2.5 - Research: Weeding Out a Solution

In this activity you will address the following scenario:

A UAS is to be designed for precision crop-dusting. In the middle of the design process, the system is found to be overweight.

• Two subsystems – 1) Guidance, Navigation & Control [flying correctly] and 2) Payload delivery [spraying correctly] have attempted to save costs by purchasing off-the-shelf hardware, rather than a custom design, resulting in both going over their originally allotted weight budgets. Each team has suggested that the OTHER team reduce weight to compensate.
• The UAS will not be able to carry sufficient weight to spread the specified (Marketing has already talked this up to customers) amount of fertilizer over the specified area without cutting into the fuel margin. The safety engineers are uncomfortable with the idea of changing the fuel margin at all.

Write a response describing how you, as the Systems Engineer, would go about resolving this issue. Use your imagination, and try to capture what you would really do. Take into account and express in your writing the things you’ve learned so far in this module: What are your considerations? What are your priorities? What do you think about the future prospects for the “next generation, enhanced” version of the system as a result of your approach?

Weeding Out a Solution

Considerations

            As the systems engineer, I have been confronted with resolving the issue of determining how to reduce weight on an unmanned aerial system (UAS) designed for precision crop-dusting. Two teams, guidance, navigation & control, and payload delivery have both attempted to save costs by purchasing off the shelf hardware. Both teams have gone over the allotted weight budget and both teams have suggested the other team reduce weight. As the systems engineer, it is important to be unbiased and knowledgeable about each person’s individual job in order to avoid further conflicts during the design process of the unmanned aerial vehicle (UAV).

            The customer must be a consideration and a priority. How will customers react to the delayed schedule of the UAV? With the UAV being overweight and the marketing team discussing the spread capabilities of the UAV to customers, it could be necessary to lower the price of the UAV due to the UAV being less capable than what the company has already stated to customers. The customers are expecting to be able to purchase the UAV by a specific date. It would not look good on the business if the delivery date of the UAV was changed. However, it may be necessary considering the UAV would be less capable than what the marketing team has stated.

            One of the first steps I would take would be to review the lifecycle process technical review of phases and control gates. This process is setup to stop designers and manufacturers from continuing the development of a UAV unless a review has been completed (Terwilliger, Burgess, & Hernandez, 2013). By utilizing a phase-gate approach to the development of this UAV, and completing a corresponding review of each step in development, it is likely that the issue of the UAV being overweight would not have occurred in the first place. I would want to determine what parts were causing the UAV to become overweight. Even though the project is already over its allotted budget, it may be beneficial to create custom designs for hardware in order to reduce the weight of the UAV. The off the shelf hardware may be a critical factor in the issue of the UAV being overweight. It would be necessary to determine if custom designs for hardware would reduce the weight of the UAV.

Priorities

            The main priority in this scenario is to determine how to reduce the weight of the UAV while also keeping the customers happy with the design since the marketing team has already discussed the capabilities of the UAV. Taking the fuel margins into consideration, and under the recommendation of the safety engineers, the fuel levels should not be adjusted. It could be hazardous for people on the ground if the UAV has a short flight life. It would also be appropriate to have the guidance, navigation, & control team work their way back through the design process to determine if there is a more efficient design that would reduce the weight of the UAV. There is a chance that the team could look for more guidance, navigation, and control components that are lightweight and efficient enough for the operation of the UAV. Since the team used off the shelf components, these components may have not been as lightweight as aerospace grade materials. As far as communication with the teams goes, it would be beneficial to determine whether the teams were using a requirements-based design process described by Howard Loewen (2013). UAV manufacturing processes can be incredibly complex and highly structured. “As the UAVs produced become more sophisticated ad-hoc design processes become insufficient. Presently, more UAV manufacturers than ever have come to realize structured design processes are essential if they intend to develop reliable products” (Loewen, 2013, pg. 1). A requirements-based design process is a thorough methodology that helps UAV manufacturers address concerns and issues during the designing process for UAVs.

