Abstract:
The present invention is a method and apparatus for providing an enhanced automatic drive-thru experience to the customers in a vehicle by allowing use of natural hand gestures to interact with digital content. The invention is named Virtual Touch Ordering System (VTOS). In the VTOS, the virtual touch interaction is defined to be a contact free interaction, in which a user is able to select graphical objects within the digital contents on a display system and is able to control the processes connected to the graphical objects, by natural hand gestures without touching any physical devices, such as a keyboard or a touch screen. Using the virtual touch interaction of the VTOS, the user is able to complete transactions or ordering, without leaving the car and without any physical contact with the display. A plurality of Computer Vision algorithms in the VTOS processes a plurality of input image sequences from the image-capturing system that is pointed at the customers in a vehicle and performs the virtual touch interaction by natural hand gestures. The invention can increase the throughput of drive-thru interaction and reduce the delay in wait time, labor cost, and maintenance cost.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
   This application is based on and claims priority to U.S. Provisional Application No. 60/415,690, filed Oct. 3, 2002, which is fully incorporated herein by reference. 

   FEDERALLY SPONSORED RESEARCH 
   Not Applicable 
   SEQUENCE LISTING OR PROGRAM 
   Not Applicable 
   BACKGROUND OF THE INVENTION—FIELD OF THE INVENTION 
   The present invention is a method and apparatus for providing an enhanced automatic drive-thru experience to customers in a vehicle with a virtual touch interaction by natural hand gesture with digital information, while efficiently increasing the throughput of the drive-thru interaction and reducing the delay in wait time, labor cost, and maintenance cost. The present invention provides a ‘contact free’ method for performing the virtual touch interaction, by means of an analysis of images from image-capturing sensors, such as video cameras, that are oriented towards the user. 
   BACKGROUND OF THE INVENTION 
   One of the prior arts for the drive-thru system involves one or more people in the store interacting with the driver of the vehicle remotely. This interaction is commonly performed by means of a two-way speaker and microphone, with a window where a person is waiting to attend the user. Inconsistent speed, accuracy and customer experience, which can occur throughout the traditional drive-thru process, pose unique challenges for corporate planners. The length of queue, the appearance of the menu board, delay of initial greeting, speaker clarity, communication between the consumer and the order taker, communication between the order taker and order fulfillment, the payment process, order delivery and accuracy are all critical stages in delivering the customer experience. Miscommunications due to language barriers, speaker or microphone malfunction, or just plain poor attitudes can combine to create a very unpleasant customer experience. Re-engineering of the drive-thru process must take place if they are expected to keep pace with the increasing demand and desires of the general public. 
   This traditional drive-thru system has inherent inefficiency of wait time in the interaction process. In order to solve this problem, some approaches have been attempted. For example, the three-window idea, one window each for ordering, payment, and pick-up, has been widely used in the quick-service restaurant, and it could decrease the inefficiency to some degree. However, this method results in having more attendants with the three windows and relevant building construction cost. This method is also not easily adaptable to the other type of drive-thru interaction process than that of the quick-service restaurant. For example, the drive-thru bank will not need three-windows for its transaction. 
   U.S. Pat. No. 6,026,375 of Hall et al. disclosed a method and apparatus for processing orders from customers in a mobile environment, trying to provide a solution for the inefficiencies of the drive-thru. While they have interesting and versatile approaches to the drive-thru process, the customers in the vehicle need to have mobile access to the network, which could require extra cost and burden to the customer. Unless enough people within the local area have mobile access to the network mentioned in the U.S. Pat. No. 6,026,375 of Hall et al., there is a possibility that the network might not be utilized. Also, signals of mobile access, such as cell phones, weaken, depending upon the location, weather condition, etc. Hence, the reliability of such a system is a question. Finally, since the interface is not natural (i.e., the user has to select from a large menu using the alpha-numeric keypad), there are issues of delay. 
   U.S. Pat. No. 5,168,354 of Martinez et al. disclosed a fast food drive-thru video communication system. While this approach tries to improve the drive-thru interaction using the video communication system in addition to the conventional voice only drive-thru system, allowing the customer to maintain eye-to-eye visual contact with the attendant located within the restaurant, the approach is still not able to solve the delay of interaction problem for the plurality of customers and vehicles. 
