FULLY INTEGRATED PC VERSION

METS® Applications

The PC version of the Jodon microwave engine timing system offers many benefits and features not available on the original METS® unit. The new system employs contemporary microprocessor technology in a lightweight, fully integrated “tabletop” unit.

The Jodon microwave process involves introducing a low power microwave signal into a reciprocating engine cylinder for use in timing or phasing of engine operating parameters related to fuel economy, running smoothness, performance, and exhaust emissions. The system is suitable for use with Spark Ignition (SI) or diesel engines, in all modes of operation. The system can also be used to time or phase events on non-traditional engines such as rotary and Stirling engines.

The uniqueness of the Jodon process is the ability of the system to accurately time engine events with respect to the traditional Piston Top Dead Center (TDC) reference. A precise measurement of piston motion is made in real time, with the engine running (or cold-motored) at virtually any engine speed. Knowledge of the instantaneous position of the piston, in any of the engine’s cylinders, allows a precise determination of the phase relationship of critical cyclic events with respect to the location of piston TDC.

HOW THE SYSTEM OPERATES
The METS® process eliminates the need to mechanically calibrate the crankshaft rotary motion, or to use damper notch pick-ups with their inherent inaccuracies. The system is interfaced to the engine using a microwave coaxial cable. Entry into the cylinder head is made through the use of a diesel probe (IDI or DI versions), or a Spark Plug Adapter (SPA) for SI engines. Using the SPA, the microwave signal enters the cylinder through a functioning spark plug. A rotational reference input to the METS® is obtained using a ring gear sensor, or commonly for contemporary engine designs, an integral crankshaft “code wheel” reference.

The remaining METS® digital inputs (3) are for engine event signals such as a fuel injector control pulse (SI or diesel engines), a fuel line pressure sensor (diesel), or an ignition HV lead sensor (SI). A typical first-time hookup for a new engine type requires several minutes to select and save required engine test parameters. Then, for subsequent use on that engine type, system setup requires only a minute or two.

With the system attached to the test engine, the process is quick and easy. Answer a few questions on the prompter menu and start the engine. The METS® process can be initiated at virtually any engine speed, and the timing results are presented within a few seconds. With TDC found, and the timing value(s) displayed, ramp the engine speed up or down and the METS® will faithfully track the speed-related timing schedule. Three engine events can be tracked simultaneously, with accuracies which are impossible to obtain using any other known process.

SYSTEM DESIGN CONSIDERATIONS
The PC version of the METS® incorporates a person-portable unit in a small “suitcase” format. The “suitcase” includes the microwave system, a ruggedized laptop PC, all sensors, and all interconnecting cables. The complete unit weighs approximately 40 pounds (18.2 Kg). While the reduced size of the new system is impressive, the operating performance has also been improved significantly. The determination of the complete phase relationship between critical engine events, within a few seconds, speaks volumes about the power and versatility of the integral microprocessor (PC). Further, the PC permits the operator to view on the monitor the microwave waveform, and the timing of all phased events (e.g., ignition, ring-gear or code wheel, fuel line pressure pulses, engine control event pulses, etc.). These displays are especially helpful in understanding the various phase relationships and for performing effective diagnostic interpretations.

SYSTEM CAPABILITIES
The unique computer controlled Variable Frequency Oscillator (VFO) of the METS® design enables the system to be mated to virtually any reciprocating engine. With a VFO range of 8-18 GHz, cylinder volumes as large as one liter, and more, can be accommodated. It is truly a broad spectrum system with few operating limitations.

It can precisely determine:

• Piston TDC (any cylinder or all cylinders) on 4-stroke or 2-stroke engines, hot running or cold motored
• SI engine event timing
• Diesel engine injection timing
• Engine control module (ECM) event timing
• Engine “code wheel” tooth timing
• Timing of a single pulse within a multi-pulse cyclical signal
• Cylinder-averaging timing of a multi-pulse cyclical signal
• TDC phasing of cylinder pressure reference event
• Ring gear or “code wheel” waveform analysis
• Intra-cycle engine speed variation analysis (an indication of relative cylinder power balance)
• Spark (or injection process) scatter analysis

OPTIONAL CAPABILITIES:

• Auto-mapping process
• SPC functions
• Compression ratio (CR)
• Minimum Cylinder Volume (MCV)

Typical METS® display showing RPM, timing, and 720° of microwave data
System type: Dynamic engine event timing measurements with respect to piston TDC.

Microwave oscillator: Computer-tuned VFO, 8-18GHz, 10-50 milliwatts

Method of Measurement: Introduce microwave energy into a single cylinder and use the resulting piston modulation effects to determine the location of piston TDC.

Angularly correlate any cyclical engine events to the measured piston TDC.

Computer (minimum):
Configuration: Laptop, ruggedized
CPU: Intel Pentium III®
RAM: 128MB
Hard Drive: 10GB
Floppy Disk: 3.5 inch, 1.44MB
Auxiliary Drive: 24X CD-ROM
Monitor: Flat panel, TFT, 13.3 inch
Input: Keyboard and touchpad

Engine Compatibility: Virtually all SI and diesel engine designs with reciprocating piston motion, 4-stroke or 2-stroke, 1 to 12 cylinders.

Performance:
Timing resolution: 0.1 c/s degrees
Timing accuracy: ±0.2 c/s degrees
Timing channels: 3 digital inputs, rising or falling edge
Time to find TDC: 1 to 2 seconds, RPM dependent

Operating Compatibility: Hot running or cold-motored. Power: 100/110/220 VAC, 50/60Hz
Engine RPM Range: 400 to 8000 (to 4000 RPM for initial TDC location) Temperature Limits: 2 to 41° C