User manual LOGITECH 3D MOUSE & HEAD TRACKER

3D Mouse & Head Tracker Techical Reference Manuel 3D Mouse Head Tracker Logitech Inc., Fremont, CA 94555 ©1992 by Logitech, Inc. All Rights Reserved. Published 1992 Printed in the United States of America No part of this document may be copied or reproduced in any form or by any means without the prior written consent of Logitech, Inc. (Logitech). Logitech has made every effort to ensure the accuracy of this manual. However, Logitech makes no warranties with respect to this documentation band disclaims any implied warranties of merchantability and fitness for a particular purpose. The information in this document is subject to change without notice. Logitech assumes no responsibility for any errors that may appear in this document. Document: Released: 620402-00 Rev B November 1992 Trademarks IBM PC, XT, and AT are registered trademarks of International Business Machine Corp. Intel is a registered trademark and 80286, 80386, 286, 386, and 486 are trademarks of Intel Corp. Logitech is a trademark of Logitech, Inc. Microsoft, MS, and MS-DOS are registered trademarks of Microsoft Corp. StereoGraphics and Crystal Eyes are registered trademarks of StereoGraphics Corp. All other trademarks are the sole property of their respective manufacturers. U.S. Government Restricted Rights The software and associated documentation are provided with RESTRICTED RIGHTS. Use, duplication, or disclosure by the Government is subject to restrictions as set forth in subparagraphs (c) (1) and (I) of The Rights in Technical Data and Computer Software clause at DFARS 252.227-7013 or subparagraphs (c) (1) and (2) of the Commercial Computer Software-Restricted Rights at 48 CFR 52.227-19, as applicable. Contractor/manufacturer is Logitech Inc., 6505 Kaiser Drive, Fremont, CA 94555. FCC Warning Statement This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses, and can radiate radio frequency energy and, if not installed or used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try and correct the interference by one or more of the following measures: · Reorient or relocate the receiving antenna. · Increase the separation between the equipment and the receiver. · Connect the equipment into an outlet on a circuit different from that to which the receiver is connected. Consult the dealer or an experienced radio/TV technician for help. The user may find the following booklet prepared by the Federal Communications Commission helpful: How to Identify and Resolve Radio-TV Interference Problems. This booklet, #04-000-00345-4, is available from the U.S. Government Printing Office, Washington, D.C. 20402. To meet FCC requirements, shielded cables and power cords are required to connect the device to a personal computer or other Class B certified device. ii Information to User Changes or modifications to this equipment not expressly approved by the party responsible for compliance could void the user's authority to operate the equipment. FCC Compliance Statement This device complies with Part 15 of the FCC Rules. Operation is subject to the following two conditions: 1. This device may not cause harmful interference. 2. This device must accept any interference received, including interference that may cause undesired operation. Hardware Warranty by Fakespace, Inc. This product is warranted to be free from defects in material and workmanship for ninety days from the date of purchase. During this period, Fakespace will, at its sole option, replace or repair at no charge the product which, in its opinion, is defective. If the failed product has been modified without Fakespace's written consent or if the failure is the result of misuse, abuse, or misapplication, Fakespace has no obligation to repair or replace the failed product. Before returning a failed unit, the buyer must obtain a Return Authorization (RA) number by calling Fakespace Product Support at (650) 688-1940. Fakespace cannot be held responsible for any package returned without an RA number. The buyer is responsible for packing the product properly for return shipment, and for the charges to ship the product to Fakespace. Fakespace is responsible for charges to return the product to the buyer. EXCEPT AS EXPRESSLY PROVIDED ABOVE, THE HARDWARE AND ACCOMPANYING WRITTEN MATERIALS (INCLUDING THE USER'S MANUAL) ARE PROVIDED "AS IS" WITHOUT WARRANTY OF ANY KIND, INCLUDING THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE, EVEN IF LOGITECH HAS BEEN ADVISED OF THAT PURPOSE. IN NO EVENT WILL LOGITECH, INC. BE LIABLE FOR ANY DIRECT, INDIRECT, CONSEQUENTIAL, OR INCIDENTAL DAMAGES ARISING OUT OF THE USE OF OR INABILITY TO USE SUCH PRODUCT EVEN IF LOGITECH HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES. SOME STATES DO NOT ALLOW THE EXCLUSION OR LIMITATION OF LIABILITY FOR CONSEQUENTIAL OR INCIDENTAL DAMAGES, SO THE ABOVE LIMITATION MAY NOT APPLY. Software Public Domain Statement The following program files have been dedicated by Logitech to the public domain: TEST3D.EXE, SAMPLE.EXE, LOGIDRVR.C, LOGIDRVR.H, SIMPLE.C, and README.TXT. ACCORDINGLY, USE OF THIS SOFTWARE IS AT THE SOLE RISK OF THE USER, AND LOGITECH EXPRESSLY DISCLAIMS ANY LIABILITIES ARISING FROM THE USE OF THESE PROGRAM FILES, INCLUDING, WITHOUT OF LIMITATION WARRANTIES OF FITNESS FOR A PARTICULAR PURPOSE AND MERCHANTABILITY, AND NONINFRINGEMENT OF THIRD PARTY RIGHTS. iii iv Table of Contents Preface, ix 1 Introduction, 1 System Features, 1 Basic System Components, 2 Basic 3D Mouse Components, 2 Basic Head Tracker Components, 3 Additional Components and Features, 3 2 Installation and Setup, 5 Connecting the Components, 5 Arranging the Components, 7 Arranging the 3D Mouse Components, 7 Arranging the Head Tracker Components, 8 Custom Head Tracker Arrangements, 8 Running the TEST3D Program, 10 3 Component Description, 11 3D Mouse Transmitter, 11 3D Mouse Receiver, 12 Head Tracker Transmitter, 15 Head Tracker Receiver, 16 Control Unit, 16 Computer Cable, 18 Power Supply, 18 v Table of Contents Master/Slave Cable, 18 Audio Device (Optional), 18 4 Multiple Control Unit Components, 19 Connecting Multiple Control Units, 20 Connecting Components to Multiple Control Units, 22 5 System Operation, 23 3D Mode, 23 Coordinate System, 23 Right-Hand Rules, 24 Origin Points and Reference Axes, 26 Positional X, Y, Z Data, 27 Orientation Data, 28 Converting Euler's Angles to Quaternions, 30 Converting Degrees to Radians, 31 Active Area, 31 Resolution, 32 Fringe Area and Out-of-Range Area, 32 Tracking Speed, 35 Reporting Modes, 35 2D Mode, 36 Active Area, 36 Resolution, 36 Tracking Speed, 36 Reporting Mode, 36 vi Table of Contents 6 Application Programming Interface, 37 Control Unit Initialization, 37 3D Mode, 38 Mouse Data Report Format, 38 Data Format Restrictions, 40 3D Mode Commands, 40 2D Mode, 49 Reporting Data Formats, 49 2D Mode Commands, 52 7 Questions & Answers, 59 A 3D Mouse & Head Tracker Specifications, 61 B Creating a Custom Receiver, 69 Index, 71 vii viii Preface This manual describes the components and operation of the 3D Mouse and Head Tracker systems. The information in this manual is for technical reference. It is intended for OEMs (Original Equipment Manufacturers), VARs (Value Added Retailers), and software and hardware developers who integrate the 3D Mouse and Head Tracker technology into their products. Knowledge in the following areas would be beneficial, but is not required: · the C programming language, and the ability to adapt the code provided in this manual and associated software to your application-specific programming language · device driver development · RS-232 (serial) communication · 3D graphics programming This manual is organized as follows: Chapter 1, Introduction. This chapter introduces the 3D Mouse and Head Tracker system features and components. Chapter 2, Installation and Setup. This chapter describes how to install and setup the 3D Mouse and Head Tracker components. It also describes how to run TEST3D program. Chapter 3, Component Description. This chapter provides a detailed description of how each component works. Chapter 4, Using Multiple Control Units. This chapter describes when you need to use multiple control units, how to connect them, and which components to connect to them. Chapter 5, System Operation. This chapter describes how the 3D Mouse and Head Tracker systems communicate position and orientation data to the host computer. ix Table of Contents Chapter 6, Application Programming Interface. This chapter defines the 2D and 3D mode command set. Chapter 7, Questions & Answers. This chapter includes commonly asked questions about the 3D Mouse and Head Tracker systems and recommended answers. Appendix A, 3D Mouse & Head Tracker Specifications. This appendix lists the 3D Mouse and Head Tracker hardware specifications. Appendix