ARTiS:

An Adaptive Robotic Gripper for Enhanced Tool Manipulation in Disassembly Applications

Roman Mykhailyshyn1,2, Yukiyasu Domae2, Kensuke Harada1,2
1Department of Systems Innovation, The University of Osaka, Osaka 560-8531, Japan
2Embodied AI Research Team, National Institute of Advanced Industrial Science and Technology (AIST), Koto City, Tokyo 135-0064, Japan
Under Review
Paper Hardware Tutorial Purchase List CAD Files Code

Abstract

Grasping and holding tools while using them presents a considerable challenge not only for robots but also for humans. Such a challenge is particularly noticeable in processes involving assembly and disassembly, where efficiency and consistency depend on performing rapidly adaptive tasks. Nonetheless, contemporary robotic grasping technologies that can securely manipulate tools during operation frequently have significant constraints. In this paper, we introduce ARTiS (Adaptive Robotic Tool Gripper in Disassembly Systems), a novel gripper that combines the adaptability of soft grippers, the dexterity of anthropomorphic hands, and the robustness of rigid mechanisms with a soft palm. This unique combination makes it possible to hold tools securely in a variety of situations through using active jamming in the palm and fin-ray adaptation in fingertips. Furthermore, high finger dexterity is achieved through the seven degrees of freedom design, which enables the fingertips to orient themselves to any surface, both for automated solutions and collaborative tasks. We conducted a comprehensive evaluation using a range of conventional disassembly tools to assess the gripper's compliance, durability, and functional versatility.

Human Hand Bio-Inspiration

An important element in the development of the ARTiS gripping device is bio-inspiration from the human hand.
Adaptability/Motion of Human Palm and Finger
Palm and Finger

Main Methods of Grasping/Holding Studying Tools
Grasping Methods

Design Concept

To provide ARTiS with a wide working range of palm usage, it is necessary for the gripper's fingers to completely leave the working area of the jamming part (Open finger), and for this, we used the classic four-bar finger mechanism with two finger tips (Tip 1 and 2). Thanks to classical kinematics, we can solve the system of equations to find the position of the fingertip depending on the angle of rotation of the driven (motor 3 - Dynamixel MX-28R) link L1. Each gripper finger is equipped with an orientation motor (motor 2 - Dynamixel MX-28R) that changes the orientation of the finger around the finger-axis J_1 in the range from -90 to 90 degrees. One of the fingers is fixed to the base of the gripper, and the other two are driven by motor (motor 1 - Dynamixel MX-64R), which, through a double gear transmission (1:4), transmits movement to rotary platforms 1 and 2. The rotary platforms are driven to symmetrically change the orientation of the fingers relative to the gripper axis from 0 to 70 degrees. With this design, one finger has 2 DoF, and the other two have 3 DoF, which is enough to provide versatility in choosing a grasping finger configuration.
CAD_Design

ARTiS control flow
CAD_Design1

Design Specification
Spec

Highly Adaptive Fingertips

To obtain high adaptability to different tool and part geometries, we developed the novel TPU-95A 3D-printed fingertips 1 and 2. The design was bioinspired by human fingers in their ability to actively adapt to the orientation and geometry of the tools. To ensure minimal force for adapting to the tool's geometry and changing orientation, it was decided to make one of the two fixing parts of the Fin-Ray move freely (released) and combine four such structures to obtain a round shape. As a result, we got Tip 1, which consists of a rigid holder with a bolt to which four TPU-95A 3D printing elements are attached, and are additionally connected to each other with a rubber ring. The same time, we designed Tip 2, which has oppositely deployed small Fin-Rays with five elements, connected by a thin (0.3 mm) ellipse, and like the previous finger, covered with a friction surface.
Power Sphere Using Tip 1
Tip 1
Power Wrap Using Tip 2
Tip 2

Evaluating Robustness

The robustness of the ARTiS gripping device is ensured by the adaptability and force absorption of fingertip 1 (sphere holding) and 2 (wrap holding). An experimental setup was built, consisting of a fixed adaptive tip on which objects are pressed at different orientations (from 0 to 50 degrees) while simultaneously obtaining data on displacement and force. To ensure the reliability and robustness of the obtained data, each experiment is performed 30 times, and the average value is displayed with the data fluctuation zone of the same color.

