Abstract:
A powered mobility device for advancing cognitive, perceptual and motor abilities of a child lacking natural mobility is disclosed. The device includes a seat sized for the child to be secured therein and a motorized drive assembly coupled to the seat. A local operating instrument is operably coupled to the drive assembly for operating and steering the drive assembly. The local operating instrument is positioned to allow manipulation by the child seated in the seat. A processor is operatively coupled to the motorized drive assembly and to a local steering instrument. The processor is adapted to transmit a signal to the motorized drive assembly and the local steering instrument to control the mobility device. A method for advancing cognitive, perceptual and motor abilities of a child by using the device is also disclosed.

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
       [0001]    This application claims priority from U.S. Provisional Patent Application Ser. No. 60/977,297, filed on Oct. 3, 2007, which is incorporated herein by reference in its entirety. 
     
    
     STATEMENT REGARDING FEDERALLY SPONSORED RESEARCH 
       [0002]    The U.S. Government has a paid-up license in this invention and the right in limited circumstances to require the patent owner to license others on reasonable terms as provided for by the terms of NSF Grant # BCS-0745833, awarded by the National Science Foundation. 
     
    
     BACKGROUND OF THE INVENTION 
       [0003]    Self-generated mobility via locomotion is a key for the cognitive, social and motor development of young infants and certain children with special needs. Exploration of the world is one key to the rapid, significant advancement in cognitive, perceptual and motor abilities characteristic of early infancy. Two categories of skills provide the vehicle for physical exploration. The first to emerge is the ability to independently explore the local environment through reaching and grasping. The second is the ability to independently explore distant environments through locomotion. 
         [0004]    Over the first 8 months of postnatal life, typically developing infants gain the ability to reach for and grasp objects within their local environment. Such local exploration has been associated with rapid advances in social, cognitive, perceptual, and motor development. Exploration of the world by infants this age ultimately becomes limited by their inability to independently travel over distances. Consequently, these infants spend most of their time sitting and exploring the local environment that is within reach. For further exploration, caregivers must bring objects or playmates to them, or vice versa. 
         [0005]    Consequently, there exists a need for a device that provides the ability for such children to independently explore their world. 
       SUMMARY OF THE INVENTION 
       [0006]    Briefly, the present invention provides a powered mobility device for children. The device includes a seat sized for the child to be secured therein and a motorized drive assembly coupled to the seat. A local operating instrument is operably coupled to the drive assembly for operating and steering the drive assembly. The local operating instrument is positioned to allow manipulation by the child seated in the seat. A processor is operatively coupled to the motorized drive assembly and to a local steering instrument. The processor is adapted to transmit a signal to the motorized drive assembly and the local steering instrument to control the mobility device. 
         [0007]    The present invention further provides a method for advancing cognitive, perceptual and motor abilities of a child. The method comprises the steps of placing the child in the seat of the device described above; encouraging the child to touch the local operating instrument; and allowing the child to drive the device through operation of the local operating instrument. 
         [0008]    Further, the present invention provides a powered mobility device for children with limited personal mobility. The device comprises robotic drive assembly having a seat and a local operating instrument coupled to the robotic drive assembly to operate and steer the drive assembly. The local operating instrument is operable by a child seated in the seat. A plurality of sensors coupled to the robotic drive assembly and to the seat. The robotic drive assembly is programmable to respond to input from the plurality of sensors to change direction of the mobility device. The local operating instrument is programmable to move in response to the input. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0009]    The foregoing summary, as well as the following detailed description of exemplary embodiments of the invention, will be better understood when read in conjunction with the appended drawings, which are incorporated herein and constitute part of this specification. For the purposes of illustrating the invention, there are shown in the drawings exemplary embodiments of the present invention. It should be understood, however, that the invention is not limited to the precise arrangements and instrumentalities shown. In the drawings, the same reference numerals are employed for designating the same elements throughout the several figures. In the drawings: 
           [0010]      FIG. 1  is a side perspective view of a powered mobility device according to a first exemplary embodiment of the present invention; and 
           [0011]      FIG. 2  is a schematic view of an embodiment of an operational protocol for the powered mobility device illustrated in  FIG. 1   
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0012]    Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the disclosure without departing from the invention. 
         [0013]    Referring to the figures in general, a powered mobility device  100  according to an exemplary embodiment of the present invention is shown. Device  100  is a vehicle that allows infants and children with developmental disabilities to operate on their own in order to maneuver from one location to another. The child is seated in a seat and allowed to maneuver device  100  through a single action. 
