Friday, August 16, 2013

Safety & Driver Aids in the new Infiniti Q50 Deluxe Technology Package

Back in college and also at work, I often have to write whitepapers that summarize and explain a specific topic or concept. The objective is usually simple - explain some complex technical aspect in simpler terminology and relate it to real life. In the same spirit is something that I have actually enjoyed researching and writing about as it combined my two passions - automobiles and complex computational systems.

The recently released 2014 Infiniti Q50 comes with some very high-tech systems that aid the driver in maintaining safety while driving. One might even say that it is an evolutionary (not revolutionary as these concepts have existed for a while) step closer towards "self-driving vehicles" (save the Google Car). By using multiple analog sensors., interlinking various vehicle systems, performing complex computations in fractions of a second, and controlling the main driving systems, the computers on the Q50 are able to produce the best recourse in order to avoid an accident, which is always better than protection in an accident, which is also important.

The manuals are rather complicated and disjointed, therefore I have tried to simplify and organize the information as best I can. If I have made some errors in my understanding I welcome clarification on any topic.

Let's examine the systems that Infiniti (& Nissan) have had standard on most vehicles until today:

Standard Safety Features
  • Seat Belts - DOT compliant 3-point seat belts with locking both Emergency Locking Retractors (ELR) and Automatic Locking Retractors (ALR). ELR locks the seat-belt when retracted with sudden force e.g if you jerk forward suddenly.. ALR locks the seat-belt when fully extended and ratchets it back in a locked state , for example when attaching a car seat. The system also has an operation monitor (belted vs. unbelted) monitor and occupant & weight classification sensors for the front passenger seat to control the air bag operation. With no passenger or under 40lb passenger and the front passenger airbag will not go off.
  • Seat Belt Pre-Tensioners - A system that under certain types of crashes, rapidly locks the seat belt via a pyrotechnic or explosive device similar to an airbag explosion. This happens much quicker than an ELR system. This safety system also uses a load limiter to release the tension of the seat belt so that it reduces the force of the seatbelt against the chest.
  • Front, Side and Curtain Air Bags - Located in steering wheel, above glove box for passenger, in the sides of both the front seats, along the roof line above the windows for the front and rear passengers. These inflate in a fraction of a second via explosive devices to avoid contact of the persons head and body with vehicle parts. Amount of airbags inflation is dependent and relative to the force of the impact.
  • Anti-Lock Brake System - ABS uses sensors in wheels (when traveling over 3mph) to ensure that a wheel does not lock under hard braking or slippery conditions. It pulsates the brakes, faster than a human foot can,  to avoid locking wheels and avoiding the vehicle from sliding.
  • Vehicle Dynamic Control - VDC uses sensors to monitor driver input of steering and power compared to vehicle motion. It controls the brake pressure and cuts engine power output to avoid sliding and spinning of the vehicle. The VDC can be manually turn off by a button in the cockpit if wheel spin is needed to get the vehicle unstuck from mud or ice by spinning the wheels.
  • Brake Force Distribution -  When braking in a corner, this system redistributes the brake force independently to each of the four wheels based on the tightness of the turn and the load on each wheel to ensure even braking force is applied and vehicle does not lose traction.
  • Hill Start Assist - This system automatically applied the brakes when the vehicle is stopped on hill to avoid rolling backwards for the time it takes the driver to lift off the brake pedal and apply force on the accelerator pedal. The system only works for 2 seconds.

On All Wheel Drive (AWD) models, the Infiniti ATESSA E-TS AWD system automatically moves power from the rear wheels to the front wheels in 1/10th of a second to avoid loss of traction in the rear. It monitors the sensors (ABS, VSC, etc) 10 times every second. This system normally operates at 98% rear, 2% front drive power and can go up to 50% front and 50% rear in a 1/10th of a second. In "Snow Mode" all the systems (VDC, ABC, AWD) are on "higher alert" for more aggressive correction. Additionally, the accelerator and brake pedal inputs are softened in SNOW mode such that the applying the same amount of force to those pedals results in less engine power and braking force respectively to avoid loss of traction and control in ice and snow conditions.

