A gripper with two thumbs! 🐨 Handheld data collection is how a lot of manipulation datasets get built now. Someone picks up a gripper-shaped device, does the task by hand, and the recording becomes training data. Voila! 🤌🏼 The catch is that these devices are usually shaped to match whatever robot gripper already exists. The human ends up working around the robot's morphology, which costs both ergonomics and the quality of the demonstration being recorded. The @rai_inst team designed The Koala Gripper. It includes two devices with full parity: a capture device a person holds, and a robotic device that executes the learned policy. Anything you can do with one, the other reproduces. The shared feature set gets updated as the design iterates, so neither side quietly compromises the other. The morphology is where it gets interesting. Two independently controlled underactuated fingers are opposed by a single pivoting "dual thumb", which is where the koala name comes from. → Each finger is a 9-bar linkage with one actuated and one underactuated degree of freedom, with the spring sitting proximal to the phalanges to drive preshaping → Fingernails on the distal link for precise pinches, contoured pads for secure wrap grasps → The handheld trigger traces a natural fingertip arc instead of a straight line, lengthening the stroke and giving the operator better mechanical advantage → On the robot side, a frameless motor with an integrated high-pitch ballscrew keeps reflected inertia low, so the fingers stay backdrivable at an effective mass of tens of grams The dual thumb is what buys tool stabilising, singulating one object out of a pile, and tabletop pinches. Congrats to @zubinbot and the RAI Institute team behind it 👏🏼 🔗 Project page: ~~ ♻️ Join the weekly robotics newsletter, and never miss any news →