P14253: Underwater McKibben Muscle
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Build, Test, Document

Table of Contents

Build, Test, and Integrate

Water-Jet

Water-Jetting of Finger and Hand Components

Finger profiles, finger plates, hand plates, and forearm plate were manufactured using a water-jet. This allowed for an accurate and high speed manufacture of the profiles of these components. This was an important process for this project since the finger shapes are complex and would require time consuming set-up on a CNC mill.

Water-Jet Profiles

Water-Jet Profiles

Machining

Bridgeport Mill

Bridgeport Mills were used to mill and drill all the hand components. The mills were also used in making the slots and holes in the cable tensioners.

Milled Finger Components
Lathes

Lathes were used to turn all cyclindrical components including the bushing, muscle fittings, and tensioners.

Lathes

Misc. Building and Assembly Pictures

For additional pictures please visit the photo section.

Misc. Testing Pictures

For additional pictures please visit the photo section.

Test Plans & Test Results

Arm Test Plans Documentation

Arm Test Plans Documentation

Arm Test Plans Documentation

Arm Test Plans Documentation

Assembly Instructions

Finger Assembly Instructions

1. Use the Tautline Hitch Knot to make four lines per finger. Make sure the knot is properly set before using in the finger.

Tautline Hitch

Tautline Hitch

80lb test Braided Fishing Line

80lb test Braided Fishing Line

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public/Photo%20Gallery/Photos/Fishing_knot_2.jpg

2. Disassemble current finger by removing the spring pins at the joint

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3. Line up the loop with the hole on end of the distal. Then Drive in spring pin. Finally tighten the knot down to be sung on the spring pin.

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4. Repeat step 3 for the other attachment point on the distal.

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public/Photo%20Gallery/Photos/Finger_Build_5.JPG

5. Slide in the bushing. Be sure to run the line from the far hole along the bottom (finger pad side) and the line from the attachment closest to the pivot point along the top (back of finger side).

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6. Slide the teflon tubes over the lines and then through the center hole in the middle section.

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7. Make sure the pivot point holes for the distal and middle are aligned with the bushing and then tap a spring pin in to complete the joint.

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9. Slide the longer teflon tubing over the lines and through the center hole for the proximal section.

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10. Slide in the bushing. Be sure to keep the lines running on the same side as before and pay special attention not to cross or twist the lines in the finger sections.

11. Make sure the pivot point holes for the middle and proximal are aligned with the bushing and then tap a spring pin in to complete the joint.

12. Do the same thing for the knuckle and you should have the following.

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public/Photo%20Gallery/Photos/Finger_Build_11.JPG

13. The two remaining lines can be lined up of the outside screws on the knuckle. Once they are tightened down on the screw, the screw can be tightened down into the knuckle.

Glove Schematic

Glove Schematic

Glove Schematic

Glove Specifications

Glove Specifications

User or Operator Instructions/Manual

Wiring Opposing Muscles for Arm Motions

When opposing muscles are connected and actuated slack develops due to the different rate at which the muscles contract and expand. To help eliminate slack and maximize rotational degrees at the joints:

1. Use a wire clamp to connect the wire to one muscle by threading it through the wire clamp, the eye hook on the muscle and then doubling back through the wire clamp

2. Tighten the wire clamp down by adjusting the nuts on the wire clamp

3. Fully contract the muscle the wire is connected to

4. Keeping the muscle contracted, move the joint (pulley) to the position you would like it to be during operation when this muscle is fully contracted

5. Hold the joint steady and tightly pull the wire over the pulley

6. Connect the wire to the pulley by tightening the bolt on the pulley

7. Connect the wire to the opposing muscle by repeating steps (1) and (2) with the opposite end of the wire

Service Instructions/Manual

Pump Troubleshooting

When operating the arm you may notice the pump will make a different noise and will not produce enough pressure to actuate the muscles. The likely cause of the problem an air bubble in the pump. This usually occurs at the beginning of operation or if the pump inlet tube becomes unsubmerged during operation. If this happens execute the following steps to correct the issue:

1. Shut the pump off

2. Make sure the pumps inlet tube is fully submerged in water source

3. Disconnect the valve inlet tube (the tube connecting the pump to the valves)

4. Run the pump till the tubing is purged of any air bubbles and the pump is running smoothly

5. Shut off the pump and reconnect all tubing


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