B, Creating a Custom Receiver. This appendix provides information to help you create a custom 3D Mouse receiver. x 1 Introduction This chapter summarizes the 3D Mouse and Head Tracker system features. It also lists the basic system components, as well as additional components you can add for more sophisticated system configurations. System Features The award-winning, Logitech 3D Mouse and Head Tracker allow you to input three-dimensional, spatial information into a host computer, from IBM PC compatibles to high-end graphics workstations. These systems are designed for sophisticated software and hardware applications, including CAD/CAM, computer animation, computer modeling, robotic control, 3D graphics, and virtual reality workstations. The 3D Mouse and Head Tracker are easy to setup and use. The stationary transmitter emits ultrasonic signals that track the movement of the receiver. The receiver, which you move about threedimensionally within the active area in front of the transmitter, receives the ultrasonic signals and relays them back to the control unit. The control unit converts the signals into position and orientation data that can be processed by the host computer. Configuration of the 3D Mouse and Head Tracker components is very flexible. You can use just the 3D Mouse or the Head Tracker. You can use both the 3D Mouse and the Head Tracker receivers at the same time. Or, you can integrate the 3D Mouse and Head Tracker components into your own custom system. The configuration is up to your needs. The 3D Mouse operates in both 3D and 2D modes. The 3D mode reports three-dimensional and rotational positions. The 2D mode reports two dimensional positions just like an ordinary, conventional mouse. It is 100% compatible with Logitech and Microsoft pointing devices. The 3D Mouse and Head Tracker allow you to incorporate voice recognition and sound applications. The control unit provides an Audio-Out connector for you to connect an audio processing device and input sound through the receiver's top microphone. 1 Chapter 1 Basic System Components Before you install the 3D Mouse or Head Tracker, take a moment to familiarize yourself with the associated components. The product comes with either the 3D Mouse or Head Tracker components. For more detailed information about how these components work, see Chapter 3, "Component Description." Basic 3D Mouse Components The basic 3D Mouse system includes the components shown in Figure 1-1. 3D Mouse Transmitter Power Supply Computer Cable Control Unit POW OF OUT GE RAN NSM IT REC EIVE ER TRA 3D Mouse Receiver Figure 1-1. 3D Mouse Components 2 Introduction Basic Head Tracker Components The basic Head Tracker system includes a transmitter, receiver, control unit, power supply, and computer cable. Figure 1-2 shows the transmitter and receiver. Head Tracker Transmitter Head Tracker Receiver Figure 1-2. Head Tracker Transmitter and Receiver Additional Components and Features Multiple Control Units. You can connect up to four control units together for simultaneous head and hand tracking (tracking with up to four receivers and one transmitter). For more information about using multiple control units, see Chapter 4. Custom Devices. You can create a custom 3D Mouse receiver. Instructions and an electrical schematic appear in Appendix B. You can also create head tracking devices that incorporate the Head Tracker transmitter and receiver. These components include screw holes so you can mount them (see "Arranging the Head Tracker Components" in Chapter 2). Audio Processing Device Feature. You can add your own audio processing device to the 3D Mouse system for 3D applications with voice recognition and sound. Connect the audio processing device to the Audio Out connector on the control unit's rear panel. Input sound through the 3D Mouse or Head Tracker receiver's top microphone. 3 4 2 Installation and Setup This chapter describes how to setup and arrange the basic 3D Mouse and Head Tracker components. It also describes how to run the TEST3D program so you can ensure that the components work properly. Connecting the Components The transmitter, receiver, audio, computer, and power supply cables plug into the rear panel of the control unit. Figure 2-1 shows the connectors on the control unit's rear panel. The circled letters correspond with the components and the order you can connect them. ON POWER MASTER/SLAVE SERIAL PORT TRANSMITTER AUDIO OUT RECEIVER OFF E D B C A Figure 2-1. Control Unit Back Panel Connectors Follow these steps to connect the basic 3D Mouse or Head Tracker components: 1. Turn off your host computer. 