Section 2 – Requirements

2.1 Manufacturer Provided Equipment

The following equipment shall be provided by the lidar unit’s manufacturer to the test laboratory, as applicable. Such equipment shall remain the property of the lidar unit’s manufacturer and be returned upon completion of testing unless other agreements are made.

The manufacturer of a lidar device or lidar system who is requesting approval of a characteristic that is outside the specifications contained in this document is required to provide suggested revisions for review by the appropriate IACP Highway Safety Committee designee when submitting the UUT. The manufacturer shall supply any adapters or unique test equipment required to test the UUT.

2.1.1 Tripod Adapter. In parts of the acceptance testing, a tripod must be used to steady the lidar unit. If a lidar unit requires an adapter for mounting to a tripod, the manufacturer shall furnish the adaptor.

2.1.2 I/O Port Test Setup. If the lidar unit features an I/O port for output that is claimed to meet a standard such as RS-232, the manufacturer shall supply the cabling and simple software with which the test laboratories can connect the UUT to a PC-compatible computer or other intended device and test the operation of the I/O port. In this context, "simple software" means a short program in a high-level language such as BASIC or C, with source code supplied. The purpose of this software is to verify the operation of the port, and it may be different from proprietary software provided for police use.

2.1.3 Switching Output Indicator Box. If a switching output is claimed, the manufacturer shall supply the test laboratories with cabling and a simple indicator box which can be used to verify this output. The indicator box, which might contain such parts as a battery, a resistor, and an LED, shall be accompanied by a schematic and shall make the voltage at the switched pins accessible for measurement.

2.1.4 Remote Control Test Setup. If remote control by computer is claimed, the manufacturer shall supply the cabling and simple software with which the test laboratories can connect the UUT to a PC-compatible computer and test the data input functions. In this context, "simple software" means a short program in a high-level language such as BASIC or C, with source code supplied. This simple software may be different from proprietary software provided for police use. If the simple software does not exercise all remote-control functions and proprietary PC-compatible software is available for this purpose, that software shall also be supplied. Source code of the proprietary software is not required.

2.1.5 Remote Trigger Test Setup. If the unit to be tested has a remote trigger input in lieu of or in addition to a remote control port, the manufacturer shall provide a switch box and cable to the test laboratories. The switch box shall have parts that are visible and electrically accessible for testing. If the switch box incorporates parts beyond a switch, a schematic shall be supplied.

2.1.6 Receive-Send Unit. This specification requires the lidar unit to be tested on a target simulator, which may return light pulses of a different shape and energy level from those of a real target. Each lidar device submitted for testing must interact properly with the simulator. The manufacturer may, at its option, supply the receive-send unit to be used with its lidar device; or it may supply an interface, perhaps employing fiber optics, to deal with the optical aspects of the receive-send interface.

2.2 Manufacturer Provided Information

Each lidar device submitted for testing in accordance with the provisions of these specifications shall be accompanied by the following minimum information:

2.2.1 Complete Operating Instructions. This includes test procedures, required maintenance, and any operating characteristics that are indicative or symptomatic of possible malfunction of the lidar unit.

2.2.2 Laser Wavelength. The operating wavelength of the lidar unit.

2.2.3 Laser Safety Classification. The lidar unit is regulated by the Center for Devices and Radiological Health (CDRH) of the Food and Drug Administration (21 CFR 1040.10 and 1040.11 or as amended).

2.2.4 Nominal Power Supply Voltage and Currents. Separate current values for different operating states, as appropriate.

2.2.5 Supply Voltage Limits. The lowest and highest supply voltages at which the lidar unit is designed to operate, the low voltage alert threshold value and display behavior.

2.2.6 Image Recording Equipment. The image recording equipment shall be submitted to support testing where applicable. The image recording equipment submitted for testing in accordance with the provisions of these specifications shall be accompanied by the following minimum information:

2.2.6.1 Installation instructions. Complete instructions for connecting the supplied equipment to the lidar device and verifying their operation, including test procedures, required maintenance, and operating conditions indicative or symptomatic of a possible malfunction of the lidar system.

2.2.6.2 Operating instructions. Complete instructions for operating the supplied equipment.

2.2.7 Speed Measurement Range. Expressed as the highest and lowest speeds that can be measured by the lidar unit for approaching or receding targets.

2.2.8 Temperature Limits. The highest and lowest temperatures at which the lidar system is designed to operate.

2.2.9 Temperature-Humidity Limit. The highest temperature and humidity combination at which the lidar system is designed to operate.

2.2.10 Reference Plane. The plane on the lidar unit from which distance measurements are taken. If not stated, the reference plane is assumed to be the front surface of the device.