            Since the marketing team has already been talking to customers about the spread of the fertilizer, it is important to consider how customers would react if the product did not spread fertilizer as well as the marketing team specified. The profits from the UAV could be incredibly limited if customers purchase the UAV and determine that it does not spread the fertilizer as efficiently as the marketing team specified. As the system engineer, I would recommend the payload delivery team go back to the early stages of the design process and determine if custom designed hardware would reduce the weight of the UAV. Keeping the customers happy is a critical component of the well-being of the business. If the customers believe the marketing team has lied, word will spread and fewer customers will come back to purchase the next generation of the UAV from the business. I would suggest that the payload team redesign the fertilizer delivery system. If the delivery system had a wider spread, the UAV would require fewer laps around a field while dispensing the fertilizer. With fewer laps over a field, flight times should be shorter and fuel should be conserved. With better fuel consumption, the safety engineers will be satisfied. If aerospace grade materials are used by the navigation, guidance, and control team, the weight of the UAV could be reduced.

Future prospects for the next generation of the system

            With the first generation being overweight, the second generation of the UAV cannot have the same design flaws. The teams must collaborate in a more efficient manner; using the requirements based design process should prevent problems from occurring like they have with the first generation. As the systems engineer, I will act as the “great decider” and ensure each design team is communicating with the other teams so the chance for miscommunication is limited. If each team communicates properly, every person will be able to weigh in on solutions to keep the UAV within design limitations. With the issue of the first generation being overweight, the designers of the next generation should increase the acceptable weight loads of the UAV. Custom designed hardware should be considered before using off the shelf hardware. Payload levels should be increased and the marketing team should collaborate with the design team to prevent any misleading information from being spread to potential customers. If the first generation cannot be redesigned to meet the needs of the customer, the price of the next generation could be adjusted as compensation for the first generation not being within specified design requirements. I would also suggest that the allotted budget for the UAV be increased if possible in order to compensate for the purchase of the required materials. 

References

Loewen , H. (2013). Requirements, based UAV design process explained. Retrieved from             https://www.micropilot.com/pdf/requirements-based-uav.pdf

Terwilliger, B., Burgess, S., Hernandez D. (2013). ASCI 530 unmanned systems: Global system   design concepts, requirements, and specifications overview [PowerPoint Slides]. 

1.5 Assignment Research: History of UAS

History of UAS

Introduction

            Unmanned aerial vehicles have been around for a number of years. UAVs have been a powerful tool in the military and the civilian sector. During World War I, UAVs were used to perform missions over the Western Front in 1917 and 1918 (Blom, 2010). The missions that were conducted using UAVs are similar to the missions seen in Iraq and Afghanistan in modern times. According to Blom (2010), UAVs in the past and present have been used to adjust indirect fires, gather information regarding enemy movement, perform battle damage assessment, and provide target acquisition. In 1955, the United States Army started performing reconnaissance missions with UAVs; the Radioplane RP-71 was one of the UAVs tested during this time. As technology has advanced, UAVs have become a big part of the military and are being used more in the civilian sector. UAVs have many different purposes within the world today. From reconnaissance and damage assessments in the military to photography and disaster assessments, UAVs will become a huge part of the aviation industry in the coming years. The RQ-7 Shadow 200 is a relatively new UAV being utilized by the military.

Radioplane RP-71 Falconer

            The Radioplane RP-71 Falconer had a wingspan of 12 feet and could ascend into the atmosphere at 3,000 feet per minute (Blom, 2010). The RP-71 could reach a top speed of 185 miles per hours and could fly at altitudes between a few hundred feet and up to 4 miles. The endurance of the RP-71 was 30 minutes according to Blom (2010).The RP-71 took several minutes to launch. A catapult launch system was used to send the RP-71 into the sky (Blom, 2010).  The RP-71 utilized a solid rocket booster from zero length launcher (Northrop Radioplane RP-71, n.d.). The RP-71 would be recovered by deploying a parachute. One benefit that the RP-71 had over traditional aircraft was that this UAV could be flown in weather that would be hazardous to other aircraft. The RP-71 had advanced technology during its conception. This UAV used cameras and had an optional TV (Northrop Radioplane RP-71, n.d.). The pictures taken by the RP-71 took some time to process, but an operator could have the pictures in under an hour (Blom, 2010). The RP-71 was also designated as MQM-57 and was a reconnaissance unmanned vehicle. An operator would fly the UAV via radio signals and was tracked by radar (USAF, 2015).

