The Driver’s Seat

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The Driver’s Seat

Students: Rob Hayes, Mantoua Green, Brad Baird
Client Coordinators: Gary Edwards, PhD, Marlese Delgado, PT, United Cerebral Palsy of Birmingham


The present project is a modified floor sitter, which allows children with cerebral palsy to sit in a position that allows them to play with other children at floor level.  It is based on the following dimensions of the user: 10”-15” arm length, 7”-10” shoulder width, 8”-12” seat to shoulder height, with a 50 lbs weight limit. The child is secured in the sitter by a restraining system (seat belts and straps), capable of being loosened and tightened to increase or decrease the pressure/force needed to keep the child’s back and neck in position parallel to the rigid structure.

Technical description


The final design is constructed out of ash (Figure 9), which is a fine grain wood ideal for construction of small, lightweight components requiring high strength.  The fine grains of the wood are also ideal for preventing splintering and fracture.  The sitter is sealed with a low gloss-polyurethane, non-toxic coating, which will further prevent warping and bowing associated with environmental conditions such as humidity and temperature. The coating conforms to Section 4 of ASTM standard F 963-92.  A hinge and lock design mechanism with positive locking pins maintains a backboard structure capable of positions ranging from 20 (folded forward) to 125 (completely extended). The back support is allowed to rotate by a set of wide-leaf utility hinges. Locking pins are used to secure the back supporting structure at the appropriate angle.  The ball, ring, spring, shank, receptacles and spindle are stainless steel.   The floor sitter is lined with a urethane padding upholstered in washable vinyl. A four-point chest support strap (Bodypoint harness Rubatex) along the back supporting structure is used to keep the spine and head erect and aligned. Velcro attaches the chest support to the back support and keeps the child’s pelvis correctly oriented in the chair, stabilizing the posture and controlling movement in a neutral motion. Metal end-fittings and slides are provided for a strong, adjustable means of attachment.  Medial placement of secondary straps secures the position of the pad and keeps the hip belt from riding up into the abdomen.  The seat belt is adjustable and locks in place.  An adjustable footrest, purchased form a supply company, is held in place with a set of plastic dowels.  Racecar stickers are added to the final product to enhance the racing theme of “The Driver’s Seat”.  The total cost is less than $500.

9 - drivers seat
Figure 9. The Driver’s Seat.