   U.S. Pat. No. 4,884,662 of Cho et al. disclosed a method of operating a driver interaction service center with a plurality of collection stations for dispensing services, and a plurality of driveways. While the suggested method increases the throughput of the interaction process, it also results in hiring more attendants or order-takers for each station, thus increasing labor costs. 
   Using the automatic systems, such as a touch screen system or a keypad with a digital display, which is, for example, commonly embodied in automatic teller machines, could reduce the labor costs. However, these systems result in maintenance and hygiene issues since the drivers touch the system physically. The touch-screen display is fixed and, therefore, cannot adapt to the various sizes of vehicles and arm lengths of people. This would be devastating to the fast food drive-thru industry with the increase in order time alone. This also causes difficulty in parking the vehicle, as it needs to be close to the system as possible in order for the driver to be able to touch the screen, stretching the hand to the device. This is ergonomically inappropriate because it is not only uncomfortable to the driver but also could cause damage to the system. If the driver has to step out of the vehicle to use the automatic systems, this will result in more delay and inconvenience to the customer. Other solutions include a device that the user can put inside the vehicle, such as a keypad, or track ball; however, these also involve disadvantages of hygienic issues and durability. 
   The present invention is named Virtual Touch Ordering System (VTOS). The VTOS can overcome the limitations of these prior art drive-thru systems and provide improved automatic drive-thru experience to the customers with convenient interface and digital information while efficiently increasing the throughput of the drive-thru interaction and profitability. The present invention provides a ‘contact free’ method for performing the interaction, by means of an analysis of images from image-capturing sensors, such as video cameras, that are oriented towards the user. 
   Virtually no human labor is necessary in taking orders or making most transactions with the VTOS, since it is a fully automated system. In the case of some transactions where human involvement is indispensable, such as certain kind of bank transaction, the VTOS can reduce the number of attendants greatly, thus reducing overall drive-thru labor costs. Reducing maintenance costs could be one of the big advantages in the VTOS drive-thru system. The nature of virtual touch capability of the VTOS avoids the wear and tear losses of the system, thus reducing the maintenance cost over time. The virtual touch interaction capability also enhances the customer experience by allowing more customized interaction. The VTOS can provide easy to learn graphical user interface for the digital contents. 
   SUMMARY 
   In an exemplary embodiment, the VTOS can be comprised of a housing (enclosure), a plurality of the image-capturing system, a display system, a processing and controlling system, a lighting system, a drive-thru ceiling structure, and a sound system (hidden in the enclosure). The processing and controlling system is connected to the image-capturing system, the display system, and the sound system. The image-capturing system is defined to be a system with plurality of image-capturing devices, such as cameras, frame grabbers and all relevant peripherals, in the VTOS. Lighting system and drive-thru ceiling structure help the VTOS to process the user detection and the contact-free interaction by helping computer vision technology operate more reliably. The lighting system and the drive-thru ceiling structure is not the essential part of the VTOS, but they belong to the VTOS as the environmental set up, in a broader concept. 
   Generally the implementation of the VTOS makes transitions within a series of interaction states, which are listed as follows.
         Wait State.   Interaction Initiation State.   Driver Interaction State.   Interaction Termination State       

   The transition between the different states of the VTOS is summarized as follows. 
   The VTOS is in a default Wait State when there is no driver in the vicinity of the system. When a vehicle approaches and is parked nearby the system and a driver is detected by the face/vehicle detection technology, the Interaction Initiation State starts. At the Interaction Initiation State, the VTOS can display a welcome message or brief introduction about how to use the system. The image-capturing system for hand detection and tracking, either left or right hand, analyzes the driver&#39;s movements and gestures. A plurality of images from the image-capturing system of the VTOS is analyzed by a processing and controlling system to interpret the user&#39;s actions, such as position of the limbs (hand, arm, etc.) and gestures (defined by temporal location of the limbs or particular postures). 
