Soft robots, primarily made out of intrinsically soft materials, have flourished greatly in the past decade due to their advantages such as flexibility and adaptability over rigid-bodied robots. A rich repertoire of soft robots designed from intuitive or biomimetic approaches have been developed to provide new solutions for robots. However, these design approaches are limited by the designers' experience and inspiration, and a systematic design methodology for soft robots is still missing. We tackle this issue by mathematically recasting the design problem under the framework of topology optimization problem. To demonstrate the effectiveness of the proposed methodology, in this paper, we develop a pneumatically actuated soft gripper consisting of three fingers, each finger is able to undergo a free travel bending and deliver a grasping force. Hence, each gripper finger is designed as a continuum compliant mechanism to achieve its maximal bending deformation. The proposed soft gripper with complex shape is directly fabricated through 3D printing technology. Experimental results show that the deflected soft finger is able to achieve a 41° free travel bending and generate 0.68N blocked force upon 0.11MPa actuation pressure. This work represents an important step towards the goal of designing soft robots automatically.

Most spaceborne sensors have a tradeoff between high spatial and high temporal resolutions. This tradeoff limits the use of remote sensing data in various applications that require images in both the high spatial and high temporal resolutions. In this paper, we propose a novel technique to create a fine spatial and high temporal resolution images at a ground-based data processing system. Resourcesat-2 is one of the Indian Space Research Organization missions, and it carries the Linear Imaging Self-Scanning sensors (LISS III and LISS IV) and an Advanced Wide-Field Sensor (AWiFS) onboard. The spatial resolution of LISS III is 23.5 m, and that of AWiFS is 56 m. The temporal resolution of LISS III is 24 days, and that of AWiFS is five days. The proposed method creates a synthetic LISS-III image at 23.5-m spatial and five-day temporal resolutions. It is based on the subpixel relationship between a single AWiFS–LISS-III image pair, which is acquired before or after the prediction date. In temporal data composition, spurious spatial discontinuities are inevitable for land-cover type changes. These discontinuities were identified with temporal edge primitives and were smoothed with a spatial-profile-averaging method. A synthetic LISS-III image for time$t_{k}$is predicted from an AWiFS image at time$t_{k}$and a single AWiFS–LISS-III image pair at time$t_{0}$, where$t_{0}\ne t_{k}$. Experimental results demonstrated that the proposed method is superior in terms of the computational efficiency and prediction accuracy with the other existing methods.

Distributed collaborative design and manufacture enables manufacturing organizations to seamlessly collaborate with each other to design and manufacture products with shorter lead time. This requires the distributed system not only to maintain data consistency across globally distributed locations seamlessly, but also allows team members to access the services securely and transparently. In addition, appropriate information models need to be developed to facilitate design data exchange between different domains. This paper reports on the development of a distributed collaborative system by addressing the above issues and demonstrating the developed system using fixture design and analysis as a case study. Web services and service-oriented architecture (SOA) are employed in this system to address the issues of interoperability, platform-independence, and language neutrality. Information exchange models based on XML schema have been used to facilitate data transfer between design and analysis.

The recently launched IRS-P6 satellite has a unique capability of acquiring simultaneously multispectral data at three different spatial resolutions from three independent optical sensors (LISS-4, LISS-3 and AWIFS). Of these, the LISS-4 sensor can be operated in two modes: (i) multispectral (MX) mode covering a swath of 23 km and (ii) monochromatic (MO) mode covering a 70-km swath, both at a spatial resolution of 5 m. One of the important uses of the LISS-4 MO data is in realizing a 5 m band-sharpened multispectral image by merging it with the low-resolution LISS-3 MS image. Operationally anyone of the three LISS-4 bands can be chosen for the MO mode data acquisition. The performance of each band for producing band-sharpened MS images is evaluated, and the choice of the band based on the spatial and spectral characteristics of the merged data is suggested. The LISS-4 Red-band is found to be optimal. It provides band-sharpened imagery with spatial and spectral qualities very similar to the LISS-4 MX data products.

Fixture design is an important manufacturing activity which affects the quality of parts produced. In order to develop a viable computer-aided fixturing tool, the fixture-workpiece system has to be accurately modeled and analyzed. This paper describes the modeling, analysis, and verification of optimal fixturing configurations by the methods of force closure, optimization, and finite-element modeling (FEM). Force closure has been employed to find optimal clamping positions and sequencing, while optimization is used for determining the minimum clamping forces required to balance the cutting forces. The developed FEM is able to determine in detail what are the reaction forces, workpiece displacement, deformation in the workpiece and fixtures. In order to produce a more accurate model for predicting the behavior of the fixture-workpiece system, the developed FEM includes fixture stiffness, which past models have assumed as rigid bodies. The reaction forces on the locators are experimentally verified. A sensor-embedded experimental fixturing setup was developed to verify the modeling and the data was used to compare with the FEM. Note to Practitioners-In practice, the machinist applies excessive force to hold the part on machine table, so that it does not move when machining is carried out. However, while machining flexible parts or clamping on finished surfaces, care must be taken so that only necessary and optimal clamping forces are applied, to avoid deforming the part or damaging the surface. Therefore, in this study, we have developed a mathematical model to characterize the mechanics and conditions for a fixture to hold a given part. The developed mathematical model computes the optimal clamping forces required to hold the part in position, given the cutting conditions. The result obtained was verified by conducting the machining test using the developed sensor-embedded experimental fixture setup. The FEM was also developed to predict the behavior of fixture-workpiece system and the results obtained were encouraging.

The use of fuzzy integral (FI) for combining an ensemble of neural networks is proposed for multispectral data classification. The FI is further employed for integrating original data with its smoothed version. In both cases, the FI combine is found to be superior to that of their individual classification performance.