Handsfree Driving


Handsfree is an adjective describing equipment that can be used without the use of hands (for example via voice commands) or, in a wider sense, equipment which needs only limited use of hands, or for which the controls are positioned so that the hands are able to occupy themselves with another task (such as driving) without needing to hunt far afield for the controls.

Devices that are typically used for handsfree communication use Bluetooth as its wireless technology. They still require a mobile phone or other device to initiate a call. These devices include Bluetooth headsets, hands-free car kits (HFCK), and personal navigation devices (PND). Originally introduced as optional features connected by a wire to mobile phones or other communication devices, they now generally are available with wireless technology.

Bluetooth handsfree options are now also easily found in any high end automotive as part of the vehicle's stereo system, or in after market stereo system units. This option utilizes the vehicle's speakers to transmit the caller's voice in the phone call and have an embedded microphone in the stereo unit itself, the steering wheel, or use a separate wired microphone that can be placed anywhere in the vehicle.

All of us would like to drive our car with a mobile held in one hand, talking to the other person. But we should be careful; we don't know when the car just before us apply the break and everything are gone. A serious problem encountered in most of the cities, National Highways, where any mistake means no 'turning back'! There comes the tomorrows technology; Hand free driven car. Initializing the modern technological approach in Robotics.
What is the need for safety precaution?

All around the world almost 45% of the accidents occur by mistakes of the driver. Most of these accidents are fatal. The victims of such accidents are either severly injured, some even risk their life by their careless driving. This was the main reason behind this project work put forward by the Delphi-Delco electronic systems and General Motors Corporation. It was called the Automotive Collision Avoidance Systems (ACAS) field operation program.

It was aimed at integration of the latest technology Forward Collision Warning (FCW) and Adaptive Cruise Control (ACC). The project has two phases. The Phase I started by June 1999, it lasted for about 27 months and II phase started immediately just after the Phase I and expected to be complete by 32 months.
The phase I include development and integration of ACC and FCW systems on the automotive. The phase II include the deployment fleet on ten cars and field operation test.

Handsfree mobile phones are obligatory in many countries for use of a mobile phone while driving. However, studies have shown that even with a hands-free unit, the added distraction to the driver, and the increase in accident rates, are almost as substantial as when driving and talking on a normal mobile phone.

In a new law, introduced in the United Kingdom in 2003, it is illegal to use a handheld mobile phone while driving. Similar laws have been adopted in many jurisdictions worldwide, and many make provisions for hands-free phone use.

Installation of Hands Free devices in the UK is governed by MPT 1362, which is now referred to as FCS 1362. A technical document created and updated by the Federation of Communcation Services.

In the USA, California, State of Washington, Connecticut, New York, New Jersey & Washington D.C. have banned talking on a hand-held cellphone while driving.

2 laws will take effect on July 1st, 2008 in California thanks to Governor Schwarzenegger:

  1. SENATE BILL 33: Prohibits anyone under the age of 18 from using any wireless telephone or mobile service device while driving, including hands-free devices, walkie-talkies, pagers, two-way messaging devices and laptop computers.
  2. SB 1613: Requires all California motorists to use hands-free devices when using a cell phone while driving.

Forward Collision Warning (FCW) System was one of the achievements of the Delphi-Delco Electronic Systems, which was successfully implemented in the (a) 1994 Toyota Lexus LS400 (b) 1994 GM Cadillac Seville, and (c) 1998 Opel Vectra. These vehicles have been modified to provide the basic functionality of fully integrated ACC and FCW systems. Forewarn Smart Cruise Control with Headway Alert uses a mechanically scanning, 76 GHz, long-range radar sensor to detect objects in the vehicle's path up to 150 meters or 402 feet ahead. The system helps to reduce the need for drivers to manually adjust speed or disengage cruise control when encountering slower traffic.

Adaptive Cruise Control (ACC) and Forward Collision Warning (FCW) systems require an ability to resolve and identify robustly the existence of both stationary and moving 'target' vehicles that are in the motion path of the Host vehicle. The performance of these systems is affected by their ability (a) to estimate the relative inter-vehicular path motion (i.e.: range, relative speed, radius of curvature, etc.) between the host vehicle, the roadway ahead of the host, and all of the appropriate targets (i.e.: roadside objects, and in-lane, adjacent lane, and crossing vehicles, etc.); and (b) to predict the mutual intersection of these motion paths. In addition, these systems must be robust in the presence of various types of driving behavior (e.g.: in-lane weaving/drift, lane change maneuvers, etc.) and roadway conditions (e.g. straight roads, curved roads, curve entry/exit transitions, intersections, etc.) that are encountered in the 'real-world' environment.

The target selection approach pursued used a single active forward looking radar sensor augmented with a yaw rate sensor. The forward-looking radar sensor provided target range, range rate, and angular position information. The yaw rate sensor was used to estimate the roadway curvature ahead of the Host vehicle. Delphi's first generation target discrimination algorithms were used to identify overhead bridge objects and to discriminate between moving cars and trucks. The Target / Host kinematics were evaluated to determine target motion status (i.e.: oncoming, stopped, moving, cut-in and cut-out, etc.), and geometric relationships were employed to determine which of the valid roadway objects fell within the Host's forward projected path. The improved algorithms yielded very good results, but they were prone to false alarms during curve entry/exit scenarios and during host lane changes.

Since handsfree devices replace a phone's own speaker and microphone capability in a phone call, they now also must deal with the same issues that standard mobile phones and land phones deal with. The main acoustic issues are echo cancellation and noise suppression, although there are others as well. There have been many ways developed to cancel echo in phone calls and results range from poor to excellent.

These acoustic technologies must also remove or reduce the noise levels so that the caller is well understood. A person making a call from a handsfree device who is in a busy restaurant or while driving will introduce large levels of noise into the call. This situation is complicated as the software must not only remove the noise around him, but must transmit his voice clearly and loudly to whoever is connected to him.

The best software solutions combine both echo cancellation and noise cancellation into a single technology so that the caller has the freedom to use a handsfree device anywhere they please. Having an acoustic solution with only one feature will dramatically reduce its flexibility.