Robots in the military

Brave, autonomous, and dispensable warriors

BY JIM DAVIS
Cypress Semiconductor
San Jose, CA
http://www.cypress.com

The use of robots in war dates back to World War II with the German Goliath remote-controlled explosive vehicles and the Soviet Union’s wirelessly controlled, unmanned Teletanks. In today’s military conflicts, the airspace is filled with unmanned aerial vehicles of all sizes—from the hand-launched vehicles of the Special Forces to the jet-powered Predator drones flown by Airmen thousands of miles away from the conflict area; as well as ground-based autonomous and wirelessly controlled robotic vehicles for high-risk patrols to explosive ordinance detonation and disarming. These robotic vehicles support a variety of military missions ranging from covert intelligence gathering to direct support to ground forces and overt military strikes. And we’ve just scratched the surface.

The military robotic force of today saves lives. As designers and engineers of robotic systems and components, you may or may not even know that you play a large part in enabling these and future systems.

Developing these systems, however, is not a trivial task. Robotic systems, in their most basic form, simulate or otherwise artificially sense their environment and, through programmed logic, respond and interact with their surroundings.

They are the ultimate mix of analog sensing, driving and digital logic, processing, and communications. Mixed-signal designs are definitely not new, but with state-of-the-art advances in the fundamental components that make up these designs, there are now ways to implement robotic subsystems easier, with lower power requirements and at greatly reduced cost.

Interacting with the real world is inherently analog. A robotic system’s ability to not only accurately sense its surroundings but to do so with high resolution provides the system a stream of data inputs to more effectively enable correct decision-making and response. For example, to enable a robotic sentry to effectively protect a perimeter, the system must be able to monitor and detect movement — be it through sight, sound, or touch.

Through the use of a combination of high-precision thermal, IR, ultrasonic, and/or optic analog sensors the raw input of what the robot can see can be streamed into a programmable movement detection algorithm to measure the change between snapshots and processed for the decision-making process — effectively an analog-to-digital conversion. The response itself is also an analog process (that is, a robot interacting with its environment requires movement, motors, and motor control), effectively a digital-to-analog conversion.

Fig. 1. Design tools help define the signal path and configure components at the sytem-level. As shown, an ADC is generated based on parameters, such as desired resolution, sample rate, and voltage reference source.

The brain of the robotic system lies within the digital domain. Based on the converted analog signals, the preprogrammed logical steps of responding to those signals are carried out by the robotic brain and/or externally communicated commands to the robot. In the robotic sentry example, after the detection algorithm feeds an alert to this brain, a series of preprogrammed logical functions are executed to steadily increase the robot’s overall alert state by executing intimidation actions to thwart the intruder into retreating via flood lights, verbal warnings, etc.

Historically, designs engineered for systems like a robotic sentry required sensors, costly analog discrete ADCs, amplifiers, highly accurate voltage references, DACs, PWMs, and multiple processors and microcontrollers. These are just the components that make up the individual sense-detect-decide-respond-report subsystem, just one of many functions a robotic sentry would be responsible for.

The challenge to you in implementing just this one function is the selection of the right analog discrete components (ADCs, amps, Vrefs, DACs, etc.) designed for or compatible with the selected high-precision sensors as well as the digital components, processors, and even potentially the custom logic gates to build the alarm-level state machine to enable the appropriate decision and response. Not only is this a complicated and challenging task, but should any part of this require redefinition—perhaps swapping a sensor, adding additional sensors, adding additional response mechanisms, etc. — the same complicated task must be repeated all over again. Finally, the large number of discrete components also quickly adds up in total subsystem BOM cost and increases power requirements, a double whammy due to just the number of components.

This is where the state-of-the-art programmable, mixed-signal system-on-chip devices can ease this burden. Take, for example, Cypress’s PSoC programmable system-on-chip architecture and software tool, PSoC Creator. Through the integration of an analog, digital, logic, and processing core into a single mixed-signal device, designers can realize system cost savings while greatly improving the power budget.

Systems-level programmability in both the analog and digital domains in these types of devices also eases the often difficult and time-consuming analog design process, as well as the ability to rapidly prototype, test and, without even having to re-layout designs, change and incrementally update the design along the way. For example, with systems-level programmability, tools designed at this level of design present you with a method of defining the signal chain in a mixed-signal device and the ability to modify that same signal flow as the design progresses. It becomes possible to define the signal path and configure the components at the system-level such as the ADC itself using parameters such as desired resolution, sample rates, voltage reference sources, etc., all without having to consult an analog component data book (see Fig. 1 ).

Design tools for mixed-signal system-on-chip devices allow designers to define the signal path and configure components at the system-level. For example, the PSoC Creator dialogue shown here generates an ADC based on parameters such as desired resolution, sample rate, and voltage reference source.

The military robot is a brave and autonomous warrior and, unlike its human counterpart on the battlefield, can be a dispensable asset that protects those it serves. Through the use of state-of-the-art, programmable mixed-signal technologies, engineers can further evolve these robotic warriors with greater ease and power/cost budgets, freeing designers to apply more time and effort on the thing that matter most: the robot’s core mission. ■