Introduction: Portable Stop-Motion Animation Station
I built this for a friend, who works with youth creating digital media. She'd seen a large 'animation station' exhibit at the San Francisco Exploratorium, and wanted a something similar that she could travel with. This was a fun weekend build, and doesn't require much in the way of specialized tooling or difficult techniques. It's entirely possible to make stop motion animations without a device like this, and using a tripod with a DSLR can give you much more flexibility - but having a purpose built device that enforces limits on how the video is shot is a great way to encourage creativity in the content produced.
The Animation Station is a rigid wooden panel, painted matte black. Two lamps are mounted to the panel on flexible goosenecks, which illuminate the surface of the panel. An HD video camera is mounted at the end of a rigid arm, which extends over the panel. The camera arm can be quickly detached, and the entire assembly can be stowed securely in a modified suitcase.
This instructable will cover the construction of the animation station, the suitcase modifications, as well as the open source software I used to create the short test video above.
Step 1: Base Panel
The base panel is built from pine 2x2's and 1/4" plywood. It has a 1.5" square cut out at one corner where the vertical camera arm will fit. The 2x2's help keep the panel rigid and provide an interior space to mount electronics later.
- To construct the panel, first cut the plywood into a rectangle of the appropriate size. I measured the inside of the suitcase, leaving a few inches of space around the edges to determine the size of my panel, but you should choose a size that works for your application.
- Cut the pine 2x2 sections, cutting one short by 1.5" (the true dimension of the 2x2) to leave one of the corners empty.
- Glue and screw the 2x2 section to the panel, countersinking the holes so that the screws lie slightly below the surface of the plywood.
- Cut the corner notch flush with the 2x2s. I did this with a 'clean cut' blade on my jig saw, but you'll notice there was still significant tear-out on the plywood surface. I recommend clamping a piece of scrap plywood to the surface of the panel before making this cut, to prevent this from happening. In my case, I repaired the damage with wood putty before painting the surface.
- Use wood putty to cover all the screws. I like to apply a thick coat of wood putty that's slightly raised above the surface, then sand it flat later. You can also fill any small imperfections and knots in the plywood surface at this point.
Step 2: Mounting the Lights
I used inexpensive LED lamps for the lighting. The specific ones I used were available for $10 each from my local IKEA. The lights are designed to screw into a weighted base, and I was able to re-use those screw mounts to attach the lamps to the base panel. If you're using similar lamps, follow the directions below to mount each lamp, otherwise, improvise a mount that works for you.
- Use a forstner or spade bit to drill a hole large enough for the lamp base through the side of the base panel.
- Measure the distance between the two nuts in the base of the lamp, and transfer this distance to a 1.5" x 3" piece of plywood.
- Drill holes for the lamp's mounting screws through this piece of plywood, and mount the lamp base to it. Before mounting it, I chiseled a small groove in the plywood to provide clearance for the lamp's power cord.
- Cut two blocks from 2x2 stock. Screw these to the large base panel on either side of the hole you drilled in step one, leaving room for the lamp base.
- Finally, screw the small piece of plywood attached to the lamp base to these two blocks. Now the lamp base is securely attached to the base plate.
Step 3: Wiring the Lamps
The lamps each come with a small switching DC power supply. Rather than try to find a single new power supply that could power both lamps, I decided to use the two supplies I already had. I used solder and heat-shrink to do the wiring, but this could also be done with wire nuts if you don't have a soldering iron.
- Cut the end off an ungrounded extension cord. A grounded cord will work too, but because the power supplies don't have a ground pin, there's no reason to buy the more expensive and heavier cord.
- Strip the insulation from the end of the cord, and attach each wire's end to one of the blades on the switching power supply. I like to make sure the wire coming from the large blade on the extension cord's plug attaches to the large blade on the power supply's plug, but this isn't really necessary in this application.
- Using additional wire cut from the discarded end of the extension cord, wire the first power supply's blades to the second.
- Use electrical tape and heat-shrink it insulate all connections.
If you're working with wire nuts instead of a soldering iron, you'll need two extension cords. Cut them in half and attach both ends onto one of the cords using the wire nuts. It's also possible to find extension cords that have multiple ends, but none of the ones I could find allowed the power supplies to mount within the bottom of the panel without poking out.
Once the electrical wiring is done, it's time to mount the switches and power supplies.
- Hot glue the switches to the outside edges of the panel.
- Using a chisel or dremel, cut grooves in the panel's base that the wires can run it. Hot glue the wires into these grooves.
- Hot glue the power supplies to the inside of the main panel.
- Use zip-ties and hot glue to secure all loose wires to the inside of the main panel.
Step 4: Camera Arm Quick Release Mount
The camera arm needs to easily detach from the base, but quickly and rigidly reattach. A pair of draw latches provide the clamping force needed to hold the arm in place, while a pair of positioning blocks help make the placement of the arm repeatable, precise, and stiff.
- I chose these particular draw latches because they fold flat , which made it easier to fit the panel into the case when completed.
