science

Pathfinder Technology Demonstrator

Pathfinder Technology Demonstrator is a science topic covered in the lgStudy science library. This page brings together a partial reference excerpt, illustrations, worked examples, real-world applications and a short study plan, so you can understand Pathfinder Technology Demonstrator rather than just read about it. In short: NASA's Pathfinder Technology Demonstrator (PTD) Project is a series of tech demonstrations of technologies aboard a series of nanosatellites known as CubeSats, providing significant enhancements to the performance of these versatile spacecraft. Each of the five planned PTD missions consist of a 6-unit (6U) CubeSat with expandable solar arrays.

Key takeaways

Pathfinder Technology Demonstrator belongs to science; place it in that map before memorising details.
Learn the definition first, then one example that makes the definition concrete.
Connect Pathfinder Technology Demonstrator to a quantity you can measure, compute or draw — that is where exam questions come from.
Reproduce the core statement of Pathfinder Technology Demonstrator from memory before moving on to harder problems.

Reference excerpt

NASA's Pathfinder Technology Demonstrator (PTD) Project is a series of tech demonstrations of technologies aboard a series of nanosatellites known as CubeSats, providing significant enhancements to the performance of these versatile spacecraft. Each of the five planned PTD missions consist of a 6-unit (6U) CubeSat with expandable solar arrays. Flight qualification and demonstration of these technologies carried aboard the PTD missions are expected to benefit future government and commercial missions. These include propulsion systems and sub-systems that stabilize and point the spacecraft to high accuracy in order to use a laser communications system capable of high-speed broadband. The first mission, PTD-1, was scheduled for launch in December 2020 on a Falcon 9 rocket, from Cape Canaveral, as part of the ride-share ELaNa mission 35, launched on January 24th, 2021, and demonstrated HYDROS-C water-based propellant system. PTD-3 launched on May 25 2022 on the SpaceX Transporter-5 rideshare and demonstrated the TBIRD infrared communication system.

Overview The Pathfinder Technology Demonstrator (PTD) Project is led by NASA's Ames Research Center in California, in collaboration with NASA's Glenn Research Center in Ohio. The PTD project is managed and funded by NASA's Small Spacecraft Technology Program (SSTP) within the Space Technology Mission Directorate. The overall goal is to test the physics of key new technologies in order to enhance small spacecraft and make them able to reach new destinations and operate in new environments. These technologies will be tested in low Earth orbit for potential future application in small spacecraft operating in Earth orbit or in deep space. Technologies demonstrated by PTD flights may be applicable and scalable to larger spacecraft. The project plans to fly five 6U CubeSat orbital missions, coded PTD-1 through PTD-5, at 6-month intervals, each flight assessing different technologies. Each mission will have a 90-day lifetime after it is released in low Earth orbit. Each spacecraft will include different test payloads such as propulsion systems for orbital station-keeping, maneuvering and interplanetary transit, laser high bandwidth communications, or high precision attitude control (orientation) systems to stabilize the spacecraft and point the designated instruments with high accuracy.

Technology under assessment Examples of novel systems to be tested are an electrospray thruster, water-based propulsion, and a very precise attitude control system.

BET-100 μN is a colloid thruster fabricated by Busek that was successfully flown in the ESA LISA Pathfinder mission in 2016. Each thruster requires less than 6 watts of power. Attitude Determination and Control System (ADCS), uses Blue Canyon's Hyper-XACT ADCS. The package incorporates a star tracker, 3-4 reaction wheels, three torque rods, a magnetometer, an inertial measurement unit, and up to four Sun sensors. HYDROS is a hybrid chemical/electrical technology to provide propulsion using water. It uses an electrolysis cell to split water propellant into gaseous hydrogen and oxygen that are stored under pressure in separate tanks for burning in a thruster nozzle. This propulsion system is being developed by Tethers Unlimited, Inc. The MPS-130 engine by Aerojet Rocketdyne burns a novel ionic liquid propellant called hydroxylammonium nitrate (NH3OHNO3). It is a fuel/oxidizer blend also known as AF-M315E that is about 50% more efficient than traditional hydrazine, and is non-toxic. Aerojet Rocketdyne tested this engine and fuel on a mission called Green Propellant Infusion Mission, launched aboard a SpaceX Falcon Heavy rocket on 25 June 2019, on a test mission called Space Test Program 2. The PTD project will also evaluate the commercial Globalstar communications network for low cost in-space communications for sending commands to spacecraft in low Earth orbit. Each of the five planned spacecraft will incorporate a Globalstar GSP-1720 Duplex Modem.