   For the face detection, any robust, reliable, and efficient face detection method can be used. In U.S. Pat. No. 6,184,926 of Khosravi et al. and U.S. Pat. No. 6,404,900 of Qian et al., the authors disclosed methods for human face detection. In M. H. Yang, D. J. Kriegman, and N. Ahuja, “Detecting Faces in Images: A Survey,” IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 24, no. 1, January 2002, the authors describe various approaches for the face detection. In the exemplary embodiment of the invention, a neural network based face detector or SVM based face detection method may be used. H. Rowley, S. Baluja, and T. Kanade, “Neural Network-Based Face Detection,” IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 20, no. 1, pp. 23–38, January 1998, explains about the neural network based face detector in more details. E. Osuna, R. Freund, and F. Girosi, “Training Support Vector Machines: An Application to Face Detection,” Proc. IEEE Conf. Computer Vision and Pattern Recognition, pp. 130–136, 1997 explains about the SVM based face detection approach in more details. 
   The VTOS detects the vehicle and the position of the vehicle window, which is used to define the Maximum Interaction Range Volume and the Optimal Interaction Volume, which is the region in real world 3D space that is tracked and mapped to find the hand location. The maximum interaction range volume and the optimal interaction volume of the VTOS are virtual space, which change according to the physical dimension of the driver and the vehicle. Since the volumes change according to the position of the driver and vehicle, some degree of freedom for the motion is possible. This is helpful and necessary for the contact-free interaction process by the VTOS, because the vehicles can be parked in random position within the vicinity of the VTOS units. 
   The maximum interaction range volume shows the maximum range, in which the driver can interact with the VTOS. The VTOS is able to detect and enable the driver&#39;s hand gesture for the contact-free interaction within this region. However, in most cases, the driver will feel comfortable in interacting with the VTOS within the optimal interaction volume because of the physical limitation in the range of movement a driver can reach with his or her hand. The optimal interaction volume is a sub volume that is located according to the position of the window of the vehicle in the maximum interaction range volume. This volume will preferably be located such that the user can use either the left or the right hand in a natural way. 
   When the driver actually engages with the Driver Interaction State, the VTOS provides the digital content for taking orders or completing transactions through the display system. The user points with his hand to the screen to make selections among the displayed digital content. The design of the digital content widely depends on the owner or designer of the particular embodiment of the VTOS, since the VTOS can be used for any drive-thru interaction, such as taking orders and completing transactions in a drive-thru bank, photo center, and quick service restaurant. Generally the overall content of the VTOS comprises a welcome message, plurality of selection screens and main content, and the exit screen. When the customer points to the display with his or her hand, the VTOS shows a visual feedback on the screen of the display system to the user as to where the system is interpreting the hand location. 
   The contact-free interface can be implemented using any of the reliable real-time gesture recognition technology in the computer vision. One example of the contact-free interface is explained in detail by R. Sharma, N. Krahnstoever, and E. Schapira, “Method and System for Detecting Conscious Hand Movement Patterns and Computer-generated Visual Feedback for Facilitating Human-computer Interaction”, U.S. Provisional Patent 60/369,279, Apr. 2, 2002. 
   When the user finishes the interaction, the VTOS goes into the Interaction Termination State. In this state, the VTOS can display a brief parting message, such as “Thank you. Come again!” message, confirmation message, or any relevant content, which signals to the user the end of the interaction and lets the driver know what to do next as the result of the final interaction, such as displaying “Proceed to the next window!” message or “Be careful when you exit!” message. When the interaction is terminated, the VTOS goes back to the initial Wait State and looks for the next driver. 
   Additional features of the VTOS are summarized as follows. 
   The location and number of the image-capturing system and the location of the display system for the present invention could be in multiple places around the vehicle as long as the driver is able to see the display system and the VTOS can see the driver&#39;s hand motion. The system can track the hand of the user when it is located outside or inside the vehicle, therefore giving the option to the user of interacting with the display without opening the vehicle window. 
   Different types of vehicles could have different heights. Different drivers in the same type of vehicle can also have different heights. In order to make the virtual touch interaction more comfortable and reliable, the VTOS can adjust the height of the display region according to the level of eyesight of the driver using the computer vision technology. Using the eye level, the main content can be positioned in the corresponding level within the display screen. The other parts of the display screen, where the main content is not shown, can be used for advertisement or promotional display. The VTOS also detects if the user is looking at the display, and further instructions can be presented only if the user is looking at the display to ensure the customer&#39;s attention. 
