BC Insole SDK

Rust, Python, iOS, and Android SDK foundation for BrainCo smart pressure insoles.

The device protocol uses a short binary transport frame carrying Protobuf payloads:

[BRNC][Ver][PayVer][Len LE][Protobuf Payload][CRC16 LE]

Core protocol support lives in sdk/src/protocol and implements:

• CRC16-Modbus validation over header + payload
• frame encoding
• stream parsing with magic-byte resynchronization
• Protobuf request/response payload encoding and decoding

Build

cargo test

Python

cd sdk
maturin develop --features python

The Python package exposes protocol constants, BLE advertisement parsing, request builders, and an incremental stream parser. Existing parser behavior remains compatible by default. New code can preserve calibrated and raw pressure fields separately and reject CRC-invalid frames:

import bc_insole_sdk

parser = bc_insole_sdk.StreamParser(
    strict_crc=True,
    legacy_pressure_fallback=False,
)

request = bc_insole_sdk.build_sensor_stream_config_request(
    msg_id=1,
    dest_id=bc_insole_sdk.DEVICE_LEFT,
    pressure_mode="raw",
    shear_mode="calibrated",
    imu_mode="calibrated",
)

Use parser.stats() for CRC, framing, Protobuf, sequence discontinuity, and packet-loss counters.

Pressure resistance calibration and pressure-derived shear use the same Rust implementation on all platforms. Inputs are resistance values in ohms from raw_pressure; outputs are calibrated normal load and derived force vectors in newtons. Python clients call calibrate_pressure() and derive_shear(); iOS and Android wrappers bind to bcis_calibrate_pressure() and bcis_derive_shear(). Protocol-native shear_data remains reserved for future firmware use, is disabled by default, and is not used by the derived-shear calculation.

IMU protocol fields keep calibrated LSB values (acc_x/gyro_x) and raw pre-calibration LSB values (raw_acc_x/raw_gyro_x) separately. The SDK exposes physical accelerometer values in milli-g and gyroscope values in degrees per second by applying acc_scale and gyro_scale. Sensor stream configuration defaults to calibrated IMU data because the physical-value conversion uses those calibrated LSB fields.

Mobile

The Rust crate exports a C ABI with staticlib/cdylib outputs. iOS and Android wrappers should bind to the C surface in sdk/src/c.

iOS SensorStreamConfig and Android SensorStreamConfig use the same defaults as Python: raw pressure, calibrated IMU, and protocol-native shear disabled. Pressure callbacks expose both a compatibility pressure array and an explicit rawPressure array. When firmware sends raw pressure only, both arrays contain resistance in ohms; when calibrated pressure is also present, pressure contains calibrated protocol values while rawPressure remains resistance in ohms.