Significance and Use
4.1 This section provides a description of the environmental conditions listed in Section 1 and describes the sub-conditions within each condition. Examples provided for many of the conditions and sub-conditions are provided as guidance only. Each of the conditions described should be evaluated and documented as set forth in Sections 5, 6, and 7.
4.2 Environmental Consistency: Static, Dynamic, Transitional:
4.2.1 Static is when the environment is similar throughout the test apparatus. For example, there are minor fluctuations in temperature throughout the apparatus as shown in Fig. 1 and Fig. 2. Dynamic is when the environment significantly differs within the test apparatus. For example, when the temperature changes between repetitions as shown in Fig. 3. Transitional is when the environment significantly differs in different areas within the test apparatus as shown in Fig. 4. The intent here is to not give specific guidance, but to provide a high-level classification of a particular set of environmental conditions. If environment consistency is dynamic or transitional, or both, a report form (see Section 7) for each unique set of environmental conditions should be completed.
FIG. 1 Example of Static Environment using Temperature
FIG. 2 Example of Static Environment using Temperature and Showing a Transition between Two Static Environments
FIG. 3 Example of Dynamic Environment using Temperature and Showing that the Environment Changed during the Test
FIG. 4 Example of Transitional Environment using Temperature; Portions of the Environment May Remain Static or May Be Dynamic (for example, Cold to Colder)
4.3 Lighting:
4.3.1 Various lighting conditions can potentially affect A-UGV optical sensor performance by affecting sensor and in turn, A-UGV responsiveness. Lighting sources can include ambient lighting as well as light emitters associated A-UGV operation. Two setups for lighting include direct or ambient source(s) applied to the A-UGV. Direct lighting can also include reflected light from a highly reflective surface and implies that the source is directed at the light-affected components of the A-UGV (for example, sensors). Indirect or ambient light includes lighting where the source is not directly applied to the light-affected components of the A-UGV. Light intensity is divided into five levels exemplified through dark, dim, typical indoor lighting, spotlight, and full sunlight.
4.3.2 Ambient Lighting Type:
4.3.2.1 Exposed bulb (for example, fluorescent, can lights),
4.3.2.2 Spotlight (for example, direct away from the A-UGV),
4.3.2.3 Sunlight (for example, the A-UGV is tested in bright sunlight),
4.3.2.4 Reflected (for example, bulb directed at the ceiling),
4.3.2.5 Filtered (for example, diffused light through translucent glass).
4.3.3 Directed Lighting Type:
4.3.3.1 Exposed bulb,
4.3.3.2 Spotlight,
4.3.3.3 Sunlight (for example, the A-UGV faces/navigates towards low sun position),
4.3.3.4 Reflected,
4.3.3.5 Filtered,
4.3.3.6 Laser,
4.3.3.7 Light from another vehicle.
4.3.4 Lighting Source Location—Document indirect and direct light source location and elevation with respect to the A-UGV (refer to Fig. 5).
FIG. 5 Lighting Direction (a) Top View and (b) Side View and (c) Elevation View with Respect to the A-UGV
4.3.5 Lighting Levels:
4.3.5.1 Level 1: 0 to 1 lux (for example, dark).
4.3.5.2 Level 2: 2 to 99 lux (for example, dim).
4.3.5.3 Level 3: 100 to 1000 lux (for example, office environment).
4.3.5.4 Level 4: 1001 to 9999 lux (for example, high intensity work light, spotlight).
4.3.5.5 Level 5: 10 000 lux and above (for example, full sunlight).
4.3.6 Spectrum—Identify primary color and peak wavelength.
4.3.7 Polarization—Identify the polarizing source and angle with respect to a known reference (for example, world coordinates).
4.3.8 If more specificity of measurement is required, the following documents and standards may be used: “Recommended Light Levels” from the National Optical Astronomy Observatory9 and ISO 15469.