   The VTOS is able to collect data using computer vision algorithms and analyze the results of the ordered items and customer behaviors in selection processes, which can be saved after customers finish the interaction of giving orders and other transactions. 
   The data gathering services utilize computer vision technologies to provide visibility to customer traffic, composition, and behavior. This is explained in detail by R. Sharma and A. Castellano, “Method for augmenting transaction data with visually extracted demographics of people using computer vision”, U.S. Provisional Patent, 60/402,817, Aug. 12, 2002, and by R. Sharma and T. Castellano, “Automatic detection and aggregation of demographics and behavior of people using computer vision”, U.S. Provisional Patent, 60/399,246, Jul. 29, 2002. These services include detection of customers, their classification into segments based on demographics, and the capture of information about their interaction with the VTOS. The exemplary statistics gathered by the VTOS can include;
         the amount of time that is spent to finish the interaction in the drive-thru;   the division of people in demographic groups, including gender, race, broad age group;   the traffic measurement, such as traffic composition by time of day, day of week, and demographic shifts; and the customer behavior, such as the time spent at a particular item selection screen or whether the purchases are made or not.       

   So far a single housing unit model of the VTOS is summarized. However, the VTOS can also comprise multiple housing units, which are organized in pipeline and/or parallel in order to perform multiple transactions at the same time, similar to the schemes of a gas station. Overall, this model increases the throughput of the drive-thru, decreasing the average wait time per customer. For the case of certain transactions, such as the bank transaction, which could specifically require human attendant&#39;s involvement, the design of the VTOS could be modified in a way such as to minimize the number of attendants. 

   
     DRAWINGS—FIGURES 
       FIG. 1  is an overall view of the VTOS. 
       FIG. 2  is an overall view of the VTOS from the top. 
       FIG. 3  is a model of VTOS representing multiple units of the housing, organized in pipeline and parallel in order to perform several transactions at the same time. 
       FIG. 4  is a state diagram of the VTOS, which shows the processes according to the driver interaction. 
       FIG. 5  shows the exemplary Maximum Interaction Range Volume and the exemplary Optimal Interaction Volume of the VTOS. 
       FIG. 6  shows an exemplary method for vehicle detection for the VTOS. 
       FIG. 7  shows that VTOS dynamically changes the digital content display region within the vertically elongated display system using the height detection capability. 
       FIG. 8  shows an exemplary screen shot of the digital content of the VTOS in the context of Quick Service Restaurant. 
       FIG. 9  shows another exemplary screen shot of the digital content of the VTOS in the context of Quick Service Restaurant. 
   

   DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1  shows the overall view of the VTOS. In this particular exemplary embodiment shown in  FIG. 1 , the VTOS consists of a housing (enclosure)  100 , plurality of the image-capturing system  110 , a display system  111 , and a sound system  113  (hidden in the enclosure). The processing and controlling system  112  is connected to these peripheral sub-systems, such as the image-capturing system  110 , the display system  111 , and the sound system  113 , as in the exemplary embodiment shown in  FIG. 2 . The image-capturing system  110  is defined to be a system with plurality of image-capturing devices, such as cameras, frame grabbers and all relevant peripherals, in the VTOS. The processing and controlling system  112  can be installed inside the housing  100  in the exemplary embodiment shown in  FIG. 1 , or it can be installed in a remote place within the restaurant building or any of its surrounding areas, where the system can be securely and efficiently placed. The owner or designer of the particular VTOS can decide how the processing and controlling system  112  is connected with the peripheral sub-systems. If the owner or designer of the particular VTOS chooses to have the conventional vocal drive-thru interaction method as one of the interaction options for the customers, a microphone can be attached to the VTOS. It can be used as one of the input modalities although it will be the secondary interaction modality in the VTOS. As in the exemplary embodiment shown in  FIG. 1 , the VTOS allows the customer inside a vehicle  600  select the items from the main digital content displayed through the display system  111  of the VTOS using the contact-free interface  304  within the interaction volume  430 . Lighting system  117  and drive-thru ceiling structure  601  help the VTOS to process the user detection and the contact-free interaction  304  by helping computer vision technology operate more reliably. The lighting system  117  and the drive-thru ceiling structure  601  is not the essential part of the VTOS, but they belong to the VTOS as the environmental set up, in a broader concept. 