         [0014]    Referring specifically to  FIG. 1 , device  100  includes a drive assembly  110 , such as, for example, the Magellan Pro robot, manufactured by iRobot of Bedford, Mass. Drive assembly  110  is maneuverable about 360 degrees, with a zero turning radius. Drive assembly  110  may be operated by a battery (not shown) that allows device  100  to operate without the encumbrance of a power cord. 
         [0015]    A seat  120  may be coupled to drive assembly  110 . Seat  120  may be sized to allow a user, such as an infant or small child, to be seated thereon. While drive assembly  110  and seat  120  are illustrated as discrete units that are coupled to each other, those skilled in the art will recognize that drive assembly  110  and seat  120  may be an integrated unit. 
         [0016]    One or more straps  122  (only one strap  122  shown in  FIG. 1 ) are fixed to seat  120  and may be used to secure the user in seat  120 . In an exemplary embodiment, seat  120 , along with drive assembly  110 , is sized for use with an infant or small child. Further, seat  120  may be coupled to drive assembly  110  such that drive assembly  110  is located in front of seat  120 . This arrangement places drive assembly  110  in front of the user when the user is traveling in a forward direction. 
         [0017]    A local operating instrument, such as, for example, a joystick  130 , is operably coupled to drive assembly  110  to operate and steer drive assembly  110 . Joystick  130  is located on device  100  such that joystick  130  is operable by a user  50  (shown in  FIG. 2 ) seated in seat  120 . In the exemplary embodiment shown in  FIG. 1 , joystick  130  is mounted to the top of drive assembly  110 . A diversionary device, such as a toy  132 , may be coupled to joystick  130  to attract the attention of the user and to encourage the user to operate joystick  130 . 
         [0018]    Joystick  130  is operable to maneuver device  100  forward and backward by pushing joystick  130  forward and pulling joystick  130  backward, respectively. In an exemplary embodiment, maximum speed in either forward or reverse direction is 0.2 meters per second. Operation of joystick  130  in either the right or left direction rotates device  100  to either the right or the left, respectively. In an exemplary embodiment, maximum rotation to either the right or the left is 14.3 degrees per second. With joystick  130  in a neutral position, device  100  does not move. Joystick  130  may be hard wired to drive assembly  110  or alternatively, drive assembly  110  may be controlled by joystick  130  through radio frequency. 
         [0019]    Drive assembly  110  and/or seat  120  may optionally include a plurality of sensors  112  disposed therearound. In an exemplary embodiment, sixteen sensors  112  may be spaced around drive assembly  110  and/or seat  120 . Sensors  112  may be infrared and/or sonar sensors that are able to sense an obstacle (not shown) in the path of device  100 . Device  100  may be programmable to respond to input from at least one of sensors  112  to steer away from the obstacle or to stop. 
         [0020]    Device  100  may also be programmable to transmit a signal to joystick  130  to manipulate joystick  130  toward a direction commensurate with the direction in which device  100  moves to steer away from the obstacle. Such manipulation of joystick  130  may provide a suggestion to the user that the user should manipulate joystick  130  in that direction in order to steer away from the obstacle. This manipulation is intended to correlate movement of joystick  130  with the directional change of device  100  to teach the user that the operation of joystick  130  influences the direction of motion of device  100 . The user, however, may urge joystick  130  in a different direction and override the suggestion provided by joystick  130 . 
         [0021]    A visual recording instrument  140 , such as a video or still camera, may be coupled to device  100  and positioned to record facial expressions of the user in seat  120  as the user operates device  100 . Viewing the facial expressions of the user may provide insight into cognitive awareness and perceptions of the user as the user operates device  100  and views his/her changing environment as device  100  moves. In an exemplary embodiment, recording instrument  140  may be mounted forward of joystick  130  so that the user cannot reach recording instrument  130 . 
         [0022]    Referring now to  FIG. 2 , in an exemplary embodiment, a remotely operated steering instrument  150  is in operative communication with drive assembly  110 . Remotely operated steering instrument  150  is programmed to override signals transmitted to drive assembly  110  by joystick  130 . An additional party, such as, for example, a caregiver (not shown), may use remotely operated steering instrument  150  to steer device  100  in a direction and/or to a location where the caregiver desires the user to travel. 
         [0023]    While device  100  may be used to allow a user to autonomously maneuver around, device  100  may also be used to obtain learning data from the user as the user operates device  100 . In this regard, a recording device  180 , such as, for is example, a notebook computer, may optionally be used in conjunction with device  100  to record the user&#39;s operation of device  100 . Displacement of joystick  130  may transmit radio frequency signals to recording device  180 , which both records the joystick transmitted signals and transmits an operating signal to device  100 . Additionally, recording device  180  may record the movement of device  100  relative to a starting point, as well as record signals transmitted by at least one of sensors  112  and the movement of device  100  in response to the input of sensors  112 . 