4.4 External Emission:
4.4.1 When emitters are outside of the A-UGV (for example, from another A-UGV, the environment) that can potentially interfere with the A-UGV sensor system. External radiation sources can affect the A-UGV performance, for example: multiple time-of-flight cameras, fork-lift pedestrian lights, 3D structured light sensors, light detection and ranging sensors (LIDAR).
4.4.2 External Emitter Configuration:
4.4.2.1 Type of emitter(s).
4.4.2.2 Quantity of emitter(s).
4.4.3 External Emitter Source Location—Document emitter source location and elevation with respect to the A-UGV (refer to Fig. 5); add an external emitter symbol on the test method drawing in the appropriate location.
4.4.4 Spectrum—Identify primary color and peak wavelength.
4.5 Temperature:
4.5.1 Temperature variability and extremes can affect the A-UGV performance. Temperature ranges span from low to high extremes expressed in five levels. Temperature variations can affect onboard electronics, create condensation, cause hydraulic fluid viscosity, reduce battery life and recharge rate.
4.5.2 Temperature Levels (in °C):
4.5.2.1 Level 1: below 0°C to 0°C (for example, freezer).
4.5.2.2 Level 2: 0°C to 15°C (for example, perishable storage).
4.5.2.3 Level 3: 16°C to 26°C (for example, office, warehouse).
4.5.2.4 Level 4: 27°C to 49°C (for example, warehouse).
4.5.2.5 Level 5: above 49°C (for example, foundries, forges).
4.6 Humidity:
4.6.1 Humidity refers to the amount of water vapor contained in the air around the vehicle. High humidity combined with dew point temperature causes condensation that can short electronics and affect lenses and other A-UGV components. Greater than 60 % humidity causes a large increase in corrosion of metallic parts. Low humidity, on the other hand, will see a dramatic rise in static electricity and the need for adequate discharge.
4.6.2 Relative Humidity Level:
4.6.2.1 Low – less than 30 %.
4.6.2.2 Moderately Low – 31 to 55 %.
4.6.2.3 Moderately High – 56 to 75%.
4.6.2.4 High – greater than 75 %.
4.6.3 Dew Point Temperature—The highest temperature at which airborne water vapor will condense to form liquid dew.
4.7 Electrical Interference:
4.7.1 Some surfaces are not conductive enough to provide adequate grounding for an A-UGV. Ground vehicles have a floating electrical ground. As static builds up on the vehicle and the voltage drop from the positive lead of the battery and the chassis changes, the electronic components of the vehicle are negatively impacted. Strong magnetic fields can impact the onboard electrical components, and in particular, any data storage within the onboard computer. Many A-UGVs require wireless network connections for full functionality. Radio frequency (RF) interference can degrade these networks and A-UGV capability.
4.7.2 For Electro-magnetic compatibility issues, refer to:
4.7.2.1 BS EN 12895 Electromagnetic Compatibility – Emissions and Immunity.
4.7.2.2 MIL-STD-462 – EMI Emissions and Susceptibility.
4.7.2.3 IEC 61000-4-1 Electromagnetic Compatibility (EMC) – Part 4-1: Testing and Measurement Techniques – Overview of Immunity Tests
4.7.2.4 IEC 61000-6 – Emission Standards for Industrial Environments
4.8 Air Flow and Quality:
4.8.1 Air flow and quality refers to the ability that an A-UGV can discern an object or light in the presence of air particulates or wind, or both. Air quality can affect the A-UGV performance in terms of object detection, navigation, and docking. Air quality depends upon the size and volumetric density of particulates in the air. For relative comparison, the average human eye cannot see particles smaller than 40 μm, fog from water vapor typically includes particle sizes from 5 μm to 50 μm, and dust particles are typically 0.1 μm to 100 μm. An ISO Class 1 cleanroom has no more than 10 particles larger than 0.1 μm in a cubic meter of air. Fog (water vapor) particle density of 1 amg allows human visibility of about 125 m at ground level.
4.8.2 Air Velocity and Direction—Document air flow source location and elevation with respect to the A-UGV (refer to Fig. 5).
