origami-inspired robot combines micrometer precision with high speed

Because of their high precision and speed, Delta robots are deployed in many industrial processes, including pick-and-place assemblies, machining, welding and food packaging. Starting with the first version developed by Reymond Clavel for a chocolate factory to quickly place chocolate pralines in their packages, Delta robots use three individually controlled and lightweight arms that guide a platform to move fast and accurately in three directions. The platform is either used as a stage, similar to the ones being used in flight simulators, or coupled to a manipulating device that can, for example, grasp, move, and release objects in prescribed patterns. Over time, robotics have designed smaller and smaller Delta robots for tasks in limited work spaces, yet shrinking them further to the millimeter scale with conventional manufacturing techniques and components has proven fruitless.

Reported in Science Robotics, a new design, the milliDelta robot, developed by Robert Wood's team at Harvard's Wyss Institute for Biologically Inspired Engineering and John A. Paulson School of Engineering and Applied Sciences (SEAS) overcomes this miniaturization challenge. By integrating their micro fabrication technique with high-performance composite materials that can incorporate flexural joints and bending actuators, the milli Delta can operate with high speed, force, and micrometer precision, which make it compatible with a range of micro manipulation tasks in manufacturing and medicine.

In 2011, inspired by pop-up books and origami, Wood's team developed a micro-fabrication approach that enables the assembly of robots from flat sheets of composite materials. Pop-up MEMS (short for "microelectromechanical systems") manufacturing has since been used for the construction of dynamic centimeter-scale machines that can simply walk away, or, as in the case of the RoboBee, can fly. In their new study, the researchers applied their approach to develop a Delta robot measuring a mere 15 mm-by-15 mm-by-20 mm.

"The physics of scaling told us that bringing down the size of Delta robots would increase their speed and acceleration, and pop-up MEMS manufacturing with its ability to use any material or combination of materials seemed an ideal way to attack this problem," said Wood, who is a Core Faculty member at the Wyss Institute and co-leader of its Bioinspired Robotics platform. Wood is also the Charles River Professor of Engineering and Applied Sciences at SEAS. "This approach also allowed us to rapidly go through a number of iterations that led us to the final milliDelta."

The milliDelta design incorporates a composite laminate structure with embedded flexural joints that approximate the more complicated joints found in large scale Delta robots. "With the help of an assembly jig, this laminate can be precisely folded into a millimeter-scale Delta robot. The milliDelta also utilizes piezoelectric actuators, which allow it to perform movements at frequencies 15 to 20 times higher than those of other currently available Delta robots," said first-author Hayley McClintock, a Wyss Institute Staff Researcher on Wood's team.

In addition, the team demonstrated that the milliDelta can operate in a workspace of about seven cubic millimeters and that it can apply forces and exhibit trajectories that, together with its high frequencies, could make it ideal for micromanipulations in industrial pick-and-place processes and microscopic surgeries such as retinal microsurgeries performed on the human eye.

Putting the milliDelta's potential for microsurgeries and other micromanipulations to a first test, the researchers explored their robot as a hand tremor-cancelling device. "We first mapped the paths that the tip of a toothpick circumscribed when held by an individual, computed those, and fed them into the milliDelta robot, which was able to match and cancel them out," said co-first author Fatma Zeynep Temel, Ph.D., a SEAS Postdoctoral Fellow in Wood's team. The researchers think that specialized milliDelta robots could either be added on to existing robotic devices, or be developed as standalone devices like, for example, platforms for the manipulation of cells in research and clinical laboratories.

"The work by Wood's team demonstrating the enhanced speed and control of their milliDelta robot at the millimeter scale opens entirely new avenues of development for industrial and medical robots, which are currently beyond the reach of existing technologies. It's yet another example of how our Bio inspired Robotics platform is leading the way into the future," said Wyss Institute Founding Director Donald Ingber, M.D., Ph.D., who is also the Judah Folkman Professor of Vascular Biology at HMS and the Vascular Biology Program at Boston Children's Hospital, as well as Professor of Bio engineering at SEAS.

SUBSTATION AUTOMATION

Abstract—Automation can easily increase the efficiency of the Industries the main aim of our concept is to monitor and control the Industrial substation by using SCADA. The power grid was previously monitored by Manual and now it can be monitor by using Internet.

 Main functions of substation automation include accurate fault location to prevent false tripping and to minimize the area affected by the fault. We can access data securely from any part of the world by point to point communication using internet. Substation automation increase reliability and performance of electrical protection, advanced disturbance and event recording capabilities is possible.

 The changes in load and stability affects the operation of a power system. The increase in power conception lead to the construction of many substations. This lead to the automation of substation for reducing the complexity of power transmission.

Keywords—RTU, Protocol, Electrical distribution, Substation automation, SCADA, KSEB.

I.  INTRODUCTION

Nowadays the electricity problems are affecting the productivity and efficiency of the industry. This can be eliminated by automating the industrial substation. Through substation automation reliability and performance of electrical protection is increased, advanced disturbance and event recording capabilities are gained.