2.2.11 Horizontal and Vertical Functional Beamwidths. Functional beamwidths shall be stated in milliradians.

2.2.12 Triggering. A description of when the lidar unit should be triggered during the operational speed accuracy test. The operational speed accuracy test depends on a baseline on the ground, for instance two marks approximately 400 m (¼ mile) apart. The lidar should be triggered so that it measures the speed over nearly the same baseline each time the measurement is repeated. This may involve triggering the lidar unit as the test vehicle begins to traverse the baseline, or tracking the vehicle and releasing the trigger at a certain point. Due consideration must be made to coordinate the lidar speed reading with readings of the certified radar unit, the test vehicle’s speedometer and the average speed (stopwatch-timed distance) of the test vehicle as set forth in § 5.15.2.

2.2.13 Pulse Repetition Rate. The Manufacturer shall provide the pulse repetition rate (PRR).

2.3 Manufacturer Labeling

The control panel of the lidar device shall be permanently marked with the functions and settings of all switches, controls, and displays. It shall not be possible to set the controls to a functional mode of operation that is not explained in the user manual. Every control shall be labeled, and the labeling shall, at a minimum, be consistent with one of the functions of the control (§5.3).

2.4 Range Accuracy

For a baseline distance between 6 m (20 ft) to 30 m (100 ft) and for a baseline distance at least 90 m (300 ft), the target range reading shall be correct to within ± 0.3 m (±1 ft).

2.5 Long Range

The lidar unit shall be capable of measuring distances of at least 300 m (1000 ft).

2.6 Beam Characteristics

2.6.1 Beam Alignment. The transmitted beam and the sighting optics of the lidar unit shall be properly aligned, both horizontally and vertically, in accordance with
§5.6.1.

2.6.2 Range. The lidar unit shall accurately display the range of each presented target as measured in accordance with § 5.6.2.

2.6.3 Target Discrimination. The functional beamwidth of the lidar unit shall not exceed 5 mrad as tested in accordance with §5.6.3.

2.7 Environmental Extremes

Any lidar system not enclosed in an environmentally-controlled cabinet shall be tested to determine the ability of the lidar system to operate in environmental extremes using the test methods described in §5.7. Lidar systems in an environmentally enclosed cabinet shall be certified by the manufacturer to comply with (§2.7.1.1) and (§2.7.2).

2.7.1 Operational Temperatures

2.7.1.1 Lidar Device Temperature Limits. Let TdLow be defined as -30 ºC (-22 ºF) or the lowest temperature at which the manufacturer states that the lidar device will operate properly (§2.2.7), whichever is lower. Let TdHigh be defined as 60 ºC (140 ºF) or the highest temperature at which the manufacturer states that the device will operate properly (§2.2.7), whichever is higher. Then, when tested in accordance with §5.7.1, following exposure to TdLow or TdHigh, each lidar device shall continue to be able to generate speed reading that meet the speed accuracy requirements of §2.11.

2.7.1.2 Lidar System Temperature Limits. Let TsLow be defined as the lowest temperature at which the manufacturer states that the lidar system will operate properly (§2.2.7). Let TsHigh be defined as the highest temperature at which the manufacturer states that the lidar system will operate properly (§2.2.7). Then, when tested in accordance with §5.7.1, following exposure to TsLow or TsHigh, each lidar system shall continue to be able to generate speed reading that meet the speed accuracy requirements of §2.11. In addition when a lidar system is tested in accordance with §5.7.1, following exposure to TdLow or TdHigh, the lidar system shall not generate any erroneous speed readings. During these tests, a blank target speed display is not an erroneous reading.

2.7.2 Operational Humidity. When tested in accordance with §5.7.2 following exposure to 90 % relative humidity at 37 ºC (99 ºF) for a minimum of 8 h, each lidar device or lidar system shall continue to meet the speed accuracy requirements of §2.11.

2.8 Low Supply Voltage Indicator

Each lidar device shall have a low-voltage indicator that alerts the operator either visually or audibly when the supply voltage is reduced below threshold. For a device intended to operate from a nominal 12 V automotive system, this indicator shall activate if the supply voltage is reduced to 10.8 V, or to the lowest voltage specified by the manufacturer (§2.2.5), whichever is lower. For devices utilizing a battery pack, this indicator shall activate if the supply voltage is reduced to the lowest operating voltage specified by the manufacturer (§2.2.5). When tested according to §5.8, the lidar unit shall not display any erroneous readings or below, the threshold voltage that activates the indicator. A blank display is not an erroneous reading.