4.8.3 Air Particle Density—Optionally, measure the air particle size and volumetric density.
4.8.3.1 Clear – (for example, clean room, no visible air particulates).
4.8.3.2 Moderate – (for example, visible fog, dust, light to moderate rain/snow/fog).
4.8.3.3 Dense – (for example, dust storm, heavy snow/rain/fog).
4.8.4 If more specificity of measurement is required, the following standards may be used:
4.8.4.1 Air particle density – Clear: ISO 14644-1.
4.9 Floor or Ground Surface:
4.9.1 A-UGV mobility is affected by ground surface conditions including: surface texture/roughness, deformability, sloped (ramp) or undulation (lack of flatness). Ground surface conditions can affect A-UGV: traction, vibration affecting the electronics integrity, positioning, and stability.
4.9.2 Type(s):
4.9.2.1 Approximate similar to the following examples where multiple floor types may be present and indicated on the report form: for example, concrete, linoleum tile, carpet, dirt, grass, asphalt, wood plank, etc.
4.9.2.2 Indicate floor anomalies within the test space: for example, floor grate, manhole cover, undetectable (by vehicle sensors) divots, transparent flooring, etc.
4.9.3 Coefficient of Friction:
4.9.3.1 High (for example, brushed concrete, asphalt).
4.9.3.2 Moderate (for example, polished/sealed concrete, steel plates, packed dirt).
4.9.3.3 Low (for example, icy, wet, lubricated, dry sand).
4.9.4 Gap/Step—Known infrastructure that could be a part of the A-UGV map (see Fig. 6).
FIG. 6 Gap and Step
4.9.4.1 Gap—Length, width, depth, and angle of gap with respect to a reference frame.
4.9.4.2 Step—Length, width, depth, and angle of step with respect to a reference frame.
4.9.4.3 For each gap/step, a description of the gap/step should also be documented. Examples: sharp gap (between loading dock and truck) vs. rounded gap (pothole, floor divot); sharp step (square channel metal) vs. rounded step (cable or cable cover, speed bump/hump).
4.9.5 Deformability:
4.9.5.1 Rigid (for example, concrete, asphalt).
4.9.5.2 Semi-rigid (for example, compacted dirt or gravel, wet sand, industrial carpet).
4.9.5.3 Soft – malleable (for example, snow, mud, dry sand, padded carpet).
4.9.6 Grade (Ramp)—Known infrastructure that could be a part of the A-UGV map.
4.9.6.1 Level 1*: 0 % to 3 % (for example, nominally flat floor).
4.9.6.2 Level 2*: 4 % to 7 % (for example, transitional ramp in factories).
4.9.6.3 Level 3: 8 % to 10 % (for example, yard ramp = 8 % to 9 %).
4.9.6.4 Level 4: 11 % to 15 % (for example, steep road grade).
4.9.6.5 Level 5: 16 % and above.
Note 1: ITSDF B56.5 defines a ramp as “a variation in floor grade in excess of 3 % and of a length where rating data variance is required.” UL 3100 Section 16.1 states “The AGV shall be capable of meeting all requirements for operation and control on an even grade and a sloped grade up to 3 % of grade.”
4.9.7 Undulation (Lack of Flatness on the Apparatus Ground Surface):
4.9.7.1 Flat – 0 mm to 6 mm variation over 3 m.
4.9.7.2 Moderately flat – more than 6 mm to 12 mm variation over 3 m.
4.9.7.3 Non-flat – more than 12 mm to 51 mm variation over 3 m.
4.9.7.4 Outdoor – more than 51 mm variation over 3 m.
4.9.8 Particulates (document type and describe):
4.9.8.1 None (for example, dry, clean).
4.9.8.2 Fine (for example, cardboard dust, concrete dust).
4.9.8.3 Coarse (for example, sand, pebbles).
4.9.9 If more specificity of measurement is required, the following standards may be used:
4.9.9.1 Deformability: ASTM Test Method E1274.
4.9.9.2 Undulation: ASTM Test Method E1155M.
4.9.9.3 Coefficient of Friction: ANSI B101.3.
4.10 Boundaries:
4.10.1 Boundaries refer to the defining apparatus, existing structure, or ground anomalies, or combinations thereof, within which the A-UGV navigates. The characteristics for boundaries include:
4.10.2 Opaque walls (for example, white drywall, opaque plastic, reflective or flat black test boundaries, corrugated metal, curb from the road).