         [0024]    While recording device  180  is illustrated in  FIG. 2  as being separate from device  100 , those skilled in the art will recognize that recording device  180  may be integrated with device  100 , such as, for example, inside drive assembly  110 . 
       EXAMPLES 
       [0025]    Device  100  was operated by two different users to confirm their ability to operate device  100  as well as to obtain data to determine their learning curves. The results of these operations are discussed in Galloway et al., “Babies driving robots: Self-generated mobility in very young infants,” Journal of Intelligent Service Robotics, Special Issue of “Multidisciplinary Collaboration for Socially Active Assistive Robotics” vol. 1, no. 2, pp. 123-134, April 2008, which is incorporated by reference herein in its entirety. 
       Example 1 
     Elijah (Typically Developing 7 Month Old) 
       [0026]    This infant typically engaged joystick  130  with both hands and often with his mouth as well. While driving during initial sessions, Elijah was typically flexed forward over joystick  130  and looked at the walls, floor, objects and people as he passed primarily by moving his eyes. A preliminary review of videotape of his sessions suggested that, qualitatively, he did not typically turn his head or trunk while driving, and maintained a neutral facial expression. By the last sessions, Elijah sat more upright, and contacted joystick  130  less with his mouth. He rarely altered his course throughout a session. That is, if he started driving in a circle or straight at the beginning of a session, he continued to drive that path until coming to a barrier or obstacle from which an experimenter would use remotely operated steering instrument  150  to turn device  100 . He would then resume a circle or straight path, and continue so until reaching another barrier or obstacle. 
         [0027]    Data and conclusions developed during the course of Elijah&#39;s use of device  100  are as follows:
       1. Total session time: 147-416 seconds in the first three sessions (average 294 seconds) to 715-948 seconds during the last four sessions (average 819 seconds). This was a 170% increase in total session time.   2. Percent of total session time spent driving: 17-30% in the first three sessions (average 25%) to 47-64% seconds during the last four sessions (average 55%). This was a 125% increase in the percent total session time spent driving. In absolute time spent driving, the increase was from an average of 74 seconds during the first three sessions to 451 seconds during the last four sessions.   3. Total path length: 1-15 meters in the first three sessions (average 9 meters) to 37-74 meters in the last four sessions (average 58 meters). This was a 547% increase in the total path length.   4. Number of joystick activations: 4-32 activations in the first three sessions (average 20) to 18-79 activations during the last four sessions (average 46). This was a 132% increase the number of joystick activations.   5. Average duration of joystick activations: 3-24 seconds in the first three sessions (average 11) to 5-25 seconds activations during the last four sessions (average 14). This was a 28% increase in the average duration of activations.   6. There was a linear relationship between the percent driving time and total session time (R 2 =0.8). That is, the longer the session time the greater the percent of that time that was spent driving.       
 
       Example 2 
     Jackson (14 Month Old Diagnosed with Downs Syndrome) 
       [0034]    In comparison to Elijah, this infant typically engaged the joystick with one hand and rarely with his mouth. A preliminary review of the videotape of his sessions suggested that, while driving, Jackson sat upright and activated the joystick while turning his head and trunk to look at passing walls, floor, objects and people. He also altered his path several times a session such that a session&#39;s path contained straight segments and circles. Jackson also smiled and laughed while driving. 
         [0035]    Data and conclusions developed during the course of Jackson&#39;s use of device  100  are as follows:
       1. Total session time: 322-560 seconds in the first three sessions (average 464 seconds) to 709-1033 seconds during the last three sessions (average 853 seconds). This was a 80% increase in total session time.   2. Percent of total session time spent driving: 23-45% in the first three sessions (average 36%) to 37-54% seconds during the last three sessions (average 47%). This was a 30% increase in the percent total session time spent driving. In absolute time spent driving, the increase was from an average of 167 seconds during the first three sessions to 401 seconds during the last three sessions.   3. Total path length: 10-35 meters in the first three sessions (average 25 meters) to 41-73 meters in the last three sessions (average 60 meters). This was a 141% increase in the total path length.   4. Number of joystick activations: 31-33 activations in the first three sessions (average 31) to 22-73 activations during the last three sessions (average 53). This was a 73% increase the number of joystick activations.   5. Average duration of joystick activations: 2-8 seconds in the first three sessions (average 6) to 7-12 seconds activations during the last three sessions (average 9). This was a 49% increase in the average duration of activations.   6. There was a linear relationship between the percent driving time and total session time (R 2 =0.70). That is, the longer the session time, the greater the percent of that time that was spent driving.   7. During operation of device  100  during one of the sessions, an instructor used remotely operated steering instrument  150  on two occasions to redirect movement of device  100 .       
