Concept Proposal for Variable Speed Hospital Bed Back Support

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Concept Proposal for Variable Speed Hospital Bed
Back Support

• As written for the 2006-2007 AMI National Student
  Design Competition

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Team Members

• Andrew Burian
• Andy Cash
• Yoshiko Ishibashi
• Jeff jones
• Kelly McGowen

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Problem Statement

• To design a reliable, ease-to-use, EPP-based
  power-assist Back angle controller for a
  prototype platform (or hospital bed or exam table)

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Competition Required Specifications

• Bed side mounted operating lever or handle that
  is easy for a caregiver to reach and grasp
• Patient input for to vary normally from 1-20 lbs
• More force more speed
• Caregiver input to be 1-5 lbs but to operate at
  lower speeds
• Must be stable during and after adjustment and if
  power is lost

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What is EPP?

• EPP (Extended Physiologic Proprioception)
  describes how a mechanical object or system
  feels to the user. With respect to this
  project, the harder a patient pushes on the
  control lever, the faster the angle adjustment
  mechanism will adjust. Or simply put, the bed
  will act as an extension of the patients arm.

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Customers

• Patients
• Caregivers
• Maintenance Personnel
• Manufactures
• Sales Associates
• Government (Regulations)

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Customer Requirements

• Smooth Motion
• Variable Speed
• Large Weight Capacity
• Low Accelerations
• Manually Operated
• Default Position
• Light Weight
• Recognizable Controller
• Made From Recyclable or Reusable Component or
  Materials
• Adjustability W/O Power
• Clean Operation

• Stain Resistant
• Corrosion Resistant
• Easy to Manufacture
• Made from Off the Shelf Parts
• Easy to Maintain
• Slip Resistant Controle Surface
• Entrapment Proof
• Extended Mean Time Between Failures
• Motion Lock-Out
• Stable W/O Power
• Easy to use

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Engineering Specifications

• Patient Weight
• Speed
• Life Cycle
• Maintenance Intervals

• Range Of Motion
• Force on Controller
• Sound Level
• Vibration
• Acceleration

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Bench Marks

• Current Bed
• Collects dust
• Jackscrew, with transmission
• Goes to 45
• Very slow
• Has lasted 30 years and still works

• Hill-Rom Bed
• Hard to clean
• Hydraulic power
• Rises to 74
• Slow ascent and descent
• State of the Art

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Functional Mapping
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Concept 1

• Hydraulically powered
• Variable Speed Going up
• 1-speed coming down
• Variable Speed Pump
• Failure possible due to leaks

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Concept 2

• Jackscrew
• Variable Speed Motor
• Variable speed coming up and going down
• Failure due to stripping of threads

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Concept Comparison
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Comparison Cont.
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Choice Jack Screw

• More Technologically Ready for Our Design
• Fits All Design Criteria