2.9 Supply Voltage Tolerance

The requirements of this section shall be satisfied when the lidar device is tested in accordance with §5.9. For a device intended to operate from a nominal 12 V automotive system, the requirements shall be met if the voltage is raised 20 % above the standard supply voltage (§3.1.3), or to the manufacturer's specified limit if higher, and when lowered 20 % below the standard supply voltage or to the manufacturer's specified lower voltage limit, if lower. For devices utilizing a battery pack, the requirements shall be met if the voltage is raised to the manufacturer's specified upper limit and reduced to the manufacturer’s specified lower limit (§2.2.5).

2.9.1 Pulse Repetition Rate. The pulse repetition rate shall not vary by more than 0.1 % from its value at the standard supply voltage.

2.9.2 Range and Speed. The UUT shall interact with the simulator at various range and speed settings and continue to meet the speed accuracy requirements of §2.11.

2.10 Speed Display

The speed display characteristics listed below shall be tested in accordance with §5.10 and shall meet the following requirements:

2.10.1 Display Readability. The display shall be clearly readable when tested in accordance with §5.10.1 and used as intended by the manufacturer.

2.10.2 Speed-Display Lock. The lidar unit may include a means to lock a vehicle's speed in the display. The speed-display lock function shall require manual actuation by the lidar operator and shall not be capable of automatic self-lock. The lidar unit shall not recall a previous speed reading when the speed-display-lock function is activated (§5.10.2).

2.10.3 Display-Clear Function. When the lidar unit is activated to begin a new measurement, the display shall be cleared of any previous reading (§5.10.3).

2.10.4 Internal-Circuit-Test Function. The lidar device shall have a self-test function that, when activated, determines if the internal signals will be processed and displayed to within ±2 km/h (±1 mph). The lidar device shall display the correct reading(s) when performing the internal circuit test function, or the lidar device shall display an error message at the end of the test if the test function fails. It shall not be possible for the lidar device to lock in speeds displayed by this test. The internal circuit test switch shall not be labeled cal or calibrate.

2.10.5 Low- and High-speed Display Limits

2.10.5.1 Low Speed. The lidar unit shall function as specified in test procedure §5.10.5 at a speed of 16 km/h (10 mph) or the lowest speed at which the manufacturer states that the device will operate properly, whichever is lower.

2.10.5.2 High Speed. The lidar unit shall function as specified in test procedure §5.10.5 at a speed of 320 km/h (200 mph) or the highest speed at which the manufacturer states that the device will operate properly, whichever is higher.

2.10.6 Audio Tones and Error Messages. If the lidar unit emits audio tones which vary under conditions of valid and invalid data, then the relationship of the sounds to the displayed reading shall be consistent (§5.10.6).

2.10.7 Speed Monitor Alert. The lidar device shall not have a speed-monitoring alert capability (§5.10.7).

2.11 Speed Accuracy: Laboratory Simulation

For simulated speeds of 16 km/h to 320 km/h (10 mph to 200 mph), each lidar unit shall display the speed to within +2 km/h, -3 km/h (+1 mph, -2 mph). For speed accuracy requirements for field operation, see §2.15.

2.11.1 Smoothly Moving Target. When tested on the simulator in accordance with §5.11.1 at twenty or more combinations of speed and distance which are within its working range, the lidar unit shall give no erroneous speed readings. A blank display is not in itself an erroneous reading, but trials that give a blank display or an error message shall be repeated, and the unit shall ultimately give an accurate speed reading at every setting tried. There is no requirement on the range reading in this test.

2.11.2 Smoothly Moving Target with Sawtooth Perturbation. The simulator permits a periodic perturbation in distance to be added to the simulation of a smoothly moving target. When tested on the simulator in accordance with §5.11.2, using a perturbation with an approximate sawtooth shape having a period of about 200 ms and a peak-to-peak amplitude corresponding to a distance of about 1.5 m (5 ft), the lidar unit shall give no erroneous speed readings. A blank display is not an erroneous reading.

2.12 Auxiliary Equipment and Interface

Auxiliary equipment needed for testing shall be present and working.

2.12.1 Output Port. An output port is not required. If a model has an output port, and the port is claimed to be of a standard type such as RS-232, then the manufacturer shall certify that the port indeed meets that standard as commonly interpreted. When connected to a personal computer, using the cabling and software supplied by the manufacturer, the output port shall transmit data in the manner claimed by the owner's manual (§5.12.1).

2.12.2 Switching Output. Some units may have a switching output, which can be used to trigger a camera, for instance. If a unit is claimed to have such an output, then it shall function as stated in the owner's manual when tested using the indicator box as described in §5.12.2.