     FIG. 2  is a view of the VTOS and a driver interacting with it, as viewed from the top. As in the exemplary embodiment shown in  FIG. 2 , the apparatus of the invention could comprise the processing and controlling system  112 , a display system  111 , a sound system  113 , and one or more visual sensors, the plurality of the image-capturing system  110 . In this particular embodiment, two image-capturing systems are used for hand detection and tracking, either left or right hand, and one for human face detection and tracking.  FIG. 2  also shows the virtual components of the system, which are the Maximum Interaction Range Volume  431 , and the Optimal Interaction Volume  432 . These volumes are explained in more detail in  FIG. 5 . To use the system more efficiently, it is desirable to have the vehicle  600  parked as close to the display as possible, so that the Maximum interaction range volume  431  contains the range of hand movements in real world coordinates. 
   Once the vehicle  600  is parked in the vicinity of the system, a driver is detected by the face detection technology. For the face detection, any robust, reliable, and efficient face detection method can be used. In U.S. Pat. No. 6,184,926 of Khosravi et al. and U.S. Pat. No. 6,404,900 of Qian et al., the authors disclosed methods for human face detection. In M. H. Yang, D. J. Kriegman, and N. Ahuja, “Detecting Faces in Images: A Survey,” IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 24, no. 1, January 2002, the authors describe various approaches for the face detection. In the exemplary embodiment, a neural network based face detector or SVM based face detection method may be used. H. Rowley, S. Baluja, and T. Kanade, “Neural Network-Based Face Detection,” IEEE Trans. Pattern Analysis and Machine Intelligence, vol. 20, no. 1, pp. 23–38, Jan. 1998, explains about the neural network based face detector in more details. E. Osuna, R. Freund, and F. Girosi, “Training Support Vector Machines: An Application to Face Detection,” Proc. IEEE Conf. Computer Vision and Pattern Recognition, pp. 130–136, 1997 explains about the SVM based face detection approach in more details. 
   At this state, the image-capturing systems  110  for hand detection and tracking analyze the driver&#39;s movements and gestures. The VTOS detects the vehicle  600  and the position of the window, which is used to define the optimal interaction volume  432  that is the region in real world 3D space that is tracked and mapped to find the hand location. Other information obtained from the image-capturing system  110  is the height of the vehicle  600 , which is used to modify the information presented on the display, or the location of the display itself, in order to gain comfort for the user to watch and interact. By means of the image-capturing system  110  for face, the VTOS detects if the user is looking at the display, and consequently starts a short salutation and instruction video. Further instructions can also be presented only if the user is looking at the display. 
   The location and number of the image-capturing systems  110  and the location of the display system  111  for the present invention could be different from those shown in the exemplary embodiment in  FIG. 2 . An alternative location for the display can be in front of the windshield of the vehicle  600 . In this embodiment, the sensors, image-capturing system  110 , could be located in front of the vehicle  600 , and the user can interact from the inside of the vehicle  600  using the contact-free interaction  304  without opening a window. 
   When the customer points to the display with his or her hand, the VTOS shows a visual stimulus on the display screen that provides feedback to the user as to where the system is interpreting the hand location. Then the user can point to region of the screen to select items. For the exemplary embodiment, the selection can be made by pointing to the same location and holding the hand for a predefined period of time (e.g.: 1 second). The display system screen will display a Graphical User Interface (GUI) with selectable areas such as buttons. The contact-free interface allows the user to make selections using the GUI. The contact-free interface can be implemented using any of the reliable real-time gesture recognition technology in the computer vision. The exemplary embodiment of the VTOS shown in  FIG. 2  can use the contact-free interaction  304  method explained in detail by R. Sharma, N. Krahnstoever, and E. Schapira, “Method and System for Detecting Conscious Hand Movement Patterns and Computer-generated Visual Feedback for Facilitating Human-computer Interaction”, U.S. Provisional Patent 60/369,279, Apr. 2, 2002. The content of the screen widely depends on the particular embodiment of the VTOS. 
