Total System for Regulation Compliance and Engine/Vehicle R&D

OBS-ONE is the latest Portable Emissions Measurement System designed for engine/vehicle certification under real road conditions.
It measures concentrations of emissions (CO, CO2, THC, NOx, NO2), particulate matter, air-to-fuel ratio, exhaust flow rate, GPS data, environmental conditions (atmospheric temperature, humidity and pressure) and calculates mass emissions.
OBS-ONE features the highly adaptable, intelligent operating platform called “HORIBA ONE PLATFORM” which integrates other ONE series product data and optimizes test cell operation.

HORIBA has developed broad emission test applications for certification and engine/vehicle R&D, such as simulating a real-world driving event in the test cell with the Test Automation System-STARS. This simulation requires data combined from the OBS-ONE and a drive recorder.



“Simple and Flexible”
Safe, User-friendly System

◎ Easy to Install

  • Easily mounted on any vehicle (modular and front access design)
  • One-touch fitting for module and cable connections

◎ Stable Operation Over Long Driving Periods

  • Low power consumption for long operation
  • Battery can be changed to AC power supply or backup battery without being powered off by using power exchange unit

◎ Safe

  • Safe in real driving without bottles (LDV type)
  • Equipped with emergency button to stop power and gas supply

◎ Accurate

  • Accurate over a variety of environmental variables (atmospheric temperature, atmospheric pressure, vibration)* 
  • UPS (Uninterruptible Power Supply) protects measurement data in the case of the battery cut-off unexpected
    *Please refer to the specification


System Configuration


Certification Test for RDE and US EPA CFR 1065 Regulation

Complies with the latest regulation requirements

PEMS Applications

◎ Measurement
Comprehensive test package includes self-diagnosis, quality check, and sensitivity calibration before testing.
Guides the entire process (preparation, measurement data post processing, etc.) from before to after testing.

[ Real-time Validation and Guidance ]
・Checks measuring data during testing to avoid invalid results
・Driver can concentrate on driving without any operation once measurement is started

◎ Data Post Processing
Complicated process of calculation and analysis made simple
・Suitable calculation and result output for LDV/HDV
・Makes test report for certification
・Shows the camera-recorded drive replay and the GPS map related to measured data
・Complies with ASAM-ODS* standard

※ASAM-ODS : Association for Standardization of Automation and Measuring Systems ー Open Data Service


Integrated Operation Software “HORIBA ONE PLATFORM”

Integrated Device Management Controller (DMC) with HORIBA ONE series products

The newly developed software for the OBS-ONE is integrated with the same operating platform as the MEXA-ONE, CVS-ONE and other devices. The intuitive, ergonomic design of the new software platform makes system operation easier. System control and a complete system view of other measurement devices are available from one single display. User support for system operation such as maintenance, alarms, and message functions has been further enhanced.

・Future expandability of PN counting and additional pollutant measurement, etc.
・User-friendly screen configuration and layout offer both measurement efficiency and convenience

OBS-ONE Device View


R&D for Engine, Powertrain and Chassis

Achieving real-world simulation in the test lab

Test Lab x Real-world

OBS-ONE provides real driving emission test as well as real driving simulation in the test lab by utilizing STARS.
This comprehensive solution ensures accurate emissions data from both real-road and laboratory testing conditions.

OBS-ONE Test lab - Real world




LDV Type

HDV Type







NO/NOx *1



NO, NOx, NO2 *2






Exhaust Flow Rate

Power Requirements

DC 22〜28 V

Power Consumption
(at stable state) *3

Approx. 0.2 kW

Approx. 0.45 kW

Dimensions *4

Approx. W 350 × D 470 × H 330 mm

Approx. W 350 × D 470 × H 470 mm

Weight (Main unit)

Approx. 32 kg

Approx. 45 kg

Battery *5

Deep-cycle, sealed lead battery of DC 24 V
35 Ah(5 hour rate),
Operation time : Approx. 3 hours

Deep-cycle, sealed lead battery of DC 24 V
100 Ah(5 hour rate),
Operation time : Approx. 4.5 hours

Operating Conditions

Temperature: -10 to 40 deg.C,*6 Relative humidity: less than 80%,
Altitude: 0 to 2000 m above sea level

Analyzers and Sensors

★NDIR : Non Dispersive Infrared Detection
 CLD : Chemiluminescence Detection
 FID : Flame Ionization Detection

Measurement Principle

Measurement Range


Heated NDIR

0-0.5 to 0-10 vol%


Heated NDIR

0-5 to 0-20 vol%

NO / NOx

Heated CLD

0-100 to 0-3000 ppm

NO, NOx, NO2

Heated-dual CLD

0-100 to 0-3000 ppm


Heated FID

0-100 to 0-10000 ppmC

Sampling Method

Wet measurement


Exhaust Fow Rate*7

Pitot flow meter

0-2.0 to 0-65.0 m3/min

Standard Signal Measurements

Exhaust temperature, Exhaust pressure, Atmospheric pressure, Atmospheric temperature, Atmospheric humidity, GPS signal, Speed

*1 NO/NOx:  Switchable measurement
*2 NO, NOx: Simultaneous measurement   NO2: Calculation of NO and NOx
*3 Length of heated inlet tube LDV type: 2 m, HDV type: 5 m, Atmospheric temperature: 20 deg.C
*4 Excluding handle and projection
*5 Nickel hydride battery is an optional unit.
*6 Please contact HORIBA if temperature is below 0 deg.C
*7 Exhaust flow rate can be taken by OBD interface unit

・OBD interface unit: Supported ISO15765-4/J1939
・External  input unit (EIU): Analog voltage, Analog current, Thermocouple, Platinum resistance temperature detector, Frequency
・Power supply unit (PS): Power supplied from AC to system
・Power exchange unit (PE): Can be changed power supply without being powered off
・Heated bubbler unit:  Humidifying unit for H2O interference check and H2O quenching effect check