2.12.3 Remote Control. A remote control or remote trigger is not required. If a model has a connector for remote control that is claimed to be of a standard type such as RS-232, the manufacturer shall certify that the port indeed meets that standard as commonly interpreted. When tested using the cabling and software supplied by the manufacturer, the remote control shall function as stated in the owner's manual. If more complicated proprietary remote control software is needed to fully exercise the remote control function, the lidar unit shall also function as claimed when additional features are tested with that software (§5.12.3).

2.12.4 Remote Trigger. If a remote trigger is supplied in lieu of or in addition to a remote control port, the lidar unit shall be triggered reliably using the switch box supplied by the manufacturer. Also the operation of the switch box shall meet the requirements specified in the owner's manual (§5.12.4).

2.13 Conducted Electromagnetic Interference

The susceptibility of the lidar device to conducted electromagnetic interference (EMI) from the vehicle alternator, vehicle ignition, air conditioner/heater motor, windshield wiper motor and typical police and citizens band transceivers shall be tested in accordance with §5.13. A lidar device powered by a battery pack and designed to also accept a nominal 12 V automotive system and adaptor as an optional source of power, shall also be tested for susceptibility to EMI (§5.13.1 through §5.13.4) utilizing this adaptor. During these tests, a blank target speed display shall not be considered an erroneous reading. Each lidar unit, when tested in accordance with §5.13, shall meet the following requirements:

2.13.1 Simulated Vehicle Alternator Interference. When subjected to a pulse signal 10 μs to 20 μs wide and 1 V peak to peak (p-p) amplitude (except for transition spikes) having maximum rise and fall times of 2 μs (both excluding ringing), a ringing time no greater than 8 μs, and a PRR between 200 pulses per second (pps) and 10,000 pps, the lidar unit shall not display any erroneous readings (§5.13.1).

2.13.2 Simulated Vehicle Ignition, Air Conditioner/Heater Motor, and Windshield Wiper Motor Interference. When subjected to a negative-ramp sawtooth signal having a 1 V p-p amplitude with a positive rise time back to zero of not more than 2 μs, and having a frequency range of 200 Hz to 10 kHz, the lidar unit shall not display any erroneous speed readings (§5.13.2).

2.13.3 Simulated Police FM Transceiver Interference. When subjected to a 10 mW frequency modulated (FM) radio frequency signal in each police radio band, the lidar unit shall not display any erroneous speed readings (§5.13.3).

2.13.4 Simulated Citizen Band (CB) AM Transceiver Interference. When subjected to a 5 mW, amplitude modulated (AM) radio frequency in any of the CB channels specified in §5.13.4, the lidar unit shall not display any erroneous speed readings.

2.14 Radiated Electromagnetic Interference

The susceptibility of a lidar device to electromagnetic radiation from police FM or citizens band AM transceivers shall be subjected to field tests in accordance with §5.14. During these tests, a blank target speed display is not an erroneous reading. Each lidar device shall meet the following requirements:

2.14.1 Police FM Transceiver Interference. This test requires a police FM radio transceiver properly installed in a patrol vehicle. When tested in accordance with §5.14.1, the UUT shall display no erroneous readings when either the installed transceiver or a hand held police FM transceiver with integral antenna is operated within two meters of it.

2.14.2 Citizens Band (CB) AM Transceiver Interference. This test requires a CB AM transceiver properly installed in a patrol vehicle. When tested in accordance with §5.14.2, the UUT shall not display any erroneous readings when the AM radio is transmitting high frequency audio within two meters of it.

2.15 Speed Accuracy: Field Operation

When tested in accordance with §5.15, the lidar UUT must display the speed of a target vehicle within +2, -3 km/h (+1, -2 mph).

2.16 Vehicle Determination (Lidar Systems Only): Field Operation

Speeding violations shall be documented with a recorded image (or images) displaying the target vehicle in an appropriate position defined by the lidar system manufacturer. If the lidar system is used in unattended operation, the evidential image must show at a minimum, the target vehicle’s license plate, speed, location, time, and administrating officer’s identification. For comparison purposes, the manufacturer shall provide sample images.

2.16.1 Attended Operation. The ability of the lidar system to discriminate between target vehicles shall be demonstrated using the field-test methods described in §5.16.1.

2.16.2 Unattended Operation. If the lidar system is to be considered for unattended operation, the manufacturer of the system shall provide a secondary method for verifying that the evidential recorded image properly identifies the target vehicle and reflects this vehicle’s true speed, as described in §5.16.2.