Technical approach
Measure → Validate → Contextualise → Interpret → Recommend
Our rule: validate the measurement before relying on advice. AI and advisory must never mask measurement error. Software keeps raw measurement, processed value, validated result, derived estimate and advisory output separate at every layer.
Prototype in validation(06) Engineering
Under the record, a serious stack.
Every answer above runs on four layers: the instrument in the field, a plot-level data platform, guidance grounded in approved sources, and the people who act on it.
- Measure
- Validate
- Contextualise
- Interpret
- Recommend
01 · Field instrument
02 · Data platform
03 · Intelligence
04 · Ecosystem
Prototype architecture: every item above is a design requirement being checked through the validation gates.
Offline first
Built assuming rural network will fail.
Human review
Uncertain or high-stakes advice goes to a person.
Traceable
Every recommendation points back to its data.
Consent first
Farm data is recorded only with the farmer’s consent.
Firmware
Every scan follows one state machine.
- BOOT
- SELF TEST
- LOAD CALIBRATION
- START GNSS
- SAMPLE READY
- SCAN
- ACQUIRE
- FILTER / COMPENSATE
- QC
- CAPTURE GEO / TIME
- SAVE RAW
- SAVE PROCESSED
- DISPLAY
- OPTIONAL ADVISORY
- OPTIONAL BLE SYNC
Traceability
What every scan record must contain
This is a design requirement, not a performance claim.
- scan_id, device_id, prototype_revision, PCB_revision, firmware_version, calibration_revision
- timestamp_utc, time_source (GNSS / RTC), latitude, longitude, altitude if valid
- GNSS fix type, satellite count, HDOP / estimated accuracy, GEO status
- farmer_id, plot_id, sample_id, operator_id where available
- raw sensor values for all channels and processed values for all reported parameters
- sample temperature, ambient temperature / humidity, orientation / movement flag
- QC flags, retest flag, error codes and operator notes
QC flags
- SENSOR_TIMEOUT
- OUT_OF_RANGE
- REPEAT_FAIL
- GEO_OK
- GEO_LOW_ACCURACY
- GEO_NO_FIX
- TIME_GNSS_SYNCED
- TIME_RTC_ONLY
- WDT_RESET
- UPDATE_ROLLBACK
- LOG_CRC_FAIL
Engineering rules
The rules we do not bend.
- N, P, K sensing principle
- For each nutrient we document whether the value comes from ion-selective sensing, spectroscopy/colorimetry or a model-based estimate. Estimates are labelled as estimates everywhere.
- pH front end
- A glass pH electrode never connects directly to the MCU ADC; a dedicated very-high-input-impedance front end is required.
- Temperature compensation
- EC, pH and moisture compensation method, reference temperature and calibration revision recorded.
- Location
- Meter-class GNSS baseline. With no fix the scan is stored as GEO_NO_FIX; a stale or invented coordinate is never used. One scan is never presented as a field map.
- Data integrity
- Append-only records with CRC, partial writes rejected after power loss, watchdog recovery and firmware rollback.
- Sync
- Offline queue; repeated sync attempts never create duplicates; raw evidence is never overwritten.
- AI guardrails
- Guidance grounded in approved sources; model/rule version, confidence and a human review path. AI never invents measurement values, scheme eligibility or agronomic facts.
- On-device AI
- On-device inference with TFLite Micro is a feasibility target, not a guarantee. Mridā-AI is an internal project.
(07) Evidence
Evidence, not decoration.
MITTI SCANNER is a prototype. When each stage completes, we publish its method and result. Until then, we don’t print the number.
- G0In progress
Design review
Sensing method, pH front end, power, sample procedure and test plan reviewed.
- G1Next
Electrical bring-up
Stable rails, current measurements, programming and debug.
- G2Next
Single-sensor verification
Each channel responds; raw data retained.
- G3Next
Integrated prototype
All channels, display, storage and firmware in one assembly.
- G4Next
Repeatability
Repeated measurements of the same sample; per-parameter statistics.
- G5Next
50-sample reference-lab comparison
Scanner and lab results matched against thresholds fixed in advance.
- G6Next
Field and geo readiness
Portable power, data integrity, GNSS, BLE sync and field workflow.
What we will publish
- Per-parameter results
- After the 50-sample reference-lab comparison (G5)
- Battery and runtime
- After measured power testing
- Field outcomes
- After multi-season pilots
Company
- The Mitti Tech Private Limited · Est. 2026
- Lucknow, Uttar Pradesh
- DPIIT-recognised startup · Certificate DIPP272273
- StartInUP-recognised
- Stage: prototype, validation in progress
50-sample comparison
Pass marks fixed before we see results.
The 50-sample set is an initial engineering validation, not a single headline percentage. Before testing we freeze the reference-lab method, sample-selection rule, per-parameter metrics (MAE, RMSE, bias) and acceptance thresholds. Failed runs are logged, never silently discarded.
Result table (filled after testing)
उदाहरण / Example- N
- Not yet tested
- P
- Not yet tested
- K
- Not yet tested
- pH
- Not yet tested
- EC
- Not yet tested
- Moisture
- Not yet tested
- Temperature
- Not yet tested
Help build the validation
If you work in hardware, firmware, soil science, GIS or reference testing, get in touch.