2. Ensure that the control unit's On/Off switch is in the OFF position. We recommend that you do not turn on the control unit until you have finished connecting the components. 5 Chapter 2 3. Plug the receiver cable into the Receiver connector on the rear panel of the control unit (see A in Figure 2-1). The arrow on the cable should appear on top (see Figure 2-2). Figure 2-2. Positioning the Cable Arrow 4. Plug the transmitter cable into the Transmitter connector (see B in Figure 2-1). 5. (Optional) plug the audio cable into the Audio Out connector (see C in Figure 2-1). 6. Plug the rounded end of the computer cable into the Serial Port connector (see D in Figure 2-1). 7. Connect the computer cable's 9-pin plug into an available serial (COM) port in the back of your host computer. If your computer has a 25-pin serial port connector, attach the 9- to 25-pin adapter provided. Remember which serial port you use, because you will have to indicate it when you run the TEST3D program. 8. Plug the rounded end of the power supply cable into the Power Supply connector (see E in Figure 2-1). 9. Plug the power supply into an AC outlet or power strip. 10. Turn on your host computer. 11. Turn on the control unit. Flip the On/Off switch to the ON position. The red Power LED on the front panel of the control unit should light. 6 Installation and Setup Arranging the Components For optimum 3D Mouse and Head Tracker performance, arrange the components as described in the following sections. Arranging the 3D Mouse Components Typically, arrange the 3D Mouse components as shown in Figure 1-1 in Chapter 1. Ensure that there is sufficient cable length before connecting the components. Place the transmitter so that it faces the 3D Mouse receiver. Do not place any object between the transmitter and receiver. Make sure that the plane of the 3D Mouse transmitter is parallel to the plane of the host computer monitor. Work in a normal office environment. Do not work near equipment that emits loud noises or ultrasonic frequencies. Also, ensure that there are no reflective surfaces within 12 inches of the top and sides of the transmitter. If there is interference, relocate your system or create a sound-absorbing barrier. In 3D mode, ensure that there is enough space to move and rotate the receiver in a direct line of communication with the transmitter (see Figure 2-3) Figure 2-3. Holding 3D Mouse in Front of the Transmitter In 2D mode, ensure that there is enough space on your desk to move the receiver freely in a direct line of communication with the transmitter. 7 Chapter 2 Arranging the Head Tracker Components Arrange the Head Tracker components as discussed in the previous section "Arranging the 3D Mouse Components." However, when using the Head Tracker, the transmitter does not have to be parallel with the plane of the host computer's monitor. Custom Head Tracker Arrangements The Head Tracker transmitter and receiver have screw holes so you can mount them onto almost any custom device you design for your specific needs. This section shows two custom devices designed by two hardware developers that incorporate the Head Tracker components. The first device, which appears in Figure 2-4, shows a head-mounted image display designed by the Virtual Research company. The Head Tracker receiver is mounted onto the top of the Virtual ResearchTM helmet. The transmitter must be mounted overhead, within range, and in a direct line of communication with the receiver. The image on the display adjusts to movements of the user's head. Figure 2-4. Head Tracker Incorporated in Head-Mounted Display 8 Installation and Setup The second device, which appears in Figure 2-5, shows a user wearing virtual reality, Stereographics® Crystal Eyes® VR glasses and the 3D Mouse transmitter. These glasses, designed by the StereoGraphics® company, function as a receiver-three microphones are imbedded in the glasses frame. The Crystal Eyes® VR glasses allow the user to see a virtual, holographic image that appears to float in front of the host computer's monitor. As the user moves his/her head, the holographic image adjusts to the user's head movements. Figure 2-5. Custom Stereographics® Glasses with Microphones 9 