- Mount the latches to the base panel so that they overhang the notched corner as shown in the photo. At this stage, precise placement is not important - I located the latches so that their far ends were near the middle of the notched corner.
- Next, I mounted the catches to a piece of 2x2 that became the vertical section of the camera arm. These were located precisely so that the draw latches developed a strong clamping force when fully retracted. I carefully marked the screw hole locations, then used a punch to indent the wood so that when I pre-drilled the screw holes, the hole placement would be precise.
- Finally, I cut small blocks of 2x2 and screwed them to the vertical arm so that they rested on the surface of the base panel. Note in the photo that the bottoms of these blocks are slightly undercut, so that they touch the base panel at their far edges. This helps to stiffen the vertical arm.
Step 5: Camera Arm - First Try
Initially I wanted the arm's vertical height to be adjustable, but later revised the design when it became clear that this added complexity and wasn't an important feature for the end-user. This step documents that first design, but can be skipped if you also aren't interested in an adjustable camera height.
The idea was to drill a series of 1/4" holes through opposite corners of the vertical section of the camera arm. A bolt would pass through these holes and screw into a threaded insert placed in the end of the horizontal section of the camera arm. This required both a compound blind miter cut into the end of the horizontal section (marked out in the photo above) and a series of precise holes drilled into the vertical arm.
I don't have a drill press in my home workshop, so the holes in the vertical arm presented a challenge. I built the jig shown above to repeatable locate the holes, and used the drill bushings in a doweling jig I had from a previous project to drill holes at right angles to the top plate of the jig with my hand drill.
The miter cuts on the horizontal arm were made with a hand saw, then cleaned up with a chisel to fit precisely. A long wing-head thumb screw allowed the arm to be moved without tools.
Step 6: Camera Arm - Final Version
The second, simpler design for the camera arm uses a fixed height mount. I chose a cylindrical camera (a Microsoft H5D-00013 LifeCam) since it was easy to build a mounting fixture for. If using a different camera, you may have to improvise a different style of mount. To build the mount shown above, I followed these steps.
- I made a 15 degree compound miter cut at the top of the vertical element so that the horizontal arm would rise slightly when mounted.
- I clamped the horizontal arm in place and drilled through it and into the vertical arm with a 5/8" bit. I inserted a 2" hardwood dowel into this hole, gluing it in place to hold the two arm sections together. The dowel provides a very strong joint at the elbow, which could experience a large load if the arm were dropped or bumped.
- I used a hand plane to smooth the transition from the horizontal arm to the vertical arm, so that there aren't any overhangs or gaps. This could be done with a hand saw or jig saw and sandpaper, if you don't have a hand plane.
That completed the main arms. Next I built the camera mount.
- First, drill a 1-1/8" hole in a piece of scrap pine.
- Cutting out the outline of the clamping jaws around this hole.
- Cut again to separate the two sides of the jaws.
- Use a dremel or chisel to adjust the jaw shape to fit the camera. In my case, I removed material to accommodate a bulge for the microphone.
- Glue a strip of leather or thick cloth to the inside of the jaws, so help provide more even clamping force.
- Drill two 1/4" holes through the jaws on either side of the camera hole. I used socket head cap screws inserted through these holes and secured with nylock nuts to provide the clamping force on the camera.
- I attached the vertical block that connects the jaws to the horizontal arm using 1/4" dowels at each end.
- The final positioning of the camera mount was done with the camera plugged in, so that I could verify that I had the desired region of the base plate in view.
- I secured the camera's cord to the camera arm with zip-ties.
Step 7: The Suitcase
I built a harness for the base panel and camera arm out of nylon webbing, and attached it to the shell of the suitcase. I also sewed a small drawstring pouch to protect the camera from dust and scrapes.
- I used scrap webbing and parts that I had on hand, but these materials are typically available at hardware stores, craft stores, and internet specialty retailers.
- I sewed the webbing using plain nylon thread on a home sewing machine. Don't forget to melt the cut ends of the nylon so it doesn't fray, and go back-and-forth over your stitches 2-3 times to make sure the connections are secure.
- To attach the webbing to the suitcase I used 1/8" pop rivets, because I wanted to keep a low profile on the outside of the case. If you don't have a pop-riveter, you could use pan-head screws with nylock nuts on the inside for a similar effect.
- When inserting the rivet through the nylon webbing use an awl or pointed tool to spread the nylon fibers without cutting them. This will help avoid fraying and failure of the strap in the future.
Step 8: Software for Making Videos
I used open source stop motion software called FrameByFrame to make the test video. While there are several free and low-cost stop motion software packages, one feature not provided by the one I used is the ability to put a USB camera into a fully manual mode.
When making a stop motion video it's important that the camera's internal settings, like exposure, gain, white balance, and focal distance, not change from frame to frame. This can create a number of undesired flickering effects. Linux has simple support for this type of manual control, and on other operating systems your camera's drivers may provide it already. Since the end-users of the Animation Station will be using OSX, I found a low-cost solution in the "Webcam Settings" app by Mactaris, which worked well with the particular camera I used.