Aspects of the disclosure provide for generation of trajectories for a vehicle driving in an autonomous driving mode. For instance, information identifying a plurality of objects in the vehicle's environment and a confidence value for each of the objects is received. A set of constraints may be generated. That one or more processors are unable to solve for a trajectory given the set of constraints and an acceptable braking limit may be determined. A first constraint is identified as a constraint for which could not be solved and a first confidence value. That the vehicle should apply a maximum braking level is determined based on the identified first confidence value, a threshold, and the determination that the one or more processors are unable to solve for a trajectory. Based on the determination that the vehicle should apply the maximum braking level, the maximum braking level is applied.

A system and method for detecting brake judder in a vehicle may include storing information related to determining whether judder was generated when a vehicle was braked, and facilitating easy recognition of a vehicle in which judder was generated, on the basis of stored information without performing methods such as a separate driving reproduction test and a disc thickness measurement test when maintaining later.

A comfort-based self-driving planning method, including the steps of: a) establishing a relationship model of vibration road surface quality and driving comfort on the basis of a vehicle type; b) obtaining road ahead condition parameters, including abnormal condition information, road flatness and road surface anti-slide performance; c) obtaining the road ahead condition parameters, and adjusting a vehicle expected driving trajectory; d) respectively designing vehicle acceleration, deceleration and constant speed processes, and generating a speed change curve; e) optimising the speed change curve. By means of changeable road surface quality and vehicle vibration action mechanism analysis and image-based road surface anti-slide coefficient evaluation technology, a GIS and vehicle-road communication technology are used to acquire road condition parameters, and vehicle acceleration, deceleration and constant speed processes are respectively designed on the basis of changes in the parameters.

Vehicle control system comprising: a smart cell that is capable of storing and transmitting information on the state of the road surface a control module comprised in a vehicle
and the control module of the vehicle modifying the operating parameters of said vehicle based on the information transmitted by the smart cell.

A road surface condition estimation apparatus may output a detection signal corresponding to a magnitude of a vibration of a tire. The road surface condition estimation apparatus may calculate a level of high frequency component of the detection signal in a contact section. The road surface condition estimation apparatus may transmit a calculation result of the level of high frequency component as road surface condition data each time the tire rotates for a predetermined number of times. The road surface condition estimation apparatus may estimate a condition of road surface based on the road surface condition data. The road surface condition estimation apparatus may stop transmitting the road surface condition data when estimating that the vehicle accelerates or decelerates.

A method for ascertaining the instantaneous roadway roughness in a vehicle. In the method, the frequency-dependent amplitude response is determined from the wheel speed, and a roughness characteristic variable is ascertained as a measure of the roadway roughness.

An exemplary method for performing a brake pad life determination includes providing a brake assembly, including a brake pad position sensor, providing a control system comprising a controller electronically connected to the brake assembly, receiving sensor position data from the brake pad position sensor, determining whether the sensor position data satisfies a first acceptance criterion, if the sensor position data satisfies the first acceptance criterion, performing statistical analysis of the sensor position data to determine a standard deviation and a mean of the sensor position data, determining whether the sensor position data satisfies a second acceptance criterion, and if the sensor position data satisfies the second acceptance criterion, determining a brake pad life estimate.

Aspects of the disclosure provide for generation of trajectories for a vehicle driving in an autonomous driving mode. For instance, information identifying a plurality of objects in the vehicle's environment and a confidence value for each of the objects is received. A set of constraints may be generated. That one or more processors are unable to solve for a trajectory given the set of constraints and an acceptable braking limit may be determined. A first constraint is identified as a constraint for which could not be solved and a first confidence value. That the vehicle should apply a maximum braking level is determined based on the identified first confidence value, a threshold, and the determination that the one or more processors are unable to solve for a trajectory. Based on the determination that the vehicle should apply the maximum braking level, the maximum braking level is applied.

A vehicle brake control device including a wheel speed acquisition section, a wheel acceleration calculation section, an anti-lock brake control section, a bad road determination section, and a bad road amount setting section. The wheel acceleration calculation section calculates a first wheel acceleration and a second wheel acceleration. The bad road determination section determines that a running road surface is a bad road when the calculated first wheel acceleration is larger than a first boundary line where the first wheel acceleration increases as the second wheel acceleration is larger in an area where the first wheel acceleration is larger than the second wheel acceleration. The bad road amount setting section increases a bad road amount as the calculated first wheel acceleration is larger when it is determined that a running road surface is a bad road.

A vehicle brake control device including a front wheel speed acquisition section, a rear wheel speed acquisition section, a front wheel acceleration calculation section, a rear wheel acceleration calculation section, a front wheel anti-lock brake control section capable of executing an anti-lock brake control for the front wheel, a vehicle acceleration acquisition section, and a bad road determination section configured to determine whether or not a running road surface is a bad road based on the front wheel acceleration or the rear wheel acceleration. The bad road determination section executes a bad road determination by selectively using one of the front wheel acceleration and the rear wheel acceleration at least based on information on whether or not the anti-lock brake control for the front wheel is executed and the vehicle acceleration.