

• a communication interface;
• a platform having a first corner, a second corner, a third corner, and a fourth corner;
• a first load cell coupled to the first corner of the platform, wherein the first load cell comprises a half-bridge load cell with a first polarity having a first output;
• a second load cell coupled to the second corner of the platform that is adjacent to the first corner, wherein the second load cell comprises a half-bridge load cell with a second polarity having a second output;
• a third load cell coupled to the third corner of the platform that is adjacent to the second corner, wherein the third load cell comprises a half-bridge load cell with the first polarity having a third output;
• a fourth load cell coupled to the fourth corner of the platform that is adjacent to the third corner, wherein the fourth load cell comprises a half-bridge load cell with the second polarity having a fourth output;
• a set of switching elements having:
• a first input connected to the first output;
• a second input connected to the second output;
• a third input connected to the third output;
• a fourth input connected to the fourth output;
• a fifth output that connects to either the first input or the third input;
• and
• a sixth output that connects to either the second input or the fourth input;
• an instrument amplifier having:
• a fifth input connected to the fifth output;
• a sixth input connected to the sixth output;
• a seventh input to receive a reference signal;
• and
• a seventh output to provide an amplified difference between the fifth input and the sixth input as adjusted by the reference signal;
• and
• electronic circuitry to:
• at a first time, determine a first weight value using the first load cell and the second load cell as a first full-bridge load cell;
• at a second time, determine a second weight value using the second load cell and the third load cell as a second full-bridge load cell;
• at a third time, determine a third weight value using the third load cell and the fourth load cell as a third full-bridge load cell;
• at a fourth time, determine a fourth weight value using the fourth load cell and the first load cell as a fourth full-bridge load cell;
• determine a change in weight value that exceeds a threshold value for one or more of the first weight value, the second weight value, the third weight value, or the fourth weight value;
• and
• send, using the communication interface, data indicative of a change in weight at the platform.