 This system can monitor and control the circuit-breakers operated on the site, to achieve data acquisition, measurement, parameter adjustment, and various signal alarms.
 This monitoring system uses monitoring hosts to call and monitor the load status, load distribution curve, accident statistics, important alarm, working status, and other electricity monitoring data of various substations. In RTU automated substation, the power equipment, their communication and computers are interdependent. The datas from substation equipment is communicated with the SCADA systems by using RTU. 

 The main advantage of using SCADA system is that monitoring and controlling can be done easily and reduce the human labour [1]. The monitoring system and real time supervision system of the field devices and the real-time status are currents, voltages, pressures, temperatures, contacts, etc. This supervision is made through digital equipment and special sensors that are installed in the field devices of the substation. The data are collected and processed in a data acquisition and control unit (UAC), to thereafter through a communication network, using desirably a protocol standardized international sent to a central computer located at the control building of the substation and later to the operation centers and so allowing a remote supervision. Measured values reflect different time varying quantities, such as voltage, current, temperature and tap changer positions, which are collected from the power system. They fall into two basic type and digital. All analogue signals are transformed via an A/D converter to binary format because treated as momentary-value that they have to be normalized before storing [2].

 The substation automation system in a given substation had to exchange enormous information to deliver the desired performance. This required considerable customization through protocol converters that were proprietary (Manufacturer Specific) in nature, but that was not compatible with a multi-vendor environment. The SCADA applications and individual device vendors share common tag data bases. Specialized point to point link to IEDs applications must deal with numerous Protocols, Data formats & Data addressing. There is virtually no link to other applications. Communication path must be reconfigured, when new device and applications are added. The most recently widely used technology like OPC was mainly adopting this approach [3].

 It is very difficult to know the actual losses on the distribution network. Generally, rules of thumb are used to estimate the power losses [4]. 

 The basic information about the challenge for the EPS is to provide a quick response to the undesirable effects, maintaining reliability and competitive prices [5].

II.  NEED FOR SUBSTATION AUTOMATION

The basic needs for the industrial substation automation are:

Substation automation is required in Industries to increase reliability and performance of electrical protection of circuits in substation, which will affect the efficiency of power distribution.

Advanced disturbance of the power and event recording capabilities can be achieved by using RTU, which will record the amount of unit used by the industry in each sec.

Display of real time substation information is possible by using multi-function meter and SCADA, which is required for getting open access from KSEB.

Remote switching and advance supervisory control can be done easily by the output module of RTU which is connected to the coil relay for more efficiency.

The high-power EMF produced in the transformers during step up or step down of the power that is distributed through grid lines, can affect human brain cells.

Advanced automation functions like intelligent load-shedding can be done for easier, faster and safer during the power transmission time or at any short-circuit problems.

The main circuit breaker can be controlled by using internet instead of manual control which is possible by the use of RTU and the communication unit with SCADA.

The hacking of the Industrial substation or malfunctioning of it can be identified and alarm can be set for the security purpose of the power transmission.

Financial Need for Substation Automation

The factors that lead the industries in Kerala to automate their substation is explained below.

Kerala State Electricity Board Ltd (KSEB Ltd) is a public-sector agency under the Government of Kerala, India, that generates, transmits and distributes the electricity supply in the state.

Kerala State's average daily consumption is 74.77 million units per day which cannot be generated from the hydro power station alone.

Figure 1. Industrial Power Distribution Diagram

To satisfy this energy need KSEB has executed purchase of power from north region of India.

But, KSEB have to bear the transmission losses in grid line during the power distribution.

KSEB then sell this power to industries for higher unit cost which increased the profit of KSEB.

Many Industries closed in Kerala because of the high electricity bill that they need to pay.

For supporting the industries that need more units of power, the Kerala government given permission for open access.

By taking open access, the industry can directly purchase low cost power from northern power generators.

For taking open access the industry should automate their substation by using RTU and SCADA.

After implementation of this project the cost of each unit will be reduced as per the present price.

But the industry should pay maintenance charges to KSEB for transmitting power from the north through grid lines.

III.  CONCEPT MODEL

The conceptual model that we suggest for the substation automation system is given below.

 Our system is developed for controlling the main CB of the industrial substation and to collect, display and store the electrical parameters from the substation for the future reference. The present status of the substation is also transferred to the receiver through VPN connection, where the datas are safely uploaded for the KSEB control. The hacking is eliminated by using the NTP server which will update the time of the system in each sec.

The main components used for substation automation system are the MF meter, RTU, Modem, and SCADA control. The MF meter collects the electrical parameters from the industrial substation and display it and also transmit the datas to the RTU. As per the data received from the process plant the RTU will control the main circuit breaker. The RTU can be configurated by using the PC through Ethernet cable. The IP address for the SCADA controller is configurated in the RTU. Through point to point communication the substation is controlled by using the SCADA system.

IV. ASSEMBLED MODEL

The assembled substation automation model developed by us is shown below along with the various components that are marked on the figure itself.

V. WORKING

For the protection of RTU panel first Siemens MCB is connected with the power supply, then the indicator light is connected to output lines of the first MCB. SMPS switch is also connected to the output power line of first MCB to reduce 240V to 24V input power supply, then it is connected to the second MCB, then to RTU Power Module.

