2002 Conference Proceedings

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Albert M. Cook1, Brenda Bentz2, Cheryl Card3 Hae-Young Kim1 and Max Meng3

1Faculty of Rehabilitation Medicine
University of Alberta
Edmonton, Alberta T6G 2G4

2Edmonton Public Schools
Edmonton, Alberta T5G 0B7

3Advanced Robotics and Teleoperation Laboratory
Faculty of Engineering
University of Alberta
Edmonton, Alberta T6G 2G4


Children who have severe physical disabilities are generally unable to grasp objects, control their upper limbs, walk independently or speak. The severity of their physical disabilities also limits the assessment of their cognitive and language skills. Research indicates that play promotes the development of environmental exploration. The purpose of this research is to determine how children can use a robotic arm for environmental exploration and to engage in social interaction via play.

Battery-powered toys and adapted computers as used to compensate for a child's limited manipulative abilities. This approach simulates a range of play experiences that allow discovery and exploration. Switches that are activated by gross body movements are used to control these toys and programs. Toys, however, are limited to a few functions and children often lose interest in them relatively quickly. Computer-mediated play ranges from simple cause and effect programs to more complex programs requiring children to make decisions and engage in more sophisticated control of the software. Although computers allow a mediated version of play for children with disabilities, it is not the same type of play as that which is done by a child with real objects. For these reasons we have explored the use of robot enhanced manipulation of real objects by children who have severe physical disabilities.


1. To evaluate how children with severe physical disabilities can physically control a robotic arm to engage in functional play tasks.

2. To determine the impact of the use of a robotic arm on children's behaviour, social and academic performance.


Ten children who had severe physical disabilities participated in this study. Their ages ranged from 5 to 12 years old. The functional anatomical sites used by the children for switch control included head, hand, elbow and foot movement. The children were unable to engage in play or educational activities independently or with other children or adults.


The Rhino XR-4 robot is a 5-degree of freedom robot arm that can move similarly to the way a human arm can move. The robot can rotate around its base, bend (flex/extend) at the shoulder, elbow and wrist, and rotate (supinate/pronate) its wrist. It can also open and close its two-fingered gripper. The robot is mounted on an aluminum base to ensure stability when the arm is fully extended. Each of the motors on the robot has an encoder, which provide feedback to the robot controller regarding the position of each motor.

The robot is controlled using the Rhino Mark IV controller. The Mark IV can be programmed to allow the robot to perform a wide variety of movements. It can also be used to interface control switches to the robot. These switches are the means by which the child controls the robot. The controller is also connected to a laptop computer. The computer allows the researcher to modify the parameters of the robot's behaviour to match the abilities of individual children.

Three play tasks were used:

Task 1: The arm dumped macaroni from a glass using one switch-hit. The adult's role was to fill up the cup with macaroni (by hand). The child's task was to hit a switch causing the robot arm to DUMP the macaroni that the adult would catch. The child then indicated that the cup should be filled again (typically by looking at the cup).

Task 2: The child used two switches: (1) dig an object (e.g., a plastic egg with some kind of small toy inside) out of the macaroni, and (2) to dump the macaroni and object. The adult's role was to bury the egg, catch the egg when the child dumped it out and open the egg for the child when the child requests it (e.g., by looking at the egg).

Task 3: The child used three switches (1) to position the robot arm for digging, (2) scoop or dig an object (e.g., a plastic egg with some kind of small toy inside) out of the macaroni, and (3) to dump the macaroni and object. The adult's involvement was the same as for Task 2. Once the child positioned the robotic arm, the task was identical to task 2. The scooping or digging movement required from one to 8 switch hits to complete.

Each child's session using the robotic arm was video taped for later analysis.


Goal Attainment Scaling (GAS) was used to evaluate objective #1 GAS is a criterion referenced, individualized measure of the impact of an intervention such as the use of the robot arm for play (Kiresuk, Smith and Cardillo, 1994).. The advantage of GAS is that it accommodates the multiple, individualized goals that were developed for each child. Examples of goals are:

Scale #1: Play Scale #2: Control of the robotic arm
-2 Un-responsive to play Completes only one task (dump)
-1 Engages in play only with prompting Complete two tasks (dig and dump)
0 Spontaneously engages in play Completes three pre-programmed tasks
+1 Initiates play activity with adult Three tasks with 2 step "move"
+2Maintains and directs play activity Three tasks with multiple step "move"

T values (Kiresuk, Smith and Cardillo, 1994) were calculated pre and post robotic use for each child. The majority of the children in the study had improved T scores (higher scores on goals) after using the robotic arm for a period of approximately four weeks.

In order to evaluate objective #2,(determination of the impact of the use of a robotic arm on children's behaviour, social and academic performance) we used two series of open-ended questions: one for the teacher and one for the parent. These open-ended questions were aimed at establishing the perceived difference in the child after interaction with the robotic system and to provide insight into the child's social and academic performance before and after using the robot. This type of 1 - 1 interview is flexible and ensured a high response rate. Qualitative analysis of the interview responses was conducted to determine themes in the overall responses. In general, teachers noticed differences in overall responsiveness, amount of vocalization and interest (i.e., greater attention to tasks, or longer attention periods) for children who used the robotic arm. All teachers reported that the students enjoyed using the arm and looked forward to the periods when they were able to use the robot.


The results reported here are an extension of an earlier study in which the children used the robot in a laboratory session over a limited number of sessions (Cook, Howery, Gu and Meng, 2000). The extended use of the robot in a school setting gave an opportunity to study learning by the children as well as to investigate secondary results that occurred in the classroom as a result of the use of the robotic arm. We found that significant learning by the children did occur and that there were noticeable effects in their overall behaviour and performance during and after their use of the robotic arm system.

AKNOWLEDGEMENT: This research was funded by the Children's Health Foundation, Edmonton, Alberta


Cook AM, Howery K, Gu J and Meng M, (2000), Robot Enhanced Interaction and Learning for Children with Profound Physical Disabilities, Technology and Disability, 13(1): 1-8.

Kiresuk TJ, Smith A, and Cardillo JE (eds) (1994), Goal attainment scaling: Applications, theory and measurement, Hillsdale, NJ: Erlbaum.

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