News Article

Flywheel-Based Attitude Control System
Date: Mar 11, 2002
Source: MDA ( click here to go to the source)

Featured firm in this article: Quoin International Inc of Carson City, NV



Summary:
Quoin International, Inc. (Carson City, NV), is developing a flywheel-based attitude control device to replace conventional stabilizing thruster technology in missiles and satellites. Miniature turbine and flywheel technologies developed for the attitude-control device have been incorporated into Quoin's PowerQuick™ Personal Lifting Device, a lightweight ascender that allows people to scale vertical surfaces quickly, safely, and inexpensively using standard climbing equipment. Two versions of the electric ascender, PQ-300-1 and PQ-500-1, are currently for sale under a subsidiary named Bonanza Products, Inc.

Technology Description:
Quoin is developing a flywheel-based attitude control system (ACS) for missiles that will be 70-percent lighter and 80-percent cheaper than conventional stabilizing technology. The device uses the theory of gyroscopic force to induce torque in the missile. This torque can be applied in the x, y, or z axes (depending on the location of the missile's target) to control pitch, yaw, and roll. In the device, a miniature turbine will be used to spin an array of small flywheels at over 100,000 revolutions per minute (RPM)—up to 500,000 RPM during stress testing. Gimbals move this device along tracks to induce the required torque.

Currently, flywheels used in satellites are prone to saturation, the point at which so much torque has been applied to the flywheel (from prolonged corrections) that it reaches a gimbal limit, saturates, and cannot influence attitude control any longer. Quoin's attitude-control device will eliminate saturation. Using a flywheel for attitude control has other advantages as well. For example, the propulsion system could be shut down, providing quieter, more precise angular control. Using the flywheel with an integrated alternator would allow electricity to be generated without the weight, heat, and reliability issues associated with thermal batteries.

A miniature compressed-gas turbine was developed as a starter mechanism for the attitude-control device's flywheels. The turbine converts the energy of a compressed gas into rotational mechanical energy. It is made up of a series of stages having a set of rotating and stationary blades, like fan blades, inside a cylinder. Compressed gas is input to one end of the cylinder where, due to the shape of the turbine, it expands and moves through the cylinder, moving the blades. The gas then flows through a set of stationary blades which direct the expanding gas deeper into the cylinder and into the next stage. Each stage in the turbine is designed to squeeze a little more energy out of the gas, speeding up the rotational velocity of the turbine. Finally, at the end of the turbine, the gas is expelled at virtually atmospheric pressure and most of its energy has been converted into the spinning mechanical energy of the turbine.

Lab testing has been performed with compressed helium and nitrogen. Additional potential energy can be generated by replacing the compressed gas with a mixture of fuel and air that is combusted.

MDA Origins:
Quoin was funded with a BMDO Phase II SBIR to develop a flywheel-based attitude control device, which can replace conventional stabilizing thruster technology in missiles and satellites. Control is currently achieved through the use of divert and attitude control thrusters whose exhaust gasses decrease the sensitivity of the vehicle's infrared sensors. Quoin's technology would reduce the number of thrusters needed for attitude control, thereby restoring some IR sensitivity.

Upon completing the flywheel device for MDA, Quoin received Defense Advanced Research Projects Agency (DARPA)funding to develop the ascender technology. From the MDA project, Quoin used the same concept of hot gas spinning up a turbine to create the air- and gas-propelled ascenders. To test the devices' components and rope-handling capabilities, Quoin used a battery-powered motor in each ascender. This led to the creation of the electric ascender.

Spinoff Applications:
Lifting Device: Quoin has created air-, gas-, and electric-propelled PowerQuick Personal Lifting Devices, which are faster and safer than manual climbing. The devices control ascent and descent and run on standard climbing equipment. Unlike typical winching devices, the ascenders move along the length of a rope instead of wrapping around a capstan. Also, to ensure safety each ascender contains an integral clutching system, which engages in the event the mechanism and brake fail.

Air: The air-powered ascender is driven by 150-psi compressed air, which is squeezed through a tiny turbine. The unit weighs 10 lbs. and can lift 300 lbs. at 1 foot per second (fps). The air-powered ascender has been designed for use in flammable atmospheres. The environmental, electrical, and agricultural industries require personnel to work in potentially explosive confined spaces, such as underground tunnels and dust-filled storage areas. Quoin's air-powered ascender has no igniting capabilities. It is expected to be on the market in 2006.

