Fabrication
The Fabric-Reinforced Controlled Motion Robot (FRCMR) is built in three sections and then assembled. A 3D printer is required. Most items are household items or can be purchased at a local hardware store. The Sleeve, Feet, and Bladders are fabricated separately before robot assembly takes place. A Degassing Chamber and Air Tanks are used in fabricating FRCMR.
 | frcmrcode.txt | 5 KB |
 | cadfiles.zip | 101 KB |
 | frcmr_bom.xlsx | 12 KB |
Sleeve
Materials:
| Time to Complete: 45-90 minutes |
 | Cut a strip of fabric 36” long and 6.5” wide mark lines 0.25”, 2.75”, 3.75”, and 6.25” inches from one long end. Cut an additional piece of fabric measuring 36” x 7.25” and one piece measuring 40” x 6”.
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 | Stack the 36’’ x 7.25’’ piece of material beneath the marked piece of fabric. There should be roughly half an inch of extra fabric on the top and bottom. Secure using staples or pins. Sew on the lines. |
 | Mark the center line of the 40” piece of fabric and mark lines 2.5’’ above and below the center line. |
 | Place the piece marked side down on the sleeve in progress. |
 | Sew two lines approximately two inches from each end of the sleeve (one side is pictured). The first line should be about an inch long, the second should be about 6 inches long. Leave about half an inch in between the two lines. |
 | Fold the top layer of fabric over and sew it on the marked line. |
 | Cut about an inch and a half down the center of the bottom layer. |
 | Trim the rough edges, remove the staples and secure the ends of the stitches with a drop of superglue. |
Feet
Materials:
| Time to complete: 60-120 minutes. (Not including 4 hour cure time) |
 | Cut a long strip of fabric (at least 26 inches long) that is at least 4 inches wide. |
 | Run two layers of Heat-n-Bond Hem along the length of the fabric at least 2 inches away from the edge.
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 | Fold fabric from the end and hem according to the instructions of the tape manufacturer. |
 | Trim the bottom of the hem line. |
 | Cut the strip into four pieces 5.75 inches long. |
 | Mark a line 0.375 inches from cut end of the strip. |
 | Mix about 50 grams of Ecoflex 00-10 according to package directions. |
 | Spread the Ecoflex on the side without the line. Wait 4 hours for the rubber to cure.
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Place the first strip of fabric, rubber side down onto new fabric. Sew two lines, one on the marked line and one 0.25 inch away from the marked line away from the rubber. Then sew the second strip of fabric so that the cut end sits on the drawn line of the fabric strip in front of it. Trim the excess base fabric. |
 | Repeat for second foot. |
 | Apply three layers of Heat-n-Bond Ultra to the underside of the base fabric. |
 | After the sleeve is completed, iron the base fabric patches to the completed sleeve roughly four inches from each end. Make sure the feet on both patches are facing the same direction. Apply heat to the opposite side of the sleeve. |
 | Heat one of the feet under an iron, Using a bamboo skewer, bend back the foot so that it is perpendicular to the sleeve. Hold the foot in place until it cools. When released, the foot should stay bent. Repeat for all the feet on the sleeve. |
 | Cut the feet so that each bristle is about 0.125” thick. |
Bladders
Materials:
| Time To Complete: 45-60 minutes. (not including 8 hours of curing) |
 | Mix 75 grams of Ecoflex 00-30 according to package instructions and degas the rubber. |
 | Carefully pour the rubber into the mold. Wait 4 hours for the rubber to cure. |
 | Remove the rubber from the mold. |
 | Puncture each end of the bladder and insert a short hose, at least 2 inches long. This allows the pressures to equalize when the mold is placed in the rubber. |
 | Make the second mold by tracing the plastic mold with hot glue, leaving about 0.25” on each side. Once cool, retrace over your existing glue to make the walls slightly taller. |
 | After the glue cools, pour a small batch of rubber into the mold. A good depth indicator is the metal nib on a Bic Pen.
Place the molds cavity side down in the rubber. Wait 4 hours for the rubber to cure.
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Remove the rubber, separate the bladders, trim the edges, and inflate. (Optional) If one side of a bladder inflates before the rest, paint it with more rubber. Allow the rubber to cure and re-inflate. Repeat until the bladder inflates evenly. |
Assembly
Materials:
| Time To Complete: 45-60 minutes. |
 | Insert one bladder into each of the three sections of the sleeve. Insert 4 pens into each sleeve (one for each long face of the bladder). These allow the fabric to easily slide down the bladder. |
Slide the sleeve down the pens. Once the pens go all the way through the sleeve, remove the pens and secure the bladders with zip ties on both ends. Trim the zip ties.
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 | Glue the top sleeve to the rest of the robot where the divider between the bladders sits. The center of the robot is determined by the bladders not the sleeve. Wrap each half of the robot with a zip tie. Make sure the robot can crawl and bend upward. Glue the top sleeve to the rest of the robot where the zip ties are and remove the zip ties. |
Accessories
Degassing Chamber
Materials:
| Time To Complete: 20 minutes. |
 | Step 1: Drill a hole in the cap of the jar. Step 2: Screw the fitting in the lid. Screw the lid on the jar. Step 3: Connect jar to the vacuum pump, then trace the fitting with hot glue. The vacuum will pull the melted glue though the any gaps, sealing it. |
Air Tank
Materials:
| Time To Complete: 20 minutes. |
 | Step 1: Puncture the lid of the bottle with a nail. Step 2: Thread about 0.75" of tubing through the hole in the cap. Step 3: Surround the tubing inside the cap with hot glue. Step 4: Before the glue cools, screw the cap onto the bottle, block the free end of the tube with your thumb, and squeeze the bottle. The pressure inside the bottle will push the hot glue though the any gaps and seal the bottle. |