Chapter 2 Running the TEST3D Program After you connect and arrange the 3D Mouse or Head Tracker components, we recommend that you run the TEST3D Program, provided on your program diskette. The TEST3D Program indicates whether the components work properly. To run the TEST3D Program, you must have an IBM PC or compatible computer with the following: · 386 or above · Coprocessor · VGA graphics adapter · 3 ½-inch disk drive · 2 MB (megabytes) of RAM · DOS 5.0 Also to run the TEST3D Program, you must first view the README.TXT information file, then follow the instructions in the "TEST3D User Documentation" section of the file. The README.TXT file also provides error messages that the TEST3D program generates and suggests corrective action. 10 3 Component Description This chapter provides a detailed reference for how the 3D Mouse and Head Tracker components work. 3D Mouse Transmitter The 3D Mouse transmitter includes three speakers that send 23 KHz ultrasonic signals to the receiver (see Figure 3-1; the dark pads cover the speakers). These ultrasonic signals track the receiver's position and orientation. The 3D Mouse transmitter communicates with either the 3D Mouse or Head Tracker receiver. The ultrasonic sound radiates from the center of each speaker in a 100 degree spherical cone. Where these three cones intersect is the active area of communication, see "Active Area" in Chapter 5. There should be no obstruction within the active area. The transmitter's cable connects to the control unit via the Transmitter connector. If you are using multiple control units, the transmitter connects to the "Master" control unit only (see "Multiple Control Unit Components" in Chapter 4). Figure 3-1. 3D Mouse Transmitter 11 Chapter 3 3D Mouse Receiver The 3D Mouse receiver has a triangle of microphones at the front end of the unit (see Figure 3-2; the three dark spots are the microphones). These microphones sample the ultrasonic signals from the transmitter at a rate of up to 50 times per second. The receiver relays these signals regarding its position and orientation to the control unit. Figure 3-2. 3D Mouse Microphones The 3D Mouse receiver samples the transmitter's ultrasonic signals within the active area of communication, see "Active Area" in Chapter 5. There should be no obstruction between the receiver and the transmitter within this active area. The top microphone supports audio input. The receiver's cable connects to the control unit via a Receiver connector. 12 Component Description The 3D Mouse receiver includes five, application-specific buttons: three top buttons and two side Suspend buttons (see Figure 3-3). The top buttons function like conventional Logitech mouse buttons-left, middle, and right. You can use these buttons in both 2D and 3D modes. Three top buttons (left, middle, right) Suspend button (right hand) Suspend button (right hand) Figure 3-3. 3D Mouse Receiver Buttons The 3D Mouse receiver is ergonomically designed to fit comfortably in the palm of either your right or left hand. The Suspend buttons function identically. The left Suspend button is for right-handed user. The right Suspend button is for left-handed users. In 2D mode when you move the 3D Mouse on your desktop, the Suspend buttons allow you to move the 3D Mouse without reporting its position to the host computer. This function is the same as picking up a conventional mouse from the desktop to reposition it without moving the screen cursor. In 3D mode, you can assign application-specific functions to the Suspend buttons. 13 Chapter 3 Hold the 3D Mouse receiver in a way that feels most comfortable to you. Figures 3-4 and 3-5 show two ways of holding the mouse in 3D mode. Figure 3-4. Holding the 3D Mouse Receiverin 3D Mode Hold the receiver up off the desktop and move and rotate it within the active area in front of the transmitter. Figure 3-5. 