Gas-Propelled Ascender: Quoin's gas-powered ascender is driven by solid-propellent gas generator cartridges and high-speed turbines. Even though the device weighs only 7 lbs., it can lift 300 lbs. at approximately 10 fps and 500 lbs. at approximately 7 fps. The prime market for the gas-powered ascender is DOD tactical applications. For example, Navy Seals could use the ascender to quickly board a vessel at sea. For special operations the unit has to be small, lightweight, and very quick (10 fps). Organizations such as the FBI and municipal special weapons and tactics teams have also expressed interest in using the gas-powered PowerQuick ascender. This ascender is also expected to be on the market in 2006.

Electric-Propelled Ascender: Quoin developed two versions of the electric-powered ascender. The PQ 300-1 weighs 14 lbs. and lifts 320 lbs. at 1.5 fps. The PQ 500-1 weighs 11 lbs. and lifts 500 lbs at 1 fps. Both versions of the electric ascender are explosion proof and can be used in confined spaces like the air-powered model.

Although it began as proof-of-concept hardware, the electric-powered ascender is generating interest among many commercial industries and the military. Quoin is negotiating selling the product to oil companies where workers can use the ascenders to navigate oil rigs. The device will be particularly helpful for emergency egress in the event of a fire. The conventional framework of ropes and pulleys—similar to a roped elevator system—costs about $27,000. This is being replaced by Quoin's electric-powered ascender, which costs about $5,000.

The U.S. Air Force has also issued a contract to Quoin to develop a self-extracting pilot access tripod to be used in conjunction with an electric ascender. The device will be used to train personnel to rescue pilots from the F-22 stealth aircraft without wear and tear to the body. In the event of an actual emergency, it will also enable emergency personnel to evacuate the pilot from a plane in 3 minutes.

The Air Force is also evaluating the use of electric ascenders in aircraft hangars. Currently, large scissor trucks provide access to the rafters, but the planes must be removed before the scissor trucks can get inside. The ascenders can provide easy, safe, and convenient access to the rafters without emptying the hangar.

Attitude Control: This technology could be used in missiles developed by other military organizations. It could also be used in space for stabilization applications (e.g., solar panels). When coupled with the miniature gas-fired turbine, the attitude-control device could possibly be configured with sensor devices for use as an autonomous probe for deep space exploration.

Power: The miniature turbine could be incorporated into a free-piston-based micro-engine that could eventually replace batteries found in consumer products ranging from motorized bikes to industrial power drills. The engine will use propane, butane, or diesel fuel to produce a continuous stream of highly pressurized air that spins a turbine. Flywheels and actuators can be connected to the engine's drive train to generate electrical power and mechanical energy, respectively. Energy conversion efficiencies are in the range of 60 to 70 percent, which is very high for an internal combustion engine.

In another application, Quoin's free-piston-based micro-engine could be used in a lightweight engine to power a high-pressure water pump. Currently, the wildfire industry uses a bulky 2-stroke internal combustion engine for water pumping. Due to new environmental regulations, this engine can no longer be sold in new equipment and must be replaced with cleaner burning engines in the near future. Quoin's technology will enable a manufacturer to significantly reduce the weight and extend the operating life of a new engine.

Commercialization:
Quoin is selling two versions of the electric-powered PowerQuick ascenders and expects to have the air- and gas-powered devices on the market in 2006. The company is marketing the ascenders under a subsidiary named Bonanza Products, Inc. Currently, Quoins' customers include oil companies, the Air Force, and DOD special operations units.

Quoin also has joint development agreements with a large power-tool manufacturer and a water pump engine manufacturer. The company is looking for other industry partners to further develop and commercialize its attitude-control and PowerQuick technologies.

Company Profile:
Founded in 1990, Quoin is a privately held company specializing in technology engineering, development, and manufacturing. The company provides engineering services to government clients and manufactures and sells the PowerQuick ascenders and FireQuick flare systems. The company employs about 25 people.