Hybrid Models feature the Approaching Vehicle Sound for Pedestrians (VSP) system. The VSP system uses a speaker mounted in the front grill to simulate the humming sound of a engine (not an exhaust sound), when the hybrid Q50 is fully driven by the Hybrid Battery system and the engine is not running, but the vehicle is accelerating (or decelerating) between 0 and 19mph. This system audibly alerts pedestrians to the presence of a vehicle. Likewise, a reverse beeping sound is produced when backing up the Q50. The VSP can be turned off by a button in the cockpit next to the VDC off button ( Yet to find it?). Here is a video of the backup beep and VSP as the Q50 was on 100% electric power (turn the volume up).

By Adding the Deluxe Technology Package ($5000 MSRP) the vehicle gains some "higher brain functions" and introduces some warning and intervention systems to prevent accidents.  While this package adds a few luxury features as well. We will focus on the following:
  • Front-seat Pre-Crash Seat Belts
  • Backup Collision Intervention (BCI)
  • Blind Spot Warning (BSW) and Blind Spot Intervention (BSI) System
  • Predictive Forward Collision Warning (PSFW)
  • Forward Emergency Braking (FEB)
  • Lane Departure Warning (LDW) and Lane Departure Prevention (LDP) System with Active Lane Control
Window Sticker Snip
The working of all these system together is generally called the Automatic Driver Assistance System - ADAS (also known as the DAS) and is activated by the button on the right on the steering wheel which is called the Dynamic Driver Assistance Switch also known as the Integral Switch or the Intelligent Cruise Control  (ICC) Switch located on the steering wheel on the right side.
DDA Switch/Integral Switch/ICC Switch
This button activates the entire system and individual systems can be turned on and off for a specific User Profile from the InTouch "Driver Assistance" Setting Menu.  The display icon in the driver information panel between the gauges changes from grey to green to designate the ADAS is on and also indicates which systems are active.  Likewise the Intelligent Cruise Control (ICC) is turned on by the same button. 

Very basically the Q50 has 2 types of systems function:
  1. Warning Systems - These warn the driver of imminent danger but do not take any corrective action. These are all ON by default and can be individually turned off from the InTouch Settings Menu
All Warning Systems Active - Grey
  1. Intervention (or Aid) Systems - These perform a corrective action such as reducing acceleration, applying braking or changing steering angle to avoid the accident. Intervention systems need to be turned ON by pressing the Integral Switch on the steering wheel. Again by default all Intervention systems are enabled in the Infiniti InTouch, but are not ACTIVE. and each individual system cane be disabled through the InTouch menu.
All Intervention Systems ON
If there is a problem with the system, then the icons change to a Yellow or Red to designate an issue with a specific system, as well as a specific cluster gauge light is activated.

Since the Q50 supports Driver/User Profile Login, these systems can be customized for each driver.

Infiniti InTouch Driver Assistance Systems
Before we explore the systems,  lets make a note of all the sensor inputs and outputs that the Q50's ADAS has to its disposal to gather data and make the decisions and finally is able to perform some corrective actions. These are the eyes and ears of the system.

  • Front Mounted ICC Sensor - Behind the front bumper is located a Millimeter Wave (same as the TSA uses) and Radar detector. The function of this unit is to detect a vehicle in front of the Q50. It uses the radar to detect the relative speed and distance of the vehicle in front.
  • Lane Camera Unit - This is mounted above the rear view mirror. The function of this camera is to detect lane markers.
  • Side Radar - Installed in the rear bumper on either side, this unit detects other vehicles besides the Q50 in the adjustment lane or when backing up. The radar detects vehicles up to ~50ft away.
  • Front & Rear Sonar - The front and rear bumper are mounted with 4 sonar detectors each, these detect obstacles up to ~5ft away.
  • Blind Spot Warning Lights - lights located on the inside of each side view mirror that lights up orange.
  • Buzzer - Behind the dashboard that beeps to warn the driver
  • Output on Screens - Various lights on the instrument panel, icons, messages, and sounds.
Front Sensors
Rear Sensors
Right Side Blind Spot Warning Light
These systems feed in and out information to the ADAS unit, which is located in the trunk. Combined with the inputs from the BCM, ABS, and TCM, the ADAS can control the brake system, accelerator system, steering, warnings, displays. and buzzers. These are the basis of all the control systems in the Q50. 