RQ-7 Shadow 200

            The RQ-7 Shadow 200 is a UAV that was developed to locate and identify targets on the battlefield. The Shadow can fly up to 15,000 feet and has a cruising speed of 127 knots (RQ-7 Shadow UAV). The Shadow is launched from a hydraulic rail launcher and has the ability to climb at a rate between 1,000 to 1,500 feet per minute (Shadow 200 RQ-7, n.d.). Compared to the RP-71, the RQ-7 can carry heavier payloads for longer periods of time. This UAV incorporates incredible electro optical and infrared sensors that give the operator the ability to capture video and pictures during the day and night (RQ-7 Shadow UAV). The RQ-7 is easily recoverable; it has a conventional landing gear and can land on a flat surface if there is a surface that is 95 meters in length. The RQ-7 Shadow is controlled through a sophisticated ground control system. The ground control station is suited with vehicle control settings and C4I interface software (Shadow 200 RQ-7, n.d.). The operating procedures for the RQ-7 had to be redesigned during US campaigns in Iraq and Afghanistan due to the intense heat and massive amounts of sand building up on the UAV (RQ-7 Shadow UAV, n.d.).

Comparison between the RP-71 and the RQ-7 Shadow 200

            The Radioplane RP-71 Falconer and the RQ- Shadow 200 are similar in purpose. The RP-71 and the RQ-7 are launched with the aid of a catapult system, but the benefit of the RQ-7 is that it can be launched without the aid of a catapult system. Both of these unmanned aerial vehicles have been used for intelligence, surveillance, and reconnaissance. Damage assessment is still completed by the RQ-7 Shadow. While the Shadow seems to have more uses overall, the RP-71 has the ability to fly at a faster rate (185 mph in the RP-71 compared to 127 in the RQ-7 Shadow) and the RP-71 can fly at higher altitudes than the RQ-7. However, the flight times are very different when comparing these two UAVs. The RP-71 could fly for 30 minutes while the RQ-7 could fly for 6 hours (RQ-7 Shadow UAV, n.d.). The RQ-7 has a technologically advanced sensor package compared to the RP-71’s radio transmission and radar contact tracking systems. Unlike the RP-71, the ground control station that is utilized by the operator of the RQ-7 provides the operator with real time footage that the cameras are picking up. The RP-71 had cameras and an optional TV, but it took some time to develop the pictures that the UAV took during flight. The advances in technology have now required operators to need more room to transport the UAVs to a specific location. The RP-71, the launcher, and the control system could be transported by two standard 6x6 trucks with trailers (Blom, 2010). A single RQ-7 can be transported by two military vehicles (Shadow 200 RQ-7, n.d.). The RP-71 had an identical wingspan of 12 feet (Blom, 2010). In comparison, the RQ-7 Shadow had a wingspan of just over 12 feet.

Conclusions

            With the advancements in technology and the creation of the RQ-7 Shadow, military operators using the Shadow are able to gather intel and perform reconnaissance missions more efficiently. There does seem to be one limitation with the RQ-7 Shadow; the top speed seems to be lacking. Compared to the RP-71, the RQ-7 is much slower (185 mph vs. 127 mph.). While speed is not necessarily always needed, it may be beneficial for the RQ-7 to fly at a faster rate. As new technology is created for UAVs such as the RQ-7, operators should determine if there are any flaws in the response times of the RQ-7 during flight. GPS has become the standard for operations around the world. GPS may not be a new technology, but any improvements on this system could potentially influence the system capabilities of the RQ-7. It is likely that military UAVs will continue to receive the latest and greatest in the area of optics for the cameras on board the RQ-7. An increase in the flight time of the RQ-7 could greatly influence the system capabilities of the RQ-7 and would be beneficial to long range reconnaissance missions.

References

Blom, J. D. (2010). Unmanned Aerial Systems: A Historical Perspective. Fort Leavenworth, KS: Combat Studies Institute Press.    

doi:http://usacac.army.mil/cac2/cgsc/carl/download/csipubs/OP37.pdf

Northrop Radioplane RP-71 Falconer, SD-l. (n.d.). Retrieved from      http://www.wmof.com/rp71falconer.html

RQ-7 Shadow UAV. (n.d.). Retrieved from http://olive-            drab.com/idphoto/id_photos_uav_rq7.php

Shadow 200 RQ-7 Tactical Unmanned Aircraft System. (n.d.). Retrieved from http://www.army-technology.com/projects/shadow200uav/

USAF. (2015). Radioplane/Northrop MQM-57 Falconer. Retrieved from             http://www.nationalmuseum.af.mil/Visit/MuseumExhibits/FactSheets/Display/tabid/509/            Article/195784/radioplanenorthrop-mqm-57-falconer.aspx