Mr. Ballenger has over 14 years diversified embedded and computer related engineering experience. Most of his career is software engineering for application and embedded systems. He has provided technical leadership for teams of engineers developing complex commercial and defense products, and he has worked on leading edge research projects where he was a principle contributor. His areas of expertise include software engineering, real-time systems, and user interfaces.
He has been involved in the development of a wide variety of commercial and defense projects ranging from missile defense to stage lighting to biofeedback. He has been a guest speaker at MIT, Software Engineering Institute, Carnegie-Mellon University and various industry conferences. His experience covers real-time embedded software applications including digital signal processors, computer graphic and image processing, graphical and embedded user interfaces, serial communications, communication protocols, simulation, and real-time scheduling analysis.
Mr. Ballenger has received awards for his development effort of Wybron's Autopilot, which was awarded Product of the Year by the lighting industry 2 times in the same year.
Currently with SIGNALWARE, Mr. Ballenger is developing real-time embedded and PC software, and device drivers for new digital signal processor applications.
Developed windows software for the data collection, communication, and PCB production test of the Remote Sensing System (RSS) propane and fuel monitoring system. The system consists of up to six solar powered transmitters that are installed on propane/fuel tanks, and a controller that receives and processes the 903 MHz RF signal. The controller calls into the data collection center on a schedule/alarm basis to report fuel levels. RSS enables propane and fuel distributors to optimize tank refills, and provides daily monitoring of customer systems in case of an alarm condition.
Developed data collection and communication software, which receives calls from the remote customer sites via a 2400 Kbaud fast connect modem and updates an Oracle database. The automated system provides self diagnostics, and automatically resolves any local server problems. The software provides system diagnostic status on the RSS web site, to ease system administration.
Developed PCB production test software, which performs a series of automated tests using an analog and digital data acquisition board. The software probes test points on the transmitter and controller PCBs using a bed-of-nails fixture. The transmitter PCB tests consist of power and solar cell circuitry voltage measurement, RF frequency tuning with a frequency analyzer, and hall sensor calibration for the fuel sensor. The controller tests consist of RSSI adjustment, FM discriminator adjustment, and modem integrity testing with a central office simulator.
The Remote Sensing System is in production and servicing propane/fuel customers in the United States. The system is in proposal for other monitoring markets.
Developed signal processing and windows Graphical User Interface (GUI) software for the Bodyscan EMG Biofeedback system. The Bodyscan system monitors electrical characteristics of the patient's response to sensory stimulus. 33 Hz and 8 kHz sampling rates are considered for a spectral analysis of 8 chakra energy frequencies. Analysis results are graphically displayed to the user for symptom diagnosis. Data is stored for later retrieval and comparison.
The Bodyscan EMG Biofeedback system is currently in development and test.
Principal software developer for the Autopilot automated spotlight tracking and control system. Autopilot is an innovative system that enables concert and production venues to provide an automated spotlight system to follow up to 4 performers with any of 24 spotlights in real-time. The system utilizes a thunder and lightning approach with infrared and ultra-sonic transmitters and receivers to locate a performer within the desired area. Once located, the system points a camera, moving mirror or moving head spotlight at the performer. Autopilot has advanced features of auto sizing and focus of the spotlight beam, user defined zones with automatic cross-fades and dimming at boundaries, and a smoothing sphere around the performer.
The performer being tracked carries a transponder device that sends out coded signals to fixed receivers. Position of the transponder is computed from the delays in the transmitted signal by statistical filtering of the time series data. The technology employed includes Kalman Filters, non-linear least squares approximation, and vector algebra with measurement error sensitivity considerations. The Autopilot system consists of a TMS320C31 and 18 other microprocessors (PIC, 8051, and 68HC11) programmed mostly in C. The user interface consists of a handheld with a 45 button keypad and 4x24 character LCD.
Autopilot received both of the lighting industries Product of the Year awards from Plasa and LDI. Autopilot is currently in production and used in several traveling concert tours and fixed installations.
Principal software developer for Advertising In Motion (AIM) back-lit scrolling billboard. AIM enables merchants to display multiple image frames in a single advertising space. AIM utilizes an embedded closed loop control solution with 2 servo motors. One motor pulls the image frames onto a roller while the other motor provides rolling tension by pulse width modulation of the back electromagnetic force from the drive roller. The motors switch functionality to reverse the image frames back to the other roller. AIM is configured by a 4 button and 16-character LED user interface. The interface was designed to perform complex configuration and display settings in an intuitive manner.