Everything else is very smart programming logic written in microcode to perform actions. One universal commonality across all systems is that if a sensor cannot perform an accurate measurement or is obstructed the system is simply disabled as a caution the driver is warned. Likewise under extreme conditions where the driver is purposely performing input, such as high speed cornering or acceleration. sudden movements of the steering wheel or TCS/ABS warning or SNOW mode, most of these systems simply back off as they expect the driver to be "smarter" about the conditions. 

Let's explore the  individual systems as listed in order on the window sticker:

1. Pre-Crash Seat Belt System

This system replaces the standard Seatbelt Pre-Tensioners mentioned above. This system integrates a control unit and motor in both the drivers and passengers seat belt retractors. The systems senses the force of braking, any emergency braking when moving over 9 mph, ABS operation for more than 2 sec, emergency steering turning (90 degrees or more over 36mph) and lateral slipping while turning (more than 19mph). The motor in the seatbelt tightens the seat belts and prevents the occupant from moving around in the seats. If the airbag is deployed, then the pre-crash seat belt system reduces the impact. The caution is that continuous and repeated operation in a short period may overheat the system and cause it to malfunction.
When the seat belt is unfastened, the motor also retracts the seatbelt to provide ease and comfort to getting out of the Q50.

2. Backup Collision Intervention (BCI) System

The backup collision Intervention system helps the driver when other vehicles approach the rear of the Q50 during backing out of a parking spot. This system uses the 4 sonar detectors mounted on the rear bumper in addition to the left and right rear side radar systems.  The BCI operates when the Q50 is below 5mph and in reverse. 

The sonar detects obstacles that are up to 5 ft away from the car. The sonar detection results in a beeping sound that is heard from the appropriate speaker (left, right, front or rear). The beeping sound gets louder as the object is closer and turns to a solid beep when the object is less than 1 ft away. The sonar also works when pulling forward into a parking spot, as there are detectors on the front bumper.

The radar system on the other hand detects vehicles that the driver may not see coming down the parking lot isle on either side of the Q50's blind spots.  The radar can detect vehicles up to 50 ft away and perpendicular to the Q50.
When the radar detects a vehicle approaching, the BCI system first gives a warning by
  1. making a single beep sound
  2. illuminating the blind spot warning light on the side from which the vehicle is approaching
  3. flashing the frame around the rear view monitor with yellow color
If the vehicle approaches closer, and the driver in the Q50 does not stop backing up then the BCI system:
  1. makes 3 beeping sounds
  2. continues to illuminate the blind spot warning light
  3. the frame around the rear view monitor flashes with a red color
  4. pushes the accelerator pedal up and depressed the brakes to stop the Q50.
The BCI system is always ON when the Q50 is turned on. It can be turned off two actions:

   A. Temporarily - By pressing on the Icon in the upper display that is showing the picture of the backup and 360 degree camera. Putting the Q50 in reverse again will reactive the BCI system 

BCI Temporary OFF Button
   B. Permanently - Using the InTouch Setting Menu, Under the Camera/Sonar Settings.

The BCI operation setting  can be tied to a specific Driver Profile and in the theme of warning & Intervention - the warning are the various beeps and lights, the intervention is the stopping of the entire vehicle.

The BCI may not work when the car coming down the isle is too fast (>15mph), small ojects such as people, bikes, etc, when the car is parked at an angle that the radar cannot "see" down the isles. Parked next to bigger vehicles that bock the radar.