     FIG. 3  shows another exemplary embodiment of the VTOS. As shown in  FIG. 3 , the VTOS could comprise multiple housing units  100 , which are organized in pipeline and/or parallel in order to perform multiple transactions at the same time, similar to a gas station. This model increases the overall throughput of the drive-thru, decreasing the average wait time per customer. One of the difficulties of having pipelined and parallel drive-thru units in the conventional drive-thru system with voice only interaction was the cost of hiring as many attendants or order takers as the number of the drive-thru interaction units. However, with the exemplary embodiment of the pipelined and parallel model of the VTOS shown in  FIG. 3 , extra cost for hiring more attendants or order takers is not necessary. Virtually, no human labor is needed with the VTOS for taking orders and most transactions. All the orders and transactions can be made by the plurality of the VTOS units  100  and these interaction results are sent to the people in the building, such as the food preparation team of the quick service restaurant, directly through the central server and its results on monitor screen inside the relevant building. 
   For the case of certain transactions, such as the bank transaction, which could specifically require human attendant&#39;s involvement, the design of the VTOS could be modified in a way such as to minimize the number of attendants. For example, a window with human attendant can be dedicated for the specific transaction, which requires human labor, as it is done now in the conventional drive-thru systems, and allow the plurality of the VTOS units to other parts of the drive-thru facility for the automated drive-thru interactions. This will increase the overall throughput of the drive-thru and decrease the average wait time per customer. 
   In the exemplary pipelined and parallel model of the VTOS shown in the  FIG. 3 , the sequence of the final interaction from the plurality of the units could be random. For example, in the exemplary pipelined and parallel model of the VTOS shown in the  FIG. 3 , any one of the 4 drivers in the vehicles  600  interacting with the VTOS units could finish the interaction first. The second, the third, and the fourth final interaction could be from any of the rest of the VTOS units, depending on the particular drivers&#39; interaction behaviors, such as the individuals&#39; various desire for specific items on the selection choices and personal interaction time with the VTOS unit. These random interaction results can be received in a central server according to the timed final interaction sequences and processed in the sequence in which they are received. 
   For this particular model of VTOS, how to proceed to the next window, such as payment and pickup window, from the interaction (ordering) station has to be designed carefully in order to avoid the traffic in the interval between the interaction (ordering) station and the next window, (payment and pickup window). The methods of such control can be varied depending on the setup of the particular restaurant, such as the number of the payment window and the number of the pickup window. For example, when there is a single payment window and a single pickup window, (they could be further combined in one window), the vehicles  600  can be released from the interaction (ordering) station in the order the interactions (orders) are made. For this approach, physical structures, such as light signals attached to the VTOS unit, could be used to signal the vehicle  600  to proceed to the payment and pickup window. The display system  111  of the VTOS could also be used as the traffic controller, by displaying traffic control messages, such as “Please, Wait!” or “Please, Move forward!” When there are multiple payment windows and multiple pickup windows, the vehicles  600  in each pipeline can be released to its own payment window and pickup window, designated to the specific pipeline. However, for this method, additional cost for having multiple windows and food conveyer system might be needed. 
   Overall the exemplary pipelined and parallel model of the VTOS shown in the  FIG. 3  may require more physical space, where the vehicle  600  access to the interaction (ordering) station and out of the interaction (ordering) station should be possible very easily, so that multiple drivers can park their vehicles  600  and interact with the VTOS. However, the maximum interaction range volume  431  and the optimal interaction volume  432  of the VTOS, which will be explained later, allow some degree of freedom to the driver for parking and interaction with the VTOS units. 