PTD-1 A Request for Proposal (RFP) NNA16574335R was issued, on 12 February 2016, for the delivery of a spaceflight qualified 6U CubeSat spacecraft to be operated by NASA for its Pathfinder Technology Demonstrator (PTD) Project to accommodate technology subsystems, hereafter referred to as the payload. One flight demonstration is planned for a low thrust propulsion system with options for four follow-on technology demonstrations. Follow‐on missions may include payloads such as higher thrust propulsion systems or payloads such as optical communications or high precision attitude determination and control systems. Request for proposal response date: 4 April 2016. The PTD-1 spacecraft is currently under development and fabrication. It will demonstrate a propulsion system with a water-based propellant obtained from electrolysis of water. While in orbit, the system separates onboard water into hydrogen and oxygen propellants by applying an electric current through the water. PTD-1 is scheduled for launch in December 2020 as part of the ride-share ELaNa mission 35 on board a Falcon 9 rocket. PTD-1 launched January 24th 2021 on SpaceX rideshare Transporter-1 mission.

HYDROS Propulsion test

HYDROS is a hybrid chemical/electrical technology to provide propulsion using water. It uses an electrolysis cell to split water propellant into gaseous hydrogen and oxygen that are stored under pressure in separate tanks. The system then burns the hydrogen and oxygen mix in a simple thruster nozzle to provide up to 1 Newton and a specific impulse of 258 seconds. This propulsion system is being developed by Tethers Unlimited, Inc. In pure water, at the negatively charged cathode, a reduction reaction takes place, with electrons (e−) from the cathode being given to hydrogen cations to form hydrogen gas. The half reaction, balanced with acid, is:

Reduction at cathode: 2 H+ (Aqueous solution) + 2e− → H2 (gas) At the positively charged anode, an oxidation reaction occurs, generating oxygen gas and giving electrons to the anode to complete the circuit:

Oxidation at anode: 2 H2O (liquid) → O2 (gas) + 4 H+ (aqueous solution) + 4e− Overall reaction: 2 H2O (liquid) → 2 H2 (gas) + O2 (gas) The propulsion system uses the electricity generated by the solar arrays to power the miniature water electrolysis. The demonstration will test propulsion performance through programmed changes in spacecraft velocity and altitude.

… excerpt ends here. Continue reading the full article.

Worked examples

Example 1 — a first encounter with Pathfinder Technology Demonstrator

Start with the simplest possible case. Write down what Pathfinder Technology Demonstrator claims or describes in one sentence, then invent the smallest concrete situation in which that sentence is true. In science, the smallest case is usually a single object, a single equation or a single measurement. Check that every symbol or term in your sentence has a meaning in that case.

Example 2 — changing one variable

Take the situation from Example 1 and change exactly one quantity: double it, halve it, or set it to zero. Predict what should happen to Pathfinder Technology Demonstrator before you calculate. Comparing your prediction with the result is the fastest way to find out whether you understand the idea or only the words.

Example 3 — an exam-style question

Typical questions about Pathfinder Technology Demonstrator ask you to (a) state it precisely, (b) apply it to given data, and (c) explain a limitation. Practise writing all three answers in under five minutes; the third part is what separates a full-mark answer from an average one.

Applications of Pathfinder Technology Demonstrator

In research: Pathfinder Technology Demonstrator appears in science research whenever the underlying quantities have to be modelled precisely. Papers usually cite it as a starting assumption and then explore where it breaks down.
In technology and industry: Engineering practice reuses Pathfinder Technology Demonstrator in design rules, simulations and safety margins. Knowing the idea lets you read a specification sheet and understand why the numbers look the way they do.
In the classroom: Pathfinder Technology Demonstrator is common in secondary-school and first-year university syllabi. It links to neighbouring topics CubeSats, Future SpaceX commercial payloads, Laser communication in space, so understanding it makes those chapters shorter.
In everyday life: Look for Pathfinder Technology Demonstrator outside the textbook — in sport, cooking, traffic, electronics or the sky above you. An example you found yourself is remembered far longer than one you were given.

Affiliate

Preply — study more efficiently by working with a personal tutor. 50% off.

How to study Pathfinder Technology Demonstrator in 20 minutes

Read the reference excerpt below once, without taking notes.
Close the page and write down what Pathfinder Technology Demonstrator means in your own words.
Compare your version with the excerpt and mark what you missed.
Work through the three examples above with pen and paper.
Explain Pathfinder Technology Demonstrator out loud to somebody else — or to Teacher Smith in the lgStudy chat.

Frequently asked questions

What is Pathfinder Technology Demonstrator in simple terms?

Why does Pathfinder Technology Demonstrator matter?

Because it connects several science ideas at once: it gives you a definition you can apply, a quantity you can calculate, and a way to check whether a result is plausible.

How should I study Pathfinder Technology Demonstrator?

Read the excerpt, restate it from memory, then work through the examples and applications listed on this page. The five-step study plan above takes about twenty minutes.

What does this page cover?

It gives you a compact reference excerpt plus original lgStudy explanations, examples, applications and study material on Pathfinder Technology Demonstrator.