ResearchInChina on Automotive Vision Difficulties

ResearchInChina publishes quite a long list of Toyota camera-based Pre-collision System (PCS) difficulties in various situations:

Toyota’s Pre-Collision System (PCS) renders an in-vehicle camera and laser to detect pedestrians and other vehicles in front of the vehicle. If it determines possibility of a frontal collision, the system will prompt the driver to take action and avoid it with audio and visual alerts. If the driver notices the potential collision and apply the brakes, the Pre-Collision System with Pedestrian Detection (PCS w/PD) may apply additional force using Brake Assist (BA). If the driver fails to brake in time, it may automatically apply the brakes to reduce the vehicle’s speed, helping to minimize the likelihood of a frontal collision or reduce its severity.

In some situations (such as the following), a vehicle/pedestrian may not be detected by the radar and camera sensors, thus preventing the system from operating properly:

• When an oncoming vehicle approaches
• When the preceding vehicle is a motorcycle or a bicycle
• When approaching the side or front of a vehicle
• If a preceding vehicle has a small rear end, such as an unloaded truck
• If a preceding vehicle has a low rear end, such as a low bed trailer
• When the preceding vehicle has high ground clearance
• When a preceding vehicle is carrying a load which protrudes past its rear bumper
• If a vehicle ahead is irregularly shaped, such as a tractor or sidecar
• If the sun or other light is shining directly on the vehicle ahead
• If a vehicle cuts in front of your vehicle or emerges from beside a vehicle
• If a preceding vehicle ahead makes an abrupt maneuver (such as sudden swerving, acceleration or deceleration)
• When a sudden cut-in occurs behind a preceding vehicle
• When a preceding vehicle is not right in front of your vehicle
• When driving in bad weather such as heavy rain, fog, snow or a sandstorm
• When the vehicle is hit by water, snow, dust, etc. from a vehicle ahead
• When driving through steam or smoke
• When amount of light changes dramatically, such as at a tunnel exit/entrance
• When a very bright light, such as the sun or the headlights of oncoming vehicle, beat down the camera sensor
• When driving in low light (dusk, dawn, etc.) or when driving without headlights at night or in a tunnel
• After the hybrid system has started and the vehicle has not been driven for a certain period of time
• While making a left/right turn and within a few seconds after making a left/right turn
• While driving on a curve, and within a few seconds after driving on a curve
• If your vehicle is skidding
• If the front of the vehicle is raised or lowered
• If the wheels are misaligned
• If the camera sensor is blocked (by a wiper blade, etc.)
• If your vehicle is wobbling
• If your vehicle is being driven at extremely high speeds
• While driving up or down a slope
• When the camera sensor or radar sensor is misaligned

PCS should be disabled when radar and camera sensor may not recognize a pedestrian in the following circumstances:

• When a pedestrian is 1m or shorter or 2m or taller
• When a pedestrian wears oversized clothing (a rain coat, long skirt, etc.), obscuring the pedestrian’s silhouette
• When a pedestrian carries large baggage, holds an umbrella, etc., hiding part of the body
• When a pedestrian leans forward or squats
• When a pedestrian pushes a pram, wheelchair, bicycle or other vehicle
• When pedestrians are walking in a group or are close together
• When a pedestrian is in white that reflects sunlight and looks extremely bright
• When a pedestrian is in the darkness such as at night or while in a tunnel
• When a pedestrian has clothing with brightness/color similar to scenery and that blend into the background
• When a pedestrian is staying close to or walking alongside a wall, fence, guardrail, vehicle or other obstacle
• When a pedestrian is walking on top of metal on the road surface
• When a pedestrian walks fast
• When a pedestrian abruptly changes walking speed
• When a pedestrian runs out from behind a vehicle or a large object
• When a pedestrian is very close to a side (external rearview mirror) of the vehicle

ADAS suppliers and OEMs work together on product and technology development to make breakthroughs in so many inapplicable scenarios, so that ADAS can get improved and become safer. All players still have a long way to go before autonomous driving comes true.