     FIG. 4  is a state diagram of the VTOS, which shows the processes according to the driver interaction. The VTOS is in a default Wait State  610  when there is no driver in the vicinity of the system. When a vehicle  600  is parked nearby the system and a driver is detected  640  by the face detection of the computer vision technology, the Interaction Initiation State  611  is started. At the Interaction Initiation State  611 , the VTOS can display welcome message or brief introduction about how to use the system. When the driver actually engages to the Driver Interaction State  612 , the VTOS provides the digital content for ordering or transaction through the display system  111 . When the user finishes the interaction, the VTOS goes into the Interaction Termination State  613 . In this state, the VTOS can display a brief parting comment like “Thank you. Come again!” message or any relevant content, which signals the user to the end of the interaction and lets the driver know what to do next as the result of the final interaction, such as displaying “Proceed to the next window!” message. When the interaction is terminated, the VTOS goes back to the initial Wait State  610  and prepares for the next driver. 
     FIG. 5  shows the exemplary maximum interaction range volume  431  and the exemplary optimal interaction volume  432  of the VTOS. The maximum interaction range volume  431  and the optimal interaction volume  432  of the VTOS are virtual space, which change according to the physical dimension of the driver and the vehicle  600 . The position and size of the virtual spaces can be approximated by the relevant position of the user and the size of the vehicle  600  window. 
   Since the volumes change according to the position of the driver and vehicle  600 , some degree of freedom for the motion is possible. This is helpful and necessary for the contact-free interaction  304  and the overall interaction process by the VTOS, because the vehicles  600  can be parked in random position within the vicinity of the VTOS units. If the image-capturing system  110  is static, the maximum interaction range volume  431  can reside within the field of view  320  of the image-capturing system  110 . If the image-capturing system  110  is dynamic, which can dynamically adjust the pan and tilt of the image-capturing device, the maximum interaction range volume  431  can extend further. 
   The maximum interaction range volume  431  shows the maximum range, in which the driver can interact with the VTOS. The maximum interaction range volume  431  is used to define the total area that can be used to track the face and hand. It is approximately located within the intersection of the image-capturing system  110  field of views  320 , which in turn is defined by the orientation and field of view  320  of the image-capturing system  110  for the hand detection and tracking. The VTOS is able to detect and enable the driver&#39;s hand gesture based contact-free interaction  304  within this region. However, in most cases, the driver will feel comfortable in interacting with the VTOS within the optimal interaction volume  432  because of the physical constraints. There is a limitation in the range of movement a driver can reach with his or her hand, so the optimal interaction volume  432  are decided by the position of the driver&#39;s face, where the person could interact with the VTOS comfortably. 
   The optimal interaction volume  432  is mainly used to detect the hand position, and the contact-free interaction  304  is accomplished within this volume. It is a sub volume that is located according to the position of the window of the vehicle  600  in the maximum interaction range volume  431 . If no window is present, the volume will be located according to the head position of the customer. To detect the position of the window, the vehicle  600  is analyzed by a computer vision technology as shown in  FIG. 6 . The silhouette  352  of the vehicle image  650  is determined using background subtraction. In the C. Stauffer and W. E. L Grimson, Adaptive Background Mixture Models for Real-Time Tracking, In Computer Vision and Pattern Recognition, volume 2, pages 246–253, June 1999, the authors describe a method for modeling background in more detail. Using the silhouette  352  and knowledge about typical vehicle geometries, the main color of the vehicle  651  is determined from the front section of the vehicle  600 . With the knowledge about the vehicle&#39;s color  651 , those regions of the vehicle silhouette  352  that do not have the same color as the vehicle  600  can be determined  652 . What remain are different parts of the vehicle  600  that do not share the same color as the body of the vehicle  600 , such as the wheels and the window region  653 . Finally, using edge detection and prior geometrical knowledge, the region that constitutes the driver window  653  is determined. 
   Then, the location and size of the optimal interaction volume  432  will be defined to optimize ergonomics (i.e., comfort and efficiency). This volume will preferably be located such that the user can use either the left or the right hand in a natural way. 
     FIG. 7  shows the VTOS dynamically changes the digital content display region within the vertically elongated display system  111  using the height detection capability. 