 
         [0043]    The two infants that were seen for multiple sessions displayed the opportunistic exploration that characterizes young infants. During the first session, both infants independently grasped and moved joystick  130  within minutes of being placed into seat  120 , and continued to move device  100  for many minutes over many meters of motion. Over multiple sessions, both children increased their total session time, reflecting their ability to tolerate sitting in and moving device  100  at least once each 5 minutes up to a maximum of a 20 minute session. These infants increased their tolerance from 5 to 8 minutes on average over the first three sessions to 14 minutes on average over the last three sessions. Data recorded during their driving reveals they did not simply produce the minimum joystick activations, but rather produced a relatively high level of joystick activity. By the last session, both infants were driving more than 50% of the time they were in device  100 , which was double their starting percentage and resulted in approximately 8 minutes of active driving time. This level of activity is important to be able to train young infants to accomplish tasks by driving to specific locations or around obstacles, which will require sustained periods of active problem solving. Learning experiments in which infants are involved in problem solving suggest that actively moving device  100  for 10-15 minutes or more will provide a baseline of activity from which infants can learn to associate joystick motion with mobile robot motion. 
         [0044]    Both infants drove for longer path lengths over sessions; however each did so with a different pattern. Path length increased abruptly on session  4  for Elijah, whereas path length gradually increased over each session for Jackson. Each infant also displayed a different manner by which they increased the path length over the last three sessions. Elijah increased path length by increasing the duration joystick activations while decreasing the number of activations, whereas Jackson increased path length by increasing the number of joystick activations. Such individualized changes are also a common feature of learning and development in infancy. 
         [0045]    These results demonstrate that young infants will independently move themselves via a mobile device, such as device  100 . The data do provide indirect evidence that infants were not simply focused on moving joystick  130  but were associating joystick activation with their motion. First, infants did not habituate to joystick  130 . It is well known that infants will decrease their responsiveness with repeated presentations of the same situation or task. Joystick  130  used in the above study was not colorful or particularly interesting compared to the toys these infants spent their days with in their classrooms and at home. Thus, if the infants were focused solely on joystick  130 , it may be theorized that their responsiveness would have decreased over time within a session and between sessions. In contrast, their joystick activations increased in number and/or duration resulting in increased driving time and path length. 
         [0046]    For both of these infants, device  100  provided the first experiences of self generated mobility over long distances. Elijah, as a typically developing infant, is will likely begin to walk around 12 months of age. Jackson, however, has a diagnosis of Down Syndrome. Children with Down Syndrome often have delays in attaining the major developmental milestones such a walking and speaking. Many also have mild to moderate cognitive impairments. At 14 months, Jackson was not yet pulling to stand and thus was at risk for delays in walking. Interestingly, other infants Jackson&#39;s age explored the various components of device  100 , but did not drive. Thus, Jackson performed as a somewhat younger infant in device  100 , which probably was related to his somewhat lower cognitive and motor abilities at the time of testing. 
         [0047]    While the results described above do not provide direct evidence that these infants were purposefully driving to specific locations, the protocol for this study was designed to gather data for future studies involving training, and was not structured to formally quantify learning, memory or purposeful actions. It is theorized, however, that the motion of device  100  was reinforcing to joystick movement. That is, infants were rewarded for joystick motion with self motion. 
         [0048]    It is theorized that even very young infants are able to associate body movement with motion in the environment, and remember this association for many days. In an exemplary method of testing this theory, infants are allowed to interact with a non active joystick (baseline condition), then an active joystick resulting in self motion (acquisition condition), then a non active joystick (extinction condition). If infants associate joystick motion with self motion, joystick activations during extinction should be greater than those during baseline. Moreover, memory is shown by comparing baseline levels on Day 1 with baseline levels of subsequent days. Such associative learning is a critical step in the development of purposeful behaviors. The next step in the exemplary method may include showing that infants prefer to activate a joystick that results in self motion. This exemplary embodiment includes combining the training of young infants, both typically developing and those with mobility impairments, with mobile robotics technology to allow infants the ability to display increasingly complex self generated mobility. Thus, complex mobility is the primary outcome with the advancement of general development being an expected result of increased mobility. One area of application of mobile robot technology is in the area of power mobility for infants and children with special needs. 
         [0049]    Although the invention is illustrated and described herein with reference to specific embodiments, the invention is not intended to be limited to the details shown. Rather, various modifications may be made in the details within the scope and range of equivalents of the claims and without departing from the invention.