Team 5 - Gripper

Awab A., Borna M., Param O., Aman D.

EGR 557

Dr. Daniel Aukes

Developing a Research Question

Research Question

Can a mechanically-actuated (non-metallic) foldable mechanism be used as a gripper,

have as much holding torque as a soft pneumatic gripper?

Tractability

The design is inspired by the BYU oriceps design [1]. The constraints revolve around the

optimization of mechanical components for creating a state of equilibrium. While in this

state, a small force in either direction can shift the balance and moment of the system.

The goal is to prototype this mechanism with the least cost. Current estimation is that

the ﬁnal product would cost less than $30. To make the project feasible we plan on

using widely available materials such as PLA, ABS, PTEG, laminates for the body of the

gripper. Mechanical parts such as springs or fasteners may be used to strengthen the

joints on the gripper.

The gripper mechanism is constructed of electro-mechanical components that help

with the actuation of foldable mechanisms. Since pneumatic actuators utilize pressure

differences to create torque, this mechanism needs to incorporate external components

to increase the translated torque within its kinematic motion. Components such as

springs, silicon parts for creating tension, 3D printed bodies, and laminate links help us

substitute pneumatics with torsional mechanisms.

Novelty

Keywords:

● Forceps

● Origami

● Robot Gripper

● Foldable

● Kirigami

● Medical

Highly Cited Sources:

1. An Origami-Inspired Monolithic Soft Gripper Based on Geometric Design

Method [2]:

Soft end-effectors have great potential with many applications due to their

capabilities while maintaining simplicity, the speed with fabrication time, and low

cost of production. This journal focuses on combining origami with 3D printed

soft robotics to develop a gripper that is able to form around the object it intends

to grab. Two tests are performed to test the grippers capability and the research

demonstrates the gripping capabilities with daily objects.

2. Oriceps: Origami-Inspired Forceps [3]:

This paper talks about the development of a monolithic forcep that can be used

for minimally invasive surgery. Current forceps are challenging to manufacture

due to their complexity and size and can also be diﬃcult to maintain due to the

nature of their use. Hence, there is a use for tools that are inexpensive, scalable,

and require less maintenance. The oriceps are created using a single planar

sheet of material and a single input force is used to create the clamping motion.

The main design objectives that were ﬁnalized were mechanical advantage,

material suitability, product scalability, and mechanism stiffness. This design can

be manufactured at a large scale and be used in applications on the micro and

macro scales. Potential future work includes considering smart materials in the

design and how they can be applied.

3. Mechanically Programmed Miniature Origami Grippers [4]:

This paper focuses on the development of a new adjustable gripper that uses a

single actuator input for one degree of freedom motion. The gripper itself is

developed from a laser cut of a laminate fold. This mechanism works based on a

transfer function that determines the range of motion of the gripper. The

mechanism implements torsional springs to release the grip. Tendons attached to

a motor shaft translate the rotary motion to linear motion of the gripper ends. The

tension on the tendons, the torsion of the spring, and the dimension of the folds

determine the kinematic properties in the mechanism.

4. A 3D printable Robotic Gripper Based on Thick Panel Origami [5]:

This paper focuses on the development of an origami gripper based on the

kinematics of thick panel origami. The gripper was designed to make the

experimental kinematics more accurate because normal origami gripper motions

are not too accurate, so the gripper uses a water bomb origami design in which 4

legs are used to maximize the gripping strength. The thickness of the legs also

further reduce the degrees of freedom of the overall gripper and thereby reduce

the wear and tear normal origami grippers face due to their high level of degrees

of freedom and complex kinematics. The gripper used four 3d printed TPU legs

and was tested on symmetrical and asymmetrical materials, and the

experimental results were accurate with analytical results.

Interesting

The question is important because such a gripper can be used in many different ﬁelds

and create a greater impact in the ﬁeld. The question is important now because of the

greater dependence on human and robot interaction to achieve common goals. The

advancement in technology has allowed humans to enhance their capabilities to

achieve different tasks in ﬁelds such as medicine and space exploration. Such

human-robot interaction was not present 10 years ago, thus, there was no need for a

solution to this problem. A delicate yet strong gripper is needed to complete certain

tasks with precision. Furthermore, being lightweight and modular, such a gripper should

eliminate unnecessary costs and encourage similar actuation methods. For the general

public, an inexpensive gripper could be used to generate interest in the masses and

used for educational purposes, while ensuring the safety of the users.

Open-Ended

Yes, the question remains open-ended as it allows researchers to discuss multiple

possibilities to achieve the goal. Further research could include methods to make the

design stronger, better actuated, and more modular to ﬁt in multiple ﬁelds. Provided

enough time and resources, better actuation methods and materials can be tested and

compared to make the design more lightweight, stronger, and designed for different

applications. The research question is structured in a way that allows us to investigate

various mechanisms and methods without being limited to certain mechanisms or

techniques.

Modular

Yes, the question is modular because the gripper could be made into one part of a larger

project, a lightweight robot arm that is strong while using foldable robotics techniques.

There are a wide number of ﬁelds in which such devices could be used, for example,

space applications could beneﬁt greatly from a lightweight robot arm/gripper that is

able to carry heavy-weight objects while being gentle and able to handle delicate or

fragile objects.

Team Fit

Mechanical mechanisms are a common topic of interest among all team members.

Some team members are very skilled with mechanical mechanisms, while others have

experience with folding mechanisms and origami. We believe that combining the skills

with fabrication techniques we gain from the class could lead to a successful project

that functions as intended.

Topic Fit

The question looks to explore origami-inspired mechanisms to actuate a gripper. While

the team plans on using springs to aid the gripper, the gripper will be strictly a

mechanical mechanism made out of materials and techniques commonly used in

foldable robotics, such as laminates, plastics, and 3D printed parts.

Citations

[1] “Origami inspires tiny medical devices - youtube.” [Online]. Available:

https://www.youtube.com/watch?v=L_9BDZ6ZBwk. [Accessed: 07-Feb-2022].

[2] Z. Kan, Y. Zhang, Y. Yang, Y. A. Tse and M. Y. Wang, "An Origami-Inspired Monolithic

Soft Gripper Based on Geometric Design Method," 2019 2nd IEEE International

Conference on Soft Robotics (RoboSoft), 2019, pp. 470-476, doi:

10.1109/ROBOSOFT.2019.8722746.

[3] B. J. Edmondson, L. A. Bowen, C. L. Grames, S. P. Magleby, L. L. Howell, and T. C.

Bateman, “Oriceps: Origami-inspired forceps,” Volume 1: Development and

Characterization of Multifunctional Materials; Modeling, Simulation and Control of

Adaptive Systems; Integrated System Design and Implementation, 2013.

[4] Orlofsky, C. Liu, S. Kamrava, A. Vaziri and S. M. Felton, "Mechanically Programmed

Miniature Origami Grippers," 2020 IEEE International Conference on Robotics and

Automation (ICRA), 2020, pp. 2872-2878, doi: 10.1109/ICRA40945.2020.9196545.

[5] C. Liu, P. Maiolino, and Z. You, “A 3D-printable robotic gripper based on thick panel

origami,” Frontiers in Robotics and AI, vol. 8, 2021.