Tuesday, December 15, 2009

Quanser's Journey to Engineer Unmanned Vehicle Systems for Academic Advancement

Recently, Quanser introduced a completely new platform for teaching and research - the Unmanned Vehicle Systems (UVS Lab). UVS Lab is the result of more than five years of Quanser’s internal research and development efforts. To learn more about their journey, we talked with the two people driving the innovation - Dr. Jacob Apkarian, Quanser’s Founder and CTO and Cameron Fulford, Systems and Control Engineering Manager.

Jacob: Ever since I was a kid, I wanted to fly my own devices - I guess that's where it all has roots. The unmanned research at Quanser started about five years ago when we began thinking how we can use our Quarc control system design software (or WinCon at the time) to actually fly things. Quarc's real-time capabilities allowed us to collect data online, tune parameters online, so if you have any flight dynamics issues that you want to do online, you can do it right away with this rapid prototyping software. Alas, the technology to do this was not there - so we developed it! Now I feel like an ace when flying these things - something I could never do without Quarc.

Cameron: For years Quanser offered the 2 DOF Helicopter, 3 DOF Helicopter and a 3 DOF Hover, which are not flying vehicles, but experiments simulating flying vehicles. So moving towards vehicles actually flying seemed like a natural progression.

Jacob: As engineers at Quanser started to look into the area, we realized there are a lot of people doing research in unmanned autonomous vehicles. We approached the Defense Research and Development Canada (DRDC), where we found Dr. Camille-Alain Rabbath, a scientist who supported this kind of research. We started to collaborate with DRDC on development of the vehicle control systems, but we still did not have any vehicles. We came up with the ALTAV - an almost lighter than air blimp, because we thought it would be easier to fly than something that is heavier than air.

Cameron: The first version of ALTAV had a shape of a round beach ball, which we eventually replaced with 11 and 13' long, more traditional blimp-looking shape. These ALTAV versions were all helium-filled blimp balloons with 4 actuated motors, so you could actually tilt the motors and get a vectored thrust, controlling the direction of the thrust of each motor. That was a novelty behind the design of our ALTAV vehicle.

One of Quanser's ALTAV models with its design and engineering team

Jacob: On our journey we learnt that a vehicle with four motors is a good design. As we continued our research, we discovered a lot about the IMU needed, and the sensors needed to fly these things properly. So as the time went by, we started developing the ultimate IMU board, which we now call the HiQ. From there our software engineers enhanced Quarc to generate code for the HiQ and control any vehicle. However as we started flying the ALTAV outside, we quickly realized the challenges: one of them being legal issues, because you have to get all the licenses and permits to fly outside. The other challenge was the weather.

Cameron: The ALTAV was so large that it was susceptible to winds. If there was any matter of wind, it could really affect the performance of that vehicle, so it was difficult to fly outdoors, but at the same time, was too big to fly indoors. A lot of people we are talking to ultimately want to do test flights outdoors, but they can begin their research indoors. We needed something smaller that can fly inside and is safe. Indoor lab space is available all year round, the conditions are the same, so it’s much better especially at the initial stages of research.

Jacob: People are doing research in control systems and the control systems can be implemented indoors and outdoors, it does not matter. That is why we started developing what we call the indoor Unmanned Vehicle Systems Lab.

Cameron: We wanted to create a framework for controlling multiple vehicles, the mission development framework. That’s how the Quanser vehicle abstraction layer (VAL) started – a mechanism for developing multi-agent missions and doing high-level vehicle control. We also investigated and developed a number of different vehicles, including quadrotors, Zagi fixed wing, and these were all flown outdoors. Basically due to the reasons Jacob mentioned - environmental factors and the legal restrictions, we started developing the UVS Lab, which is the concept for indoor lab, for doing unmanned vehicle research. Each vehicle is pretty individual in terms how it works. At the higher level, controlling the mission is something that we learned to do through all of the vehicles we investigated and created. Now we can apply what we learned and developed to the newest vehicles that are being released for use by academics.

The newest vehicles we developed were the Qbot, an unmanned ground vehicle and the Qball-X4, a quadrotor UAV designed for flying indoors. The flexibility of these vehicles and the lab setup provide researchers a lot of potential to develop complex missions with even more vehicles, without compromising on safety. With an aerial vehicle like the Qball-X4 there is a higher likelihood of collisions, either with another vehicle or a wall, safety was a big concern. So we decided to build a vehicle that has a built-in cage to protect it and protect the users. We added OptiTrack support for localization purposes, since you no longer have the GPS. As part of our development, the HiQ Aero Data Acquisition card also had to go through many changes. We now have a brand new HiQ that was re-designed from the ground up for these new vehicles. In fact, the Qball-X4 has a completely new HiQ with the on-board Gumstix computer that runs Quarc, Quanser's real-time control software. Throughout all these vehicles the Gumstix has been the main computer on-board. As the Gumstix technology continues to improve, Quanser's unmanned vehicles will feature more powerful on-board computers. While we accomplished a lot in the last five years, Quanser's journey to give the academics a reliable and robust UVS platform has only began.

Quanser's new Qball-X4 quadrotor

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