Introduction: Motion Machines
Motion Machines provide a playful introduction to motion, mechanism and robotics. The kits are made up of a lasercut plywood body and simple bulk parts like slow moving gear motors, plastic battery packs and slide switches. Learners can experiment with switching the size and shape of laser cut wheel attachments and changing the direction of the motors to make bots that spin, scoot and shimmy.
This guide is a rough draft! We are still working to develop this playful tool for exploration. Feel free to remix the designs and let us know what you come up with as you experiment in your museum, classroom, makerspace or kitchen table.
Step 1: Gather Materials and Tools
Buy or collect the Following materials:
2 three position DPDT slide switches
2 3D printed hubs
2ft x 4ft common underlayment 5mm Lauan sheet for laser cut bodies
4 #8-32 nuts
4 #8-32 x 1 1/2in machine screws
6 #2 x 3/8 screws for switches and hubs
2 #8 1/8 in wood screws for battery packs
black and red stranded wire #26 AWG
Collect the following tools:
Hot Glue Gun
Philips head screwdriver
Needle nose pliers
You'll also need access to a laser cutter and a 3D printer. We used a Prusa i3 MX2 for the 3D printer and a EXLAS laser from Jinan XYZ machinery (both at the Ace Monster Toys Makerspace in Oakland.
Step 2: Lasercut the Bodies
Use illustrator and laser cutter software to import the attached file motionmachinebodies.dxf and cut the bodies according to your laser cutter settings.
If you don't have access to a laser cutter you can cut out two 4in by 4in squares of the lauan sheet. Then drill 3/16in holes in the corners (lined up on the two sheets) and two .35 in x .60 in rectangles in the middle (for the switches).
Step 3: 3D Print the Connector Hubs
We designed a special part in Tinkercad to make it easier for learners to quickly test out different shaped wheel hubs and relieve some of the pressure on the little motor axle.
Download the motionmachinehub.stl file and open it on your 3D printer software. As you print out the two wheel hubs, make sure to test that the printed part first snugly on the motor axle. You may have to adjust the size of the part to make sure that it fits on the motor.
Step 4: Connect the Circuit
Get motors, swich, battery pack, red and black (or any two colors of wire). Set aside one motor, switch and battery pack.
Cut a piece of red wire and a piece of black wire approx 3in long. Connect the red wire to the bottom left lead and the black wire to the bottom right lead of the switch.
Take the other end of the black wire and twist together with the exposed end of the black wire from the battery pack. Solder the twisted together ends to the top left lead of the switch.
Take the other end of the red wire and twist together with the exposed end of the red wire from the battery pack. Solder the twisted together ends to the top left lead of the switch.
Attach one black and one red wire to the two leads on the back of the gearmotor.
Connect the black wire from the motor to the right middle lead and connect the red wire from the motor to the left middle lead.
Put a battery in the holder and test to make sure the motor goes forward, backwards and off when the switch is in the middle position. If it doesn't work check to make sure that none of the wires are touching in the middle of the switch. You might have to bend the leads outward.
Repeat these steps for the other side.
Step 5: Attach Elements to the Board
Turn the switch sideways and thread it through the board. Test that the motor runs the correct direction before screwing switches on the top board with the #2 x 3/8 screws.
Hot glue the motors to the board so that the axle is in the center of the body. Try to tuck the wires neatly or add a dab of hot glue so that they stay in place.
Use the 1/8 in woodscrews to attach the battery packs in the center of the body above and below the slide switches.
Attach the 3D printed hubs to the axles and use the #2 screws to secure the piece to the machine.
Step 6: Connect the Top and Bottom Layers
Use the #8-32 nuts and machine screws screws to connect the top and bottom boards together. The fit should be snug but not putting too much pressure on the machine.
Test everything to make sure that it's working.
Step 7: Cut Wheels
Use illustrator and laser cutter software to import the attached file motionmachinewheels.dxf and cut the bodies according to your laser cutter settings.
The shape can be a little tricky to get right depending on the settings of your lasercutter. Test the first wheel and then adjust the size to be a snug fit on the motor hub.
If you don't have access to a laser cutter, you can skip the 3D printed piece, buy prefab wheels on Sparkfun and glue different shapes or recycled materials to the base.
Step 8: Experiment With Different Movements
Connect the wheels to the machine and turn on the motors.
Can you make the board travel in a straight line?
Can you make small or large circles?
Can the machine look like it’s dancing?
Can you make a machine that can traverse different surfaces?
Think about the ways that the arrangements of wheels change the personality of the machines.
Step 9: Customize Your Machines
If you want to add a little more personality to your boards you can paint the bodies. We made custom stencil stickers using a Silhouette vinyl cutter and spray painted the bodies.
Feel free to also add extra elements like markers, bells, googley eyes or extender arms to your machines. These remixes and character designs can add to the storytelling elements of this activity.
Step 10: Tinkering With Motion Machines in the Classroom
We designed these elements to be a friendly workshop with students at a local school. We tested the boards with learners from kindergarten to fifth grade as well as at East Bay Maker Faire. We think that this activity can be used both as a open-ended activity during free time as well as be integrated into larger robotics, electronics or programming curriculum as a first step.
When working in the classroom environment, two students can share one board and collaborate on their investigations. Encourage learners to keep a journal or a log of what experiments they try. This documentation can be used to seed reflection conversations.
Arrange a collection of 20-30 different shaped hubs including circles, ovals, stars and irregular shapes on the shared work space. Encourage students to test out different combinations of hubs and directions of the motors.
You can create an arena for the machines to move around in or an obstacle course for them to traverse. Take them to different surfaces around your school and see how they work on different surfaces.
This activity can lead into further art, science and technology experiences like scribbling machines developed by the Tinkering Studio team and even be a low threshold entry point to programming with arduino or microbit to make dancing robots or twisted turtles.
Let us know if you use the Motion Machines in your educational environment. We're looking forward to see how this idea can be adapted and remixed for different settings.
Prototyping time and R&D with Lodestar Charter School students for these Motion Machines was made possible through the generous support of Cognizant “Making the Future” grant.