IEEE Robotics & Automation Magazine - December 2015 - 28

Promising research directions for the the future of robotics
are as follows:
● advanced design and manufacturing approaches that
aim to circumvent some of the challenges of traditional technologies
● the application of software development techniques on
electromechanical synthesis
● integrating and cogenerating all the aspects of a robot to
include mechanical, electrical, and software subsystems
● incorporating compliance in robotic development
● robots improving human lives through the unprecedented
levels of interaction, especially in medical settings.
Design of Robotic Systems
Designing a robotic system requires translating the definition
of the desired electromechanical device between various types
of specifications. The design process often starts with a functional specification describing the system's intended behavior.
The ultimate goal of design in this context is to end up with a
set of fabrication specifications that can get sent through a
manufacturing process to make a robot. This flow can be split
with an intermediate structural specification that realizes the
functionality in terms of mechanisms and assemblies.
Research into design systems for robots aims to assist users in
the creation of fabricable drawings directly from the structural or functional specifications.
Design for manufacturability (DFM) considerations
impose constraints on functional and structural specifications
based on the limits of fabrication technology. By expanding
the manufacturing capabilities, these constraints can be
relaxed or, ideally, eliminated. For example, three-dimensional (3-D) printing technology allows for nearly any rigid
body to be fabricated, thus allowing for the direct realization
of arbitrary functionally specified solid structures. It is toward
this goal that robotic design research is aimed: the ability to
make arbitrary functionally specified mechanisms.

cesses is an active area of research. Compliance in structural
elements adds another dimension to the design space, which
needs to be incorporated into the design flow. By examining
hybrid structures and composite metamaterials, Wehner et
al. [1] demonstrated how to fabricate structures with a range
of material properties, as shown in Figure 1. A related fabrication process presented by Menguc et al. [2], [3] (Figure 2)
was used to manufacture soft sensors designed using a functional specification.
Origami-Inspired Folding
In contrast to the solid objects generated by 3-D printing,
mechanical structures can instead be fabricated by folding
their surfaces from a patterned two-dimensional (2-D) sheet
in a manner similar to the Japanese art of origami. This process has been used to create robotic bodies out of sheets of
paper, plastic film, and multilayer laminates [4]-[6]. This

Microchannels
Micro

Flex
Circuitt

Soft Silicone

o
Velcro
(Undern
Stiff Silicone (Underneath)
(a)
Allignment
Features
Top Mold
oft Silicone
for Soft

Top Press
Molding Lip

Compliant Materials and Soft Robots
With an increasing emphasis on soft robotics in the community, DFM for compliant materials and manufacturing pro-

Elastomer 2

T1
Fabric
Layer

T2
i

(a)

Elastomer 1
i

(b)

(c)

Figure 1. The multimaterial designs allow structures to be
manufactured with a wide range of stiffnesses and different methods
to design and fabricate bending actuators. (a) The asymmetrical
geometry. (b) The inextensible (fabric) layer. (c) The elastomers of
different moduli. (Photo courtesy of Wehner [1].)

IEEE ROBOTICS & AUTOMATION MAGAZINE

DECEMBER 2015

Bottom Mo
Mold
for Soft Si
Silicone

ester Films
Polyester
Top Mold for
Stiff Silicone
Bottom Mold
f Stiff Silicone
Sili
for

C
Vacuum Chuck
Interface

(b)
Figure 2. The advanced manufacturing processes can realize the functional specification of a soft sensor, which calls for a range of material
properties. (a) Sensor. (b) Molds. (Photo courtesy of Menguc [3].)

Table of Contents for the Digital Edition of IEEE Robotics & Automation Magazine - December 2015