Work / 006 FIELD TESTING
FuelTrack-140
A twin-bore fuel meter for trucks: what the engine actually burned, and where the truck was when it burned it.
- bores, one machined block · supply and return
- of supply returns unburned on a diesel
- moving parts in the flow path
- prototype on a truck, logging now
01 · Problem
Fuel is the largest operating cost of a truck fleet, and the only major input still accounted for by tank floats, fuel-card receipts and driver logs. A probe in the tank measures the tank, not the engine: on the road the reading swings with every brake and pothole, and the averaging that tames the slosh also hides the events worth catching. A slow siphon lives inside that noise for weeks.
There is a second, less obvious hole. A diesel engine draws more fuel than it burns; the injection system sends 30 to 50% of the supply straight back to the tank. A single meter on the supply line overstates consumption by the entire return share, so “metered” fleets still argue about litres.
02 · Approach
One machined block, two bores. Bore A meters everything flowing from tank to engine. Bore B meters everything the engine sends back. Burned fuel is the difference, computed continuously:
| Channel | Direction | Measures |
|---|---|---|
| A · Supply | Tank → engine | 100% of draw |
| B · Return | Engine → tank | The 30-50% that comes back |
| A − B | · | Fuel actually burned |
Two design decisions carry the project:
- No moving parts. Dirty diesel clogs turbine and positive-displacement meters; a plain sensing bore has nothing to foul or wear. It is the same solid-state metering approach we proved on the smart pour spout, carried from single pours to a truck’s fuel rail.
- One block, one calibration. Two separate meters drift apart, and their differential drifts worse than either. Machining both bores into one body means one calibration covers the pair, and the sealed block is tamper-evident by construction.
03 · Every litre has a location
The same housing carries a GPS receiver, so burn data lands with position and time attached: litres per trip, per route, per stop. The tracking hardware is designed to the AIS 140 spec, India’s standard for commercial vehicle tracking, with certification ahead. Telemetry is store-and-forward, so highway dead zones delay a report without losing a litre.
Position plus differential flow is what turns metering into detection:
- Slow siphon: refills minus metered burn stop balancing, flagged in hours rather than at month-end.
- Return-line tap: any draw between engine and tank breaks the supply-to-return signature for that load, visible in the same run.
- Padded claims: litres per trip, route-correlated, against fuel-card arithmetic.
04 · Status
Field testing. The first prototype is installed on a working truck, metering both bores against real routes while the calibration and detection thresholds are tuned on road data. The device is built for FleetSecured, whose platform tracks commercial fleets across India; FuelTrack-140 adds the fuel truth to the map they already have.