This instructable is to make a aid that automatically removes a bedspread and closing it. We are students that had this assignment for the course Design for (every)one. In this course we need to work with a client that has a special need, for our case it is a person who has SMA type 2(Spinal muscular atrophy is a serious disease that causes nerves and muscles to stop working). This means the client can not lift any thing heavier then a small water bottle. Our client had a struggle in her bed, when she is too warm she could not remove the sheet from her to cool down. And when she was to cold, she could not place the sheets on top of her.

Our solution is a kind of caterpillar that is controlled with 2 strings. One string for removing the sheet and the other string that is located in the caterpillar to place the sheet back. The strings will be powered by a motor, the motor is not discussed in this instructable. A holder for the caterpillar is also mentioned.

Demonstration film

Step 1: The Materials

M5 countersunk bolts of 25mm long
M5 nuts
Some screw of 25mm long
1m of non stretch fabric (jeans is a good)
1 square meter of wood approx. 20mm thick (multiplex, natural, ...)
1m long wood plank of minimum 40mm wide and 15mm thick
2 wooden planks of 1m long, 25mm wide and around 8mm thick
5m of smooth ribbon
6 buttons

Step 2: The Tools

cordless drill (column drill is also advised)
wood milling machine
screwdriver
allen keys
sowingmachine
fretsaw

Step 3: The Milling

Before cutting the wood planks we first mill.

For the wide plank, cut a groove in the middle of approx 10mm wide and 1,5mm deep in his length. This groove is for the ribbon.

For 1 of the thin planks, cut a groove in the middle of 8mm (the wideness of the nuts) and 2mm deep in the length. Now the chamfer milling on each side of the plank, we used an angle of 60°.

Step 4: Cutting and Drilling

The cutting

The wide plank you cut in pieces of the same wideness as the thinner plank, the 2 thinner planks you cut as the same wideness as the wide plank.

The drilling

Drill holes of 8mm through the pieces, this step you can do before all the cutting when you measure everything up, or afterwards the cutting. Then you can hold the 3 pieces together and drill through all 3 in one drill movement.

The pieces where there isn't milled need a countersink in them.

Step 5: The Fabric

Cut the approximate length of the fabric with a wideness of 40mm extra as the wideness as your widest plank. now lay your thickest pieces on the length of the fabric, leaving 10mm of spacing on each side of the fabric. Mark the spots where the holes are for cutting them out. The cutting will work with a perforator. Another technique is stabbing the holes through with a thin pointy object.

Step 6: Sewing

After every segment is made, you can check the function of the construction (see next step). If everything checks out you can sew the edges and place some buttons on the side, and the counter buttons on the sheet.

Step 7: Assembly

First of you assemble the bottom part; this consists of the small piece with the countersink and the large piece with the ribbon in place. For the first piece you tie the ribbon around or tie a knot.

Then you place the fabric over and on that the piece with the chamfers. The last thing is to use the allen key to keep it all together. Do this for all the pieces.

Step 8: The Holder

This piece is to hold the previous assembly secure to the bed. These dimensions were all very situational. It can vary to your needs.

There need to be a flat surface on the frame of the bed where you can drill 1 hole in for this to work.

Step 9: The Cutting and Drilling

The general idea is 3 main parts and 2 other smaller parts.

Use the fretsaw to saw out these parts. First start with the middel part the long neck is for bridging the thick mattress. The segment where the rod is already in is where it contacts the bed frame. There need to be a hole there.

Secondly you saw the 2 other main parts that need to be symmetrical. The left segments of the part hook on the bottom side of the bed frame. You can shape them that way so there is a snugg fit.

The last parts are the smaller ones. These need to have a good length to be over the mattress. Another important thing here is the the incision for the fabric to slide into.

Step 10: Assembling the Holder

Assemble the parts using the screws with the wright spacings, you can pre drill holes and countersinks for a smoother part. When the holder is made you can sand the last piece of the other assembly down so it is a goot fit in the holder (see picture).