3. Blind Spot Warning (BSW) System

The BSW system helps alert the driver of other vehicles in adjacent lanes. The BSW system uses the side radar installed in the rear bumper. The radar can detect vehicles up to 10ft away and operates above when the Q50 is moving at 20mph or above. When the BSW system detects a vehicle in the zone, BSW system illuminates the Blind Spot Warning light located on each side view mirror.

No sound is produced, but is the driver activates the turn signal, then a buzzer sounds twice and the BSW indicator light flashes to warn the driver that a vehicle is in the blind spot area.

If another vehicles comes into the blind spot after the Q50 driver has already turned on the turn signal, then only the BSW light is illuminated and no sound is produced.

BSW & BCI ON/OFF Selection
4. Blind Spot Intervention (BSI) System

The BSI system not only alerts the Q50 driver via the BSW system above, but performs corrective action to avoid an accident that could be potentially caused with a vehicle in the blind spot. The main difference being Intervention vs. Warning. The BSI works when the Q50 is above 37mph.
When a vehicle is detected in the blind spot,  and the BSW light is illuminated on the side view mirror if the Q50 begins to move into the lane of the other vehicle, then the BSI system activates the buzzer 3 times and flashes the BSW blinker, finally BSI applies corrective steering wheel action to keep the Q50 in its lane.

The BSI system only works when the the Dynamic Driver Assistance Switch is activated (green) and the BSI is turned ON through the InTouch System.

The BSI system will not work when brake pedal is being depressed, during acceleration, quick steering movements, hazard flashers are operating, driving on a high speed curve, VDC or ABS are active and in SNOW mode. If any jams or obstructions are present on the radar or camera are present.

Before I explore the the next couple of systems, we need to understand one system which is not listed on the window sticker, but is integral to the working of the next 2 systems. This is called the the Distance Control Assist or DCA. 

Distance Control Assist (DCA) System

 The DCA system uses the ICC's millimeter wave and radar emitters & detectors mounted in the front bumper to measure the speed and distance of the vehicle in front of the Q50 (this is important to note). It communicates with the central ADAS system and in conjunction with the various other systems (such as braking & acceleration feedback) it controls the distance of the Q50 from the vehicle in front.
DCA ON/OFF Selection
It is Active and turned ON, when:
1. the DCA system is ON in the In Touch Driver Assist Settings menu, and
2. the Dynamic Driver Assistance Switch on the steering wheel is ACTIVE (green), and
3. the Q50 is moving above 3mph, and 
4. a vehicle ahead is detected, and 
5. ICC is NOT turned ON or being used, and 
6. the brake pedal is not being depressed.

When a vehicle is detected in front, a small vehicle indicator appears in the Driver information display between the gauge cluster. If the Q50 approaches the vehicle ahead, the DCA system applies the brakes for a smooth deceleration (up to 40% of full braking force) and can bring the Q50 to a completely stop. If the driver is pressing the accelerator, the DCA pushes up the accelerator to assist the driver. When a standstill is reached, the system will chime for the driver to take over brake control. The DCA resumes operations after the vehicle reaches back to 3mph.

Vehicle Ahead Detected
When driver braking is required, the DCA system alerts the driver via a chime and blinking the indicator light.  If the driver continues to press the accelerator pedal further and ignores the DCA warning, the system will cancel its operations and not control the acceleration and braking. 

The DCA does not work when the brakes are applied, ICC is set ON, when VDC or ABS are activated, VDC is manually OFF, car is put into SNOW mode, of the sensors in the front grill become dirty or blocked.

The DCA system can be turned OFF via the Driver Assist Settings Menu in the InTouch system. This disables the Intervention of lowing down Q50, but will not turn off the warning.

5. Predictive Forward Collision Warning (PFCW)

The PFCW uses the same systems as DCA to warn the driver that a 2nd vehicle in front of the Q50 maybe emergency braking. This means that the vehicle in front of the vehicle in front of the Q50 is monitored for emergency braking.
The system operates when the Q50 is moving above 3mph.