4.10.3 Semi-transparent walls – (for example, clear glass, frosted glass, translucent plastic).
4.10.4 Negative obstacles (for example, cliff, curb from the sidewalk, loading dock, drainage channel).
4.10.5 Virtual walls (for example, A-UGV prohibited areas mapped within the vehicle controller at edges of pedestrian walkways, edges of negative obstacles, restricted areas).
4.10.6 Porous walls (for example, wire mesh fencing, chain-link fencing).
4.10.7 Elevated dividers (for example, racking, post and beam fencing, retractable-belt dividers).
4.10.8 Building infrastructure (for example, machinery, equipment, A-UGV chargers).
4.10.9 Floor markings (for example, tape, paint).
4.10.10 Mixture of the above boundaries (for example, railing and kickplate in front of a negative drop-off at edge of a platform, post and beam fencing with wire mesh covering).
4.10.11 Moving boundaries (for example, moving sliding or hinged doors, moving curtains); the environment should be labeled as static unless the boundary moves during a test, in which case the environment should be labeled as dynamic, for example, an A-UGV drives past a soft partition that moves or an A-UGV drives through a soft partition that causes it to move.
4.10.12 If more specificity of measurement is required, the following standards and references may be used:
4.10.12.1 Floor Markings:
(1) Automotive Industry Action Group (AIAG) Occupational Health and Safety OH-2, Pedestrian and Vehicle Safety Guideline (includes description and marking depictions).
(2) ANSI/ITSDF B56.5 (section 8.11.2 describes Hazardous Zones).
(3) “Implementation of 5S Quality Tool in Manufacturing Company: A Case Study.”10
Scope
1.1 When conducting test methods, it is important to consider the role that the environmental conditions play in the Automatic through Autonomous – Unmanned Ground Vehicle (A-UGV) performance. Various A-UGVs are designed to be operated both indoors and outdoors under conditions specified by the manufacturer. Likewise, end users of the A-UGV will be operating these vehicles in a variety of environmental conditions. When conducting and replicating F45 test methods by vehicle manufacturers and users, it is important to specify and document the environmental conditions under which the A-UGV is to be tested as there will be variations in vehicle performance caused by the conditions, especially when comparing and replicating sets of test results. It is also important to consider changes in environmental conditions during the course of operations (for example, transitions between conditions). As such, environmental conditions specified in this practice are static, dynamic, or transitional, or combinations thereof; with the A-UGV stationary or in motion. This practice provides brief introduction to the following list of environmental conditions that can affect performance of the A-UGV: Lighting, External sensor emission, Temperature, Humidity, Electrical Interference, Air quality, Ground Surface, and Boundaries. This practice then breaks down each condition into sub-categories so that the user can document the various aspects associated with the category prior to A-UGV tests defined in ASTM F45 Test Methods (for example, F3244). It is recommended that salient environment conditions be documented when conducting F45 test methods.
1.2 The environmental conditions listed in 1.1 to be documented for A-UGV(s) being tested are described and parameterized in Section 4 and allow a basis for performance comparison in test methods. The approach is to divide the list of environmental conditions into sub-conditions that represent the various aspects of the major category (for example, sunlight within ambient lighting). Where necessary, this practice also provides guidelines (for example, lighting direction) to document environmental conditions in an existing environment.
1.3 The values stated in SI units are to be regarded as the standard. The values given in parentheses are not precise mathematical conversion to imperial units. They are close approximate equivalents for the purpose of specifying material dimensions or quantities that are readily available to avoid excessive fabrication costs of test apparatuses while maintaining repeatability and reproducibility of the test method results. These values given in parentheses are provided for information only and are not considered standard.
1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.
1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.