3D Mouse Receiver Buttons 14 Component Description In 2D mode, you can hold the 3D Mouse receiver in a way that feels most comfortable to you. One way of the holding the mouse is illustrated in Figure 3-6. Move the mouse around on the desktop within the active area of the transmitter. Figure 3-6. Holding the 3D Mouse Receiverin 2D Mode Head Tracker Transmitter The Head Tracker transmitter functions like the 3D Mouse transmitter discussed earlier in this chapter (see Figure 3-7; the three large circles are the speakers). Figure 3-7. Head Tracker Transmitter 15 Chapter 3 However, the Head Tracker transmitter is designed so you can mount it overhead. It includes three screw holes that allow you to mount it securely in a direct line of communication to the receiver. See "Arranging the Head Tracker Components" in Chapter 2. Head Tracker Receiver The Head Tracker receiver functions like the 3D Mouse receiver discussed earlier in this chapter (see Figure 3-8; the three large circles are the microphones). Figure 3-8. Head Tracker Receiver However, the Head Tracker receiver is designed so you can mount it to your custom head tracking devices. Therefore, it has no buttons. Three screw holes allow you to mount it securely onto custom devices (see "Arranging the Head Tracker Components" in Chapter 2). Control Unit The control unit is the heart of the 3D Mouse and Head Tracker systems. It contains a microprocessor, interface circuitry, and firmware that provides the functions of the system. Warning The control unit is fragile and cannot withstand being dropped nor rough treatment. The control unit decodes signals from the receiver and computes the receiver's position and orientation (rotation) about these coordinates (see Chapter 5, "System Operation"). In addition, the control unit 16 Component Description determines the status of all of the mouse buttons. It then reports this data to the host computer via a serial communication link. Figure 3-9 shows the control unit's front panel. This panel includes four LED's. The Power LED turns red when you turn on the control unit. The Transmit LED turns green each time the control unit sends a report to the host computer. During high-speed transmissions, such as stream mode, the Transmit LED turns on and off so quickly that it may appear dim. The Receive LED turns green when the control unit receives a command from the host computer. The Out of Range LED turns green when you move the receiver out of the active area of transmission or exceed the tracking speed (see Chapter 5, "System Operation"). TRANSMIT RECEIVE OUT OF RANGE POWER Figure 3-9. Control Unit Front Panel Figure 3-10 shows the control unit's rear panel. This panel provides connectors for all of the system components (see Chapter 2 for instructions for how to connect the components to the control unit). The rear panel also includes the On/Off switch ON POWER MASTER/SLAVE SERIAL PORT TRANSMITTER AUDIO OUT RECEIVER OFF Figure 3-10. Control Unit Rear Panel 17 Chapter 3 Computer Cable The 6-foot, EIA RS-232C computer cable connects the control unit to the host computer. Its 7-pin, mini-DIN end plugs into the control unit's rear panel. Its 9-pin, D-sub end plugs into the computer's serial port. (Pin assignments for the computer cable are listed in Appendix A.) If the 9pin plug doesn't fit your computer's serial port, use the 9- to 25-pin adapter. The computer cable provides data transmission rates of 1200 bps in 2D mode and 19,200 bps in 3D mode at full duplex, with no echo. Power Supply The external power supply delivers DC power to the system via the control unit. The power supply plugs into a 115-volt wall socket or a power strip. The barrel end of the power supply cable plugs into the Power connector in the control unit's rear panel. The system also supports an optional 220V power supply. Master/Slave Cable The Master/Slave cable, which plugs into the control unit's Master/Slave connector, connects up to four control units together. One of the cable's four plugs is labeled "Master"; the other plugs are labeled "Slave." Tighten each plug's screws to connect the Master/Slave cable securely to each control unit connector. Audio Device (Optional) You can connect your own audio processing device to the control unit's Audio Out connector. An audio processing device allows you to incorporate sound into 3D applications. (See Table A-1 in Appendix A for the Audio Out pin assignments and signal names.) Audio received by the top microphone of the receiver is amplified and routed through the LINE_OUT pin of the Audio Out connector. The EN_VOICE pin of the Audio Out connector is high when you press the Suspend button and low when you release it. The EN_VOICE pin provides support for "Push-to-Talk" applications. 