The PFCW cannot be individually turned OFF.  Even in the above diagram with DCA turned OFF, the PFCW is still ON as long as the Forward area of the graphic is "white" and a "speaker" is displayed for the Forward Warning (as in the picture above)

Turning off Forward Emergency Braking through the InTouch Driver Assist Setting menu Turns off both PFCW and FEB (below).

PFCW & FEB ON/OFF Option  
6. Forward Emergency Braking (FEB) System 

The FEB system uses ICC to get its information, just like DCA and PFCW. When the distance between the Q50 and the vehicle in front get very small the PFCW operates. If the FEB system determines that a collision is imminent, then a high pitch warning emanates from the buzzer, the accelerator pedal is moved upward and the brake is applied, the brake pressure becomes progressively harder to avoid a collision. The FEB warning light illuminates in the gauge cluster (A Warning triangle) as harder braking is applied.  The FEB also flashes the 2 icons shown (Q50 and front car).

What FEB Warning would look like
The FEB can bring the Q50 to a complete stop. It will hold the brakes for 2 seconds after which the driver needs to apply the brakes. The system will beep to alert the driver.

When a completely stopped vehicle is encountered by the FEB only works at Q50 speeds up to 45mph. Any faster and the FEB may not be able to perform a complete stop.

The FEB is turn on or off through the Driver Assist in the InTouch Menu. To be active the FEB must be enabled in the InTouch Menu, the Q50 is moving at least 3mph and moving 3mph faster than the vehicle in front. The FEB system does not have to be turned on by using the Integral/ICC button.

The FEB & PFCW are both turned on and off by the same function. When OFF this is displayed. 

Infiniti must believe that the PFCW and FEB are critical enough to not have to be manually activated, as deactivating them results in the displaying of a unique cluster warning lamp.
The PFCW and FEB are active even when the Driver Assistance if OFF (grey not green)

The FEB system does not get enabled if the sensors are unable to detect a vehicle properly, for non-vehicles such as animals, motorcycles, obstacles and pedestrians. If the sensors is dirty with snow, ice or dirt, when the accelerator pedal is depressed, or sharp steering input is provided or driving on steep hills of sharp curves.

7. Lane Departure Warning (LDW) System

The LDW system provides a warning when the Q50 is moving over 45mph and starts to leave the current lane without use of turn signal. So start using your turn signals, people!  When the Q50 approaches either side of the lane marker, the warning be be sounded and LDW system will display on the combination meter display.
LDW & LDP, & Active Lane Control System Control
The lane camera monitors the lane markers and inform the ADAS which produces the warnings. The system works as long it is enabled in the InTouch Settings menu and the Q50 is traveling over 45mph and the turn signal has not been operated for more than 2 seconds.
The LDW ignores the side of the car that the turn signal is active for.
The LDW can be Set to be ON or OFF in the InTouch setting and can be tied to a specific driver profile. The LDW on is denoted by a Grey Lines around the Q50 icon in the cluster display.

8. Lane Departure Prevention (LDP) System

The LDP system provides intervention by performing corrective action to keep the Q50 in the proper lane. The LDP system is turned on via the Integral Switch on the steering wheel. Once the LDW has performed a warning, the LDP system calculates the steering angle necessary to perform the corrective action and the sends the information to the direct adaptive steering system (drive by wire system) which performs the corrective action. The Q50 must be moving at least 45mph and the turn signal needs to have been off for more than 3 seconds before the LDP can perform any operations.

If the Lane Camera temperature is too high due to the Q50 being parked in the sun or the windshield is dirty, the LDW & LDP system will not work and warn the user of the system being off.

LDW/LDP many not work on road with faded or multiple lane markers, temporary or construction lane markers, lane covered with water, dirty of snow, sharp curves, sharp contrasting and shiny surfaces. If the headlights are not bright enough due to being dirty, sudden change in brightness, in tunnels and under bridges.