Experimental Setup

Setup 2
Tip 1 Object Orienation
Tip 1 rob
Tip 2 Object Orienation
Tip 2 rob 1
Tip 2 Finger Orienation
Tip 2 rob 2
When using a tool held by a gripper, the robustness and stability of its holding are important, which are disturbed by interaction with the external environment. The most unfavorable moment occurred when grasping the power sphere method with two fingers, the force applied to the tip of the tool is directed perpendicular to the grasping plane with two fingers. Using this method, we hold screwdrivers that, with sufficient applied force, can slip out of the fingers and cause the inability to work correctly. To demonstrate the influence of the method of holding the tool with a gripper on the slipping force, an experiment was conducted according to the scheme and with two screwdrivers of different shapes and sizes when gripping (each method test was repeated 30 times to obtain an average force value): using only fingers - Finger(on); the palm is present but excluded, only fingers actively use - Palm(off), Finger(on); with the use of the palm to actively fix the tool and without the use of fingers - Palm(on), Finger(off); with the use of the palm to actively fix the tool and with the use of fingers - Palm(on), Finger(on).
Slip Diagram
Tip 1 rob
Slip Force Screwdriwer №2
Tip 2 rob 1
Slip Force Screwdriwer №4
Tip 2 rob 2

Tools Used in Assembly and Disassembly

Grasping Versatility

To test the ability of ARTiS to grasp and hold various tools (versatility) during disassembly, we selected three of the most widely used tools: a screwdriver (9 types), a hammer (2 types) and a drill (2 types). Compared to other tests for object grasping for pick-and-place operations, during disassembly, it is important not only whether the grasping is successful but also whether it is possible to reorient/use the tool and then release it in the original location. To do this, we attached an ARTiS gripping device with a control box to a collaborative 6 DoF robot arm UR-5e, which is installed 45 degrees to the worktable to which the tool holders are attached. The precise grasping consists of fixing the tool handle in the jamming palm and grasping the other end of the tool with fingertip 1. First stage is jamming, the fingers are fully opened, then moving vertically downwards the palm is deformed to the shape of the tool and reaching the maximum depth, air is sucked out of the palm, which increases the density of the palm and fixes the tool. Subsequently, the palm is lifted together with the fixed tool, and in the process, the fingers begin to close and fix the other part of the tool with the help of fingertip 1. After full grasping, depending on the need, the tool can be reoriented by changing the orientation of the fingers, or the tool can be used directly. Consequently, the tool is released in reverse order of the grasping process. In the case of power grasping, everything happens identically to precise grasping, fingertip 2 is used, and the tool is located on the table, not in the tool holder.

Jamming + Lifting

Grasping + Releasing

Grasping + Reor. + Releasing
Using Screwdriver №2
Using Drill №2
Scoring Table for Grasping Assessment

Failing Screwdriver №3

Failing Screwdriver №8

Failing Drill №1
Torque During Tightening

Torque During Tightening a Screw
Torque During Unscrewing

Torque During Unscrewing
Torque During Drilling
Torque During Drilling

Task Versatility


Collaborative Usage
Collaborative usage of a gripping device ARTiS, in this case for fixing (to ensure stability of position and orientation) a part of the mechanism during disassembly: (0) - demonstration of the problem of part movement during interaction with a human; (1) - positioning the ARTiS palm on the surface of the part, pressing it against the table; (2) - correction of the position of the fingers relative to the gripper axis; (3) - correcting the orientation of the fingers relative to the finger axis; (4) - using palm jamming and finger clamping to fix the part; (5) - human work on unscrewing screws with a fixed part.


Breaking Parts
An important task during disassembly is to break the connections and parts of the structure to speed up the process. Using the power grasping/holding tools like a human, we can break the connections of parts, in our example, the composite connection of the car's air conditioner.

Power Sphere and Wrap Holding the Studying Tools by ARTiS

A portion of the instruments holding by ARTiS using two methods is presented.

Acknowledgment

The authors thank New Energy and Industrial Technology Development Organization (NEDO) Exploratory Research Program and Denso Robotics for their support of this project.

Torque During Tightening a Screw
Torque During Unscrewing
Torque During Drilling
Torque During Drilling

ARTiS

@misc{mykhailyshyn2025artis,
	title = {ARTiS: An Adaptive Robotic Gripper for Enhanced Tool Manipulation in Disassembly Applications},
	url = {http://arxiv.org/abs/},
	doi = {10.0/arXiv.},
	publisher = {arXiv},
	author = {Roman, Mykhailyshyn and Domae, Yukiyasu and Kensuke, Harada},
	month = dec,
	year = {2025}}