The current and voltage input is taken from KSEB incomer and connected to MF meter. The output from MF meter is connected to the RTU communication module. The input from ammeter and voltmeter is connected to RTU input module through solid relay. The output from key switch is connected to RTU input module. The output module of the RTU520 is connected to the Main Circuit Breaker through coil relay.

The RTU is connected to the lap through Ethernet cable, then by using RTU Utility software configuration is done. The point to point communication is developed by using BSNL ONT server and router is connected for providing Wi-Fi network.

The breaker control and substation monitoring data is transferred to KSEB SCADA controller through point to point communication. Then the KSEB officer can see the present status of the industrial substation and the data about the power usage of the industry in each second will be stored. The main circuit breaker of the industry can be controlled by using SCADA.

VI. PROFIT ANALYSIS

By automating the substation, the industries are getting many benefits. By taking open access for the electricity used by the industry the profit of the industry will increase.


The following profit analysis is done based on the approximate electricity units used by an industry.

VII. CONCLUSIONS

Substation Automation will improve routine asset management, quality of service, operational efficiency, reliability, and security.
 The three parts of the system are assimilated with the advanced communication and measurement technology. As added advantage to the existing system, the proposed methodology can monitor the operating situation, easily detect and locate the fault of the feeders and status of breakers.
 The information from the system helps in apprehending the advanced distribution operation, which includes improvement in power quality, loss detection and state estimation.
 Also can eliminate the high cost of electricity by implementing this concept in the industrial substation. A small fault in the electrical circuit may damage the entire Industry. By our concept the problems faced by the industry can be eliminated and the complete circuit protection can be achieved.

CNN Uses Vantage Robotics

CNN Uses Vantage Robotics' Snap Drone to Win FAA Fly-Over-People Waiver

By Jogi Jose

Vantage Robotics' Snap drone weighs just 620 grams and is held together with magnets, allowing it to come apart on impact.

The U.S. Federal Aviation Administration’s Small UAS Rule (also known as Part 107) has provisions to obtaining waivers to the usual requirements for flying drones in the United States. For example, you’re not generally allowed to fly drones at night, although the FAA has granted quite a few waivers allowing flight after dark.

But another rule is that you can’t fly drones over people who are not part of your operations, and until about a week ago, the FAA hadn’t waived that rule for anybody. Now it has, for CNN. The FAA is allowing the cable news network to use a drone to obtain video over uninvolved people, even crowds assembled at places like sporting events.

Clearly, the safety of folks beneath the drone was a big concern here. CNN says it was able to address the issue by using a drone called Snap from San Francisco Bay Area startup Vantage Robotics.

Most quadcopters control yaw using just the torque that develops in reaction to changes in the speed of the blades. Vantage Robotics decided to make yaw control more responsive by slightly tilting the front propellers backward and the rear propellers forward. This configuration creates thrust forces that apply a torque directly to the frame of the craft.

Snap weighs just 620 grams (1.4 pounds). And it’s held together with magnets, allowing it to come apart on impact—say, with your head—which makes it less likely to do any lasting damage. AeroVironment has been using the same strategy with hand-launched military drones—not so that they don’t do inadvertent collateral damage, but so that they don’t damage themselves during their rather hard deep-stall landings.

Another safety measure Snap includes are shrouds around its whirling blades. That’s not uncommon for drones, particularly those you might fly inside. But Vantage Robotics cleverly designed blade shrouds using “tensegrity,” a term that American inventor Buckminster Fuller coined more than half a century ago, and which refers to objects that use components in compression or tension to maintain their structure. (NASA is also using tensegrity-based designs, to build robots.) A bicycle wheel would be an example of the kind of thing that inspired Snap’s featherweight blade shrouds.

Snap has blade shrouds based on a tensegrity structure that is lightweight but strong.

Perhaps a greater innovation is the strategy Snap adopted to control yaw—movements that make the drone rotate to the left and right. Other quadcopters control yaw using just the torque that develops in reaction to changes in the speed of the blades. Two diagonally opposed blades are made to speed up, while the other two are made to slow down. The overall upward thrust is the same, but because those pairs rotate in opposite directions, the body of the drone rotates in response.

The problem is that this reaction torque doesn’t have much oomph. So it’s hard to make yaw control very responsive in drones of this type. And that was a particular problem here, because Vantage Robotics didn’t want to have to add a third axis to its camera gimbal to damp out yaw motions. So it needed to have the whole drone yaw on command swiftly and precisely. The company’s solution, according to a patent application filed last year, was to cant the propellers: The two on the front point somewhat backward; the two on the rear point somewhat forward.

Small dihedral angles of this type are often used for the wings of aircraft to add stability. In model airplanes, wing dihedral also allows the plane to bank with just rudder control. Snap’s dihedral improves yaw “authority” because when two diagonally opposed propellers spin up, their canted thrust forces apply a torque directly to the frame of the craft.

My hat’s off to the company for creating what looks to be a very benign yet capable drone. It’ll be fascinating to see what kind of video footage CNN is able to attain with it.