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P 15005 - Motorized Standing Platform Team Members Project Manager: Mike Fleszar (Industrial and Systems) George Bishop (Mechanical) Lawrence Fredsell (Electrical) Gabriel Luce (Mechanical) Olivia Robertson (Electrical) Alexandra Silberblied (Mechanical) Project Overview: The “Motorized Standing Platform” (MSP) is a device that assists and stabilizes an individual with Cerebral Palsy(CP) who is unable to stand balance on their own while participating in everyday activities. By taking an old Invacare wheelchair, the MSP has been transformed into a fully functional standing electric chair. The old drive system of the wheelchair has remained intact. However, in order for the chair to transform into a standing chair, an additional circuit was added. This circuit consists of two linear actuators that lift and control the positon of the chair. Since the user is unable to support themselves, various supports have also been designed to aid in standing as well as relieve pressure from their lower body. Customer Requirements Requirement Impor tance Requirement Achieved? Sit and stand capability 9 Yes Adjustable Controller placement 9 Yes Provides User Manuals 9 Yes Engineering Requirements Category General Yes Requirement Value Units Requirement Achieved? Speed 0 -5 Miles per hour Yes Total Weight chair can handle <200 Pounds Yes Size 52 x 29 Inches Yes Weather proofed Y/N Battery Life >24 Hours Yes Controller distance from body <30 Inches Yes Neutral Mode Y/N Adjustable arm rest 20 -30 Inches Yes Supports user’s weight by trunk >200 pounds Yes Θ 1 (while Standing) 120 -130 degrees Yes Θ 2 (while Standing) 90 -95 Degrees Yes Must fit in van and attach with 4 “s” clips 9 Balance chair to prevent tipping 9 Yes Keep user stable and comfortable in all directions while standing 9 Yes User able to reach multiple directions 9 Trunk Support 9 Yes Θ 1 (while Sitting) 0 -5 Degrees Yes Adjustable with growth 9 Yes Θ 2 (while Sitting) <30 Degrees Yes Long Battery Life 9 Yes <30 Degrees Yes Indoor/ Outdoor use 9 Yes Balance on incline while standing Operates Safely 9 Yes Made from commercially available wheelchair part 3 No Neutral Mode 3 Yes Longer Arm rest 3 Yes Adjustable armrest 3 Yes Easy to assist 3 Yes Able to reach workstation 3 Yes Second controller 1 No Color: purple 1 Yes Faster than normal wheelchair 1 No Additional accessories. 1 No Electrical Yes Mechanical Electrical System The complete electrical system is made up of two sub systems: the drive sub-system and the lift sub-system. The user is able to select which system can be operated at a time using a simple switch. The drive system consists of the original Invacare electrical controls and drive system and has not been altered. However if the lift system is selected, a separate circuit is powered and the position of the linear actuators can be adjusted to determine the height of the chair. There also three limit switches within the lifting sub-system that will shut off all power to the actuators once the chair has reached the desired positon. These limits insure the correct position of the chair is achieved as well as protects the linear actuators fro over extending and causing damage. Drive System Lift System Up Lift System Lifting System Testing A variety of testing was performed to insure that all systems functioned properly and safely. Some Tests performed • Actuator Load • Tip/balance • Electrical Function • Positioning • Fitting and Sizing Lift System Down In order to make the chair transform from a sitting to standing positon, a system of two linear actuators are used. Through the use of lever arms, the linear motion changes the angles of the back and seat. The angles and lifting speed were determined after hearing from medical supply expert and physical therapist. For comfort and safety, the chair doesn’t go to a fully vertical position. This allows the seat portion of the chair to support a portion of her weight and keeps the chair from tipping. An additional framing system was added on to support the larger back actuator. Comsol Strength Testing of actuator connectors Customer Megan during her first fitting Tip Testing on 13 Degree Incline Conclusion After making many modifications to the original base and electrical system. The MSP was successfully made and performs all functions as desired while completely supporting and stabilizing the user. In the future, the chair can be adjusted to stand taller once the user becomes comfortable and builds lower body strength. Acknowledgements The team would also like to thank Debbie Downey, Charlie Tabb, Beth De. Bartolo, Rob Kraynik, Matt Mc. Garvey and Mary D’Amico for their help and guidance throughout this design and build For additional information please visit: http: //edge. rit. edu/edge/P 15005/public/Home Support and Safety Systems Relieving pressure from the hips and lower extremities is the main objective of the supports added to this chair. A chest bar, shin pad, seat belt and footplate has been added to support the user. The seat’s angling also plays a large part in relieving pressure from the users legs.