This page contains a Flash digital edition of a book.
TECH FRONT THE LATEST RESEARCH AND DEVELOPMENT NEWS IN MANUFACTURING AND TECHNOLOGY t MIT 3D Prints Hydraulic Robots, No Assembly Required R


esearchers at MIT’s Computer Science and Artifi cial Intelligence Laboratory (CSAIL) present a new tech- nique for 3D printing robots that involves printing solid and liquid materials concurrently. This method allows the team to print hydraulic robots using a commercial 3D printer with no assembly required. “Our approach, which we call ‘printable hydraulics,’ is a step towards the rapid fabrication of functional machines,” says CSAIL Director Daniela Rus, who oversaw the project and co-wrote the paper. “All you have to do is stick in a battery and motor, and you have a robot that can practically walk right out of the printer.”


team also demonstrated they could 3D print a gear pump that can produce continuous fl uid fl ow.) Aside from its motor and power supply, every component is printed in a single step with no assembly required. While the hexapod’s 22-hour print time is relatively short for its complexity, researchers say that future advances in hardware would improve speed. With “printable hydraulics,” an inkjet printer deposits individual droplets of material that are each 20 to 30 μm in diameter, or less than half the width of a human hair. The printer proceeds layer-by-layer from the bottom up. For each layer, the printer deposits different materials in different parts, and then uses high-intensity UV light to solidify all of the materials (minus, of course, the liquids).


This 3D-printed hexapod robot moves via a single motor, which spins a crankshaft that pumps fl uid to the robot’s legs.


To demonstrate the concept, researchers printed a six-


legged robot that can crawl via 12 hydraulic pumps embed- ded within its body. The hexapod robot weighs roughly 1.5 lb (0.675 kg) and is less than 6" (150-mm) long. To move, a single DC motor spins a crankshaft that pumps fl uid to the robot’s legs. Among the robot’s key parts are several “bel- lows” that are 3D-printed directly into its body. To propel the robot, the bellows use fl uid pressure that is then translated into a mechanical force. (As an alternative to the bellows, the


“Inkjet printing lets us have eight differ- ent print-heads deposit different materials adjacent to one another, all at the same time,” says co-author Robert MacCurdy. “It gives us very fi ne control of material placement, which is what allows us to print complex, pre-fi lled fl uidic channels.” Another challenge with 3D printing liquids is that they often interfere with the droplets that are supposed to solidify. To handle that issue, the team printed dozens of test geometries with different orienta- tions to determine the proper resolutions for printing solids and liquids together. While it’s a painstaking process, Mac- Curdy says that printing both liquids and


solids is even more diffi cult with other 3D printing methods, such as fused-deposition modeling and laser-sintering. “As far as I’m concerned,” he says, “inkjet-printing is cur-


rently the best way to print multiple materials.” The paper, recently accepted to this summer’s IEEE


International Conference on Robotics and Automa- tion (ICRA), was co-written by PhD candidate Robert Katzschmann, as well as Harvard University undergraduate Youbin Kim.


June 2016 | AdvancedManufacturing.org 27


Photo courtesy Robert MacCurdy/MIT CSAIL


Page 1  |  Page 2  |  Page 3  |  Page 4  |  Page 5  |  Page 6  |  Page 7  |  Page 8  |  Page 9  |  Page 10  |  Page 11  |  Page 12  |  Page 13  |  Page 14  |  Page 15  |  Page 16  |  Page 17  |  Page 18  |  Page 19  |  Page 20  |  Page 21  |  Page 22  |  Page 23  |  Page 24  |  Page 25  |  Page 26  |  Page 27  |  Page 28  |  Page 29  |  Page 30  |  Page 31  |  Page 32  |  Page 33  |  Page 34  |  Page 35  |  Page 36  |  Page 37  |  Page 38  |  Page 39  |  Page 40  |  Page 41  |  Page 42  |  Page 43  |  Page 44  |  Page 45  |  Page 46  |  Page 47  |  Page 48  |  Page 49  |  Page 50  |  Page 51  |  Page 52  |  Page 53  |  Page 54  |  Page 55  |  Page 56  |  Page 57  |  Page 58  |  Page 59  |  Page 60  |  Page 61  |  Page 62  |  Page 63  |  Page 64  |  Page 65  |  Page 66  |  Page 67  |  Page 68  |  Page 69  |  Page 70  |  Page 71  |  Page 72  |  Page 73  |  Page 74  |  Page 75  |  Page 76  |  Page 77  |  Page 78  |  Page 79  |  Page 80  |  Page 81  |  Page 82  |  Page 83  |  Page 84  |  Page 85  |  Page 86  |  Page 87  |  Page 88  |  Page 89  |  Page 90  |  Page 91  |  Page 92  |  Page 93  |  Page 94  |  Page 95  |  Page 96  |  Page 97  |  Page 98  |  Page 99  |  Page 100  |  Page 101  |  Page 102  |  Page 103  |  Page 104  |  Page 105  |  Page 106  |  Page 107  |  Page 108  |  Page 109  |  Page 110  |  Page 111  |  Page 112  |  Page 113  |  Page 114  |  Page 115  |  Page 116  |  Page 117  |  Page 118  |  Page 119  |  Page 120  |  Page 121  |  Page 122  |  Page 123  |  Page 124  |  Page 125  |  Page 126  |  Page 127  |  Page 128  |  Page 129  |  Page 130