ICRA 2011 kicks off in less than two weeks in Shanghai, China. Unfortunately, I won't be attending -- I'll have to wait to see y'all at IROS 2011 in San Francisco come September. However, I was browsing through the program and it looks like there are going to be a lot of great talks! A few that caught my eye: Morgan Quigley's low-cost 7 degree-of-freedom (7-DoF) series elastic actuator (SEA) arm for sub-$5k, Aaron Dollar's helicopter-mounted shape deposition manufacturing (SDM) hand, and Rollin' Justin's fast reflexes to catch flying (tossed) balls... and these are just the talks that have videos posted online already (embedded below). Eventually I'll get around to writing about all this cool research (after finishing my dissertation in a few months!) -- but for the time being, here's a quick scatter-shot overview.
Morgan will unveil his recent efforts to build "A Low-Cost Compliant 7-DOF Robotic Manipulator" [PDF]. The total bill of materials (BOM) comes to just $4135, which places it squarely in the range of the oft-discussed Heartland Robotics (future) offering. From the video description:
Stanford University has developed a low-cost, 7-degree-of-freedom robotic arm. The arm is made from lasercut plywood, and is powered by four stepper motors in the base and three small dynamixel servo motors in the lower arm. It is series-elastic so it is compliant if you push on it. This is done via rubber tubes that get squished between two plates, as can be seen in the video. The arm is also human-safe because it is pretty light, in addition to the compliance. The teleoperation scheme is done using a shirt with sensors in it (accelerometers and magnetometers) that detect the wearer's pose. The computer the solves for the location of the wearer's hand, and inverse kinematics are used to get the robot's gripper to track that location. The robot is running the Robot Operating System (ROS). Made by Morgan Quigley, Alan Asbeck, and Andrew Ng.
The thing that intrigues me most about this arm (aside from the cost!) is the clever design of the series elastic element.
Recall that Aaron won a MIT Tech Review (TR) 35 Award for his SDM hand. At ICRA, Aaron and crew from the Yale Grab Lab will be presenting recent work where they mount the (same?) hand on the underbelly of a helicopter for compliant grasping. The compliance (naturally) provides some benefits for underactuated grasping, but it also has a nice side-benefit for this application: the compliance helps prevent undesired forces / torques that could induce helicopter instabilities. They explain:
This work is being presented at two conference sessions:
Presumably other underactuated grippers, ie. the Jamming "Coffee Grounds" Gripper, may be good for this sort of helicopter-based manipulation?
The guys at DLR always produce impressive controllers and robots. Rollin' Justin is no exception -- we've covered him on Hizook before (plus here and here). Well, Justin has learned a new trick: "Catching Flying Balls and Preparing Coffee: Humanoid Rollin’Justin Performs Dynamic and Sensitive Tasks." This latest work is an extension of material presented at IROS 2010 in a paper titled, "Kinematically Optimal Catching a Flying Ball with a Hand-Arm-System" [PDF]. Yep... so now Justin can catch balls tossed in his direction -- perfect for a nice game of "catch." We caught a draft video posted by one of the authors:
There are going to be lots of other great research talks at ICRA. Be sure to let me know if you find one that is particularly captivating!