Developed AIM software for reuse and easy configuration for different motors and frame sizes. AIM has been adapted to a variety of unique indoor and outdoor settings. McDonalds has integrated AIM into their menu in a test market. Copper Mountain has integrated a customized outdoor unit into their mountain trail maps and message boards at the base and peak. The outdoors AIM is integrated into a self-contained environmentally controlled enclosure that stabilizes the temperature for optimal operation.
Principal software developer and system architect for the ColoRAM and Watchdog stage lighting system, consisting of a centralized power supply, communication protocol, network interface, and various stage lighting peripherals, including scrolling color changers, dowsers, gobo (goes before optics) effects, and projectors. Additionally the ColoRAM system is monitored remotely by Watchdog.
Developed the ColoRAM Power Supply, which provides power and a RS485 communications network interface to the distributed peripherals. The power supply's embedded system allows for plug and play of peripherals with real-time control and status reporting. A standard lighting console provides the input control signal of 512 independent channels. The power supply manages and distributes the control signal to each peripheral and queries them for health and status. The power supply reports peripheral status to Watchdog, a monitoring system.
Developed 11 different ColoRAM peripherals, consisting of scrolling color changers (ColoRAM II, CXI, and AquaRAM), dowsers (Eclipse), gobo effects (GoboRAM), and projectors (Proscenia). All peripherals are embedded closed loop servo or stepper motor control implementations. Each peripheral maintains controlled position of media and reports health and status back to the power supply via the RS485 interface. Peripherals are configured with assorted switch and button/display user interfaces.
Developed the Watchdog system, which consists of an embedded communication interface to the ColoRAM power supply and a windows based Graphical User Interface (GUI). The embedded processor assembles real-time health and status information for all devices on the network, including multiple power supplies, and transmits the information to a PC over an RS232 interface. The GUI displays the peripheral health and status information in real-time to the user in an intuitive format that can be accessed by point and click of peripheral icons and dialogs.
The ColoRAM system is used in virtually all traveling concerts and productions, and many fixed installations.
Principal developer of PerfoRMAx, a windows based real-time scheduling analysis tool. PerfoRMAx enables developers to identify and predict the timeliness and schedulability of a real-time system before, during, and after implementation using the principles of Rate Monotonic Analysis (RMA). RMA mathematically guarantees deterministic timing prediction of a fixed priority, preemptive, real-time system.
Performed research and development in the area of fixed priority, preemptive real-time scheduling analysis techniques. Worked in conjunction with the Software Engineering Institute to advance the theory of RMA, and assist in technology transfer to industry.
Developed a windows schedulability engine and Graphical User Interface (GUI). The schedulability engine performs RMA calculations, identifies scheduling errors, and suggests scheduling resolutions. The GUI is used to characterize the real-time system through a series of wizards and task identification tables. The GUI also displays RMA results in graphs and timeliness. The GUI intuitively displays preemption, blocking, and priority inversion terms to the user for further insight and analysis.
PerfoRMAx is currently bundled with Aonix ObjectAda Real-time development suite and used by industry leaders such as NASA and Boeing in order to build the software systems for the International Space Station.
Developed concepts, graphical displays, requirements, algorithms, and software for a real-time distributed Ballistic Missile Defense Command and Control simulation. The simulation implemented a variety of missile defense solutions including ground and space based radars, interceptors and lasers. The simulation enabled US Space Command to exercise the command structure in a variety of configurations and scenarios.
Contributed insightful solutions to unique software and algorithm problems. Provided technical leadership and development support to the software engineering team in rapid prototyping C and FORTRAN environment for the Cray 4mp. Interfaced with customer to address modifications to architecture, graphical displays, operations concept, and fidelity of simulation.
Produced object-oriented design and model for a real-time distributed satellite communication network emulator, and developed Ada prototype simulation software to support proof of concept.
Performed implementation and hardware/software integration of Digital Imagery Workstation Suite (DIWS) for the US Navy. DIWS is a real-time distributed image processing and graphics workstation used for cruise missile mission planning. The workstation uses stereo satellite imagery to display a 3-dimensional scene for user navigation and rendering. The workstation combines graphics rendering with seasonal, foliage, probability of instability and verticality, and other components to determine the usability of terrain features and target areas in order to determine a flight update match feasibility.
The DIWS system is implemented in Ada according to 2167A. Developed and implemented advanced algorithms for analyzing and enhancing digital imagery. Integrated the distributed real-time Ada application across a VAX host and an embedded Motorola 68020 and Mercury Array Processor VME subsystem.