   The VTOS system can adjust the main content display region  532  in the display system  111  according to the user&#39;s height. Different type of vehicles  600  could have different heights. For example, the passenger cars usually have a lower height than SUVs (Sports Utility Vehicle). Different drivers in the same type of vehicle  600  can also have different heights. In order to make the virtual touch interaction more comfortable and reliable, the VTOS can adjust the height of the digital display region according to the level of eyesight of the driver in the field of view  320  using the computer vision technology, such as the face detection. For this functionality, the enclosure  100  of the VTOS can be equipped with vertically elongated display screens. For example, the display system  111  can position the display screen in a portrait style or use plurality of the normal display screens in a landscape style put together on top of another, in which the plurality of the display screens eventually make the entire screen a portrait style display screen. Using the eye level of the user, the main content display region  532  can be positioned in the corresponding level within the display screen. The other parts  550  of the display screen, where the main content is not shown, can be used for advertisement or promotional display for cross selling and up selling. 
   The design of the digital content widely depends on the owner or designer of the particular embodiment of the VTOS. The VTOS can be used for any drive-thru interaction, such as completing orders and transactions in a drive-thru bank, photo center, and quick service restaurant. Generally the overall content of the VTOS comprises welcome message, plurality of selection screens, and the exit screen.  FIG. 8  shows an exemplary screen shot of the digital content of the VTOS in the context of quick service restaurant.  FIG. 9  shows another exemplary screen shot of the digital content of the VTOS in the context of quick service restaurant. 
   In order to make the selection process more customizable, the maneuver button such as the back button  247  can be added. The title  554  could show the current position within the selection process. It could contain the conventional fast-food ordering items, such as food menu buttons  620  and soft drink menu buttons  621 . Quantity of the items  624 , size of the items  622 , and total  623  of the ordered food can be shown to the user also. The user is able to change the quantity of the items using the quantity change buttons  625 . The digital display contents clearly help the customers what they ordered. They can cancel and go back to the previous menu and make changes in their order. The selection process is done by the contact-free interaction  304 . Through the contact-free interaction  304 , the user is able to experience a new and exciting way of interacting with the ordering and transaction system. The buttons have to be easily noticeable as selectable items on the screen, to the customers. 
   After the customer completes the interaction, ordering or transactions, the VTOS can provide an exit screen. The content of the exit screen can be in any form, which informs the customer the end of the interaction, such as “Thank you. Come again!” message or “Proceed to the Payment and Pick up Window!” message. 
   The VTOS is able to collect the data using the computer vision algorithms, such as demographic classification, and analyzing the results of the ordered items and customer behaviors in selection processes, which can be saved after customers finish the interaction of making orders and transactions. This is the implicit way of collecting the data about the user, without requiring any user involvement in the data collection. 
   The data gathering services utilize computer vision technologies to provide visibility to customer traffic, composition, and behavior. This is explained in detail by R. Sharma and A. Castellano, “Method for augmenting transaction data with visually extracted demographics of people using computer vision”, U.S. Provisional Patent, 60/402,817, Aug. 12, 2002, and by R. Sharma and T. Castellano, “Automatic detection and aggregation of demographics and behavior of people using computer vision”, U.S. Provisional Patent, 60/399,246, Jul. 29, 2002. These services include detection of customers, their classification into segments based on demographics, and the capture of information about their interaction with the VTOS. The exemplary statistics gathered by the VTOS can include;
         the amount of time that is spent to finish the interaction;   the division of people in demographic groups, including gender, race, broad age group;   the traffic measurement, such as traffic composition by time of day, day of week, and demographic shifts; and   the customer behavior, such as the time spent at a particular item selection screen or whether the purchases are made or not.       

   This data collection in the VTOS enables immediate feedback of marketing initiatives, better understanding of customer behavior, and automated means of measurement. Retailers are constantly seeking to unlock the secrets to customer behavior, captivating them with meaningful communications in order to convert them into buyers of products and services. The data collection based on the computer vision technologies in the VTOS can provide the solutions for this business needs to make informed business decisions. The VTOS goes back to the initial Welcome Screen and starts look for next customer after the final interaction is made. 
   While the invention has been illustrated and described in detail, in the drawings and foregoing description, such an illustration and description is to be considered as exemplary and not restrictive in character, it being understood that only the preferred embodiment has been shown and described and that all changes and modifications that come within the spirit of the invention are desired to be protected.