9. Active Lane Control (ALC) System

ALC system improves the straight line travel of the Q50 so that the driver is able to keep the car straight with fewer steering wheel corrections. ALC measure the front tire angles, the steering wheel torque to reduce the Q50's drift in a lane. This drift maybe caused by a strong side wind or sloping of the lane away from a center.

ALC Description
The ALC is controlled by the chassis control module. The lane camera unit monitors the lane markers and sends the signal to the chassis control unit, the chassis control unit measure the difference between the expected vehicle movement travel and actual travel, the information is sent to the the direct adaptive steering wheel system and it performs the corrective action. When the ALC is performing corrective action the the icon on the driver display between the gages is illuminated.

The ALC system only operates when the LDP system is also set to ON. The ALC system can be set ON/OFF in the InTouch system. Using the  Integral switch the ALC can be set to a low or high setting for ALC sensitivity. The Q50 must be moving at least 45mph and the turn signal must be have been off for more than 3 seconds. ALC does not operate when LDP is off, speed is less than 45mph, side markers are lost on a curving road, sudden steering input, when ABS, TCS and VDC are activated. If the camera is obstructed or the Q50's interior temperature is very high the ALC system will not operate. Also if the lane condition are not ideal, i.e. faded lane markers, temporary lane markers, snow, ice, sudden brightness changes, etc.

Additionally, key related system worth mentioning:

10. Intelligent Cruise Control (ICC) System

The ICC system automatically maintains a selected distance from the vehicle ahead and automatically slows down or speed up the Q50 up to the pre-set cruise speed without driver input to the accelerator or brakes. The ICC system operates between 20-90 MPH and allows the user to select both the cruising speed and the distance (short, medium and long) between the vehicles.  The system can also bring the Q50 to a complete stop, but requires the driver to step on the brakes after that. If the vehicle ahead comes to a rapid stop, the system will chime and a warning will flash in the Driver Information Display as that activates the Forward Emergency Braking.

Regular Cruise Control can be invoked by depressing and holding the ICC button for 1.5 seconds.

The system is cancelled when: Cancel switch is hit, Brake Pedal is depressed, vehicle ahead is not detected below 15mph, Shift Level is not in "D" or Manual positions, Parking Brake is applied, System determines vehicle is at a standstill, SNOW mode is selected, ABS or VDC Activate, Wheel Slips, VDC is turned OFF, Main Switch is OFF, System detects a malfunction.

ICC is intended for straight, open and dry roads with light traffic. It will be inaccurate in heavy city traffic, sharp curves, snow and icy conditions, heavy rain or fog, when pedestrians and large stationary objects are present on narrow roads, steep uphill and downhill roads.  If a vehicle sudden pulls into the detection zone it may not be detected until it completely moves in front, likewise motorcycles may nat not be detected if they are riding off center, a chime and visual blinking system indicator will indicate such an event.  Going on a curvy road may be inaccurate as oncoming traffic maybe wrongfully detected

I do not intend on testing the PFCW and FEB systems as that could be a costly test. As I have more and better pictures available, I will update this post.


The net of it is that the systems in the Q50 perform excellent warnings and interventions (if selected) so that they can prevent the driver of the Q50 from causing an accident due to a lapse in judgement, or a quick distraction. I do not believe that these systems are a replacement for good driving, if anything the buzzing and beeping should train the Q50 driver to avoid these from ever happening.  I like the conservative approach that Infiniti took in making these systems non-intrusive and that the user has to click a button to ask the system to intervene. Any malfunction or blockage of a sensors, basically disables the system, which means it is only allowed to make good decision and not "maybe" decisions. The Q50 is indeed a huge evolutionary step forward and hopefully what the majority of the automative industry will start adopting. I know that other manufacturers have similar systems, but I especially like the complete packaging that the Q50 has done and the greater possibilities available because of the drive-by-wire system.

The Q50 still does not have turbo boost to go over road blocks,  cannot scan for human vitals, and definitely cannot scan though buildings for armed bad guys. Perhaps the "Deluxe Crime Stopper Package" in the future will add those features.