Polhemus Patriot
Polhemus Patriot is a line of electromagnetic 3D tracking systems by Polhemus. It has an update rate of 60Hz.
Patriot sensors operate in the millivolt range.
The transmitters for Patriot are compatible with other Polhemus systems: the FasTrak, FastSCAN, and Liberty.
The patriot is available in a special form factor for mounting inside a desktop PC case, called the Patriot DB. DB stands for "Drive Bay" as it mounts in a 5.25" drive bay of a computer.
Patriot was first announced in 2004.[1]
There is a version 2.0 of Patriot known as High Speed Patriot.
Patriot has first-party USB drivers for Windows and Linux, and a GUI application called PiMgr that runs on Windows.
Versions[edit]
- Patriot
- Patriot High-speed
- Patriot M, for medical settings
Connection[edit]
USB[edit]
The Patriot's USB vendor ID is 0f44. The original Patriot's device ID may be ef11 or ef12. It is ef12 when the firmware has been loaded.[2]
For a Patriot high-speed unit, the device ID may be ef20 or ef21.
RS-232[edit]
Patriot requires a null modem cable.
Operation[edit]
ASCII characters are sent over USB or RS-232 from the computer to control the SEU. The following is a list, with the decimal number and the hexadecimal after each:
- A Alignment Reference Frame 65 0x41
- B Boresight 66 0x42
- C Continuous Print Output 67 0x43
- F Output Format 70 0x46, note: 0=ascii, 1=binary, for example F0 or F1
- G Source Mounting Frame 71 0x47
- H Hemisphere of Operation 72 0x48
- L Stylus Button Function 76 0x4C
- N Tip Offsets 78 0x4E
- O Output Data List 79 0x4F
- P Single Data Record Output 80 0x50
- Q FrameCount/Timestamp Reset 81 0x51,note: 0=both;1=FC,2=TS
- U Set Units 85 0x55, note: 0=inch, 1=cm
- X Position Filter Parameters 88 0x58
- Y Attitude Filter Parameters 89 0x59
- control-B UN-Boresight 2 0x02
- control-E Set Echo Mode 5 0x05, note: 0=off, 1=on
- control-K Save Operational Configuration 11 0x0B
- control-O RS-232 Port Configuration 15 0x0F
- control-R Reset Alignment Frame 18 0x12
- control-T Built-in-Test Information 20 0x14
- control-U Active Station State 21 0x15
- control-V WhoAmI (Software versions) 22 0x16
- control-W Set Operational Configuration 23 0x17
- control-X Operational Configuration ID 24 0x18
- control-Y Initialize System 25 0x19
- control-Z Read Operational Configuration 26 0x1A
Hardware[edit]
Polhemus Patriot shipped with a 5V-rated power supply with positive on the center tip, negative on ring. It has a 2.5mm inner diameter and a 5.5mm outer diameter. It was manufactured by Globtek. It is compatible with the newer Polhemus Viper power supplies.
Patriot uses a 4-layer circuit board.
The plastic case of the SEU is a variant of the PolyCase JB-65.
Patriot High-speed[edit]
The main processor in the Polhemus Patriot High-speed is an Analog Devices ADSP-21161N digital signal processor (DSP). Final assembly of the chip was in Singapore.
Other electrical components on the board include:
- Cypress EZ-USB peripheral controller CY7C68013A
- Spansion S29AL008J flash memory, part number S29AL008J70TFI010
- 2x Cypress CY7C1041DV33 SRAM chips (Final assembly in Taiwan). Serve as external fast memory for the DSP.
- 2x MAX4664 analog switch chip
- 2x Fairchild 74LCX32 TSSOP-14
- Fairchild 74LCX541 TSSOP-20
- Maxim MAX3223 for the RS-232 serial connection
- Fairchild 74LCX138 TSSOP-16
- 2x Fairchild 74LCX574 TSSOP-20
- Analog Devices AD8602A amplifier
- 3x Analog Devices SSM2211 near the transmitter port
The Spansion flash memory only stores the firmware for the DSP. The cypress EZ-USB chip is an early model that downloads firmware from a host PC.
Transmitter side:
- MAX4582 analog multiplexer
- 1x SP721AG
- 2x National Semiconductor LM833 amplifier
- 2x AKM AK4384VT digital-to-analog converters
- 3X Vishay precision foil resistors (labeled B1046-VSRT and 2R0000 with 0.1 percent tolerance)
On the sensor side:
- Analog Devices AD623ARM amplifier (labeled J 0A), which has its voltage gain set to about 99, from a 1.02kOhm resistor labeled R137. This results in an approximate 40 decibel gain on this amp
- AKM AK5353VT 24-bit analog-to-digital converter powered by 5.00 volt power, giving a maximum input peak-to-peak of about 3 volts.
- 2x Burr-Brown INA163UA amplifier (one per sensor port)
- 2x MAX4582 analog multiplexer (one per sensor port)
- 2x Littelfuse SP721AG surge protection chips
IO:
- SP721AG near the serial port
References[edit]
- ↑ Sheerin, Peter (2004-02-03). "Polhemus Announces Patriot 6DOF Tracking System". https://www.gamedeveloper.com/game-platforms/polhemus-announces-patriot-6dof-tracking-system.
- ↑ http://www.linux-usb.org/usb.ids Accessed May 28, 2024