18 4 Using Multiple Control Units You can include up to four control units in a 3D Mouse and/or Head Tracker setup. This arrangement is called "Master/Slave." There are several sophisticated situations when you need more than one control unit: · to allow one person to perform head and hand tracking at the same time on one monitor · to allow several people to perform head or hand tracking at the same time · to allow several people to work together on one project in their own virtual space This chapter describes the components that are necessary in a multiplecontrol unit setup, and how to connect the control units. Multiple Control Unit Components Figure 4-1 shows a block diagram of the components needed in a Master/Slave control unit arrangement. Here, one transmitter emits ultrasonic signals to each receiver and connects to the Master control unit. A receiver connects to each control unit and samples the transmitter's ultrasonic signals. You must connect a power supply to each control unit. Connect each control unit together in a daisy chain using a Master/Slave cable. Finally, connect each control unit to the host computer's serial ports. 19 Chapter 4 AC Master control unit Master/Slave cable Receiver Slave control unit Transmitter Slave control unit Host computer Slave control unit Figure 4-1. Multiple Control Unit Connecting Multiple Control Units Follow these steps to connect multiple control units: 1. Stack the control units, one on top of each other. You can include up to four control units. 2. Ensure that the On/Off switch on each control unit's rear panel is in the Off position. 3. Designate the Master control unit. It can be on the top or bottom of the stack. The other control units are called "Slave." 20 Using Multiple Control Units 4. Connect each control unit together using the Master/Slave cable shown in Figure 4-2. Plug the cable into the Master/Slave connector on each control unit's rear panel. Plug the "Master" plug into the control unit that you've designated the Master control unit. Plug the "Slave" connectors into the remaining control units. REC AUD ITTE R IO O UT EIVE R SER MAS POW ER TER /SLA VE IAL POR T TRA NSM REC AUD IO O UT EIVE R ON OFF MAS ER POW TER /SLA VE REC AUD ITTE R IO O UT EIVE R ON SER OFF MAS POW ER TER /SLA VE IAL POR T TRA NSM REC AUD ITTE R IO O UT EIVE R ON SER OFF MAS ER POW TER /SLA VE IAL POR T TRA NSM ON OFF Figure 3-10. Control Unit Rear Panel 21 Chapter 4 Connecting Components to Multiple Control Units Follow these steps to connect components to multiple control units: 1. Connect the transmitter to the "Master" control unit only. If you connect the transmitter to a "Slave control unit, the system will not work. Connect the transmitter's plug into the Transmitter connector on the "Master" control unit's rear panel. 2. Connect receivers to each control unit. Connect a receiver plug into each control unit's Receiver connector. 3. Connect a power supply cable to each control unit. Connect the plug end of the power supply cable into each control unit's Power connector. 4. Connect a computer cable to each control unit. Connect the rounded plug end of each computer cable into each control unit's Serial connector. 5. Turn off your host computer. 6. Connect each computer cable's 9-pin plug into a serial (COM) port in the back of the host computer. If your computer has a 25-pin serial port connector, attach the 9- to 25-pin adapters provided. Remember which serial ports you use, because you will have to indicate them when you run the TEST3D program (for IBM PCs only). 7. Turn on your host computer. 8. Turn on each control unit. Flip each On/Off switch to the ON position. The red Power LED on the front panels of each control unit should light. 22 5 System Operation The 3D Mouse and Head Tracker systems operate as follows: the transmitter emits ultrasonic signals. The control unit, via the receiver, detects these signals and derives receiver position and orientation data. The control unit reports this data and 3D Mouse button activity to the host computer. This chapter describes the following: · position and orientation data · the active area of operation of the 3D Mouse and Head Tracker systems in both 2D and 3D modes · the reporting modes the control unit provides in both 2D and 3D 3D Mode In 3D mode, you can move the 3D Mouse or Head Tracker receiver three-dimensionally along three axes-X, Y, Z-and rotate it about these axes. The control unit derives the receiver's position and orientation and reports this data to the host computer. Coordinate System In 3D mode, the 3D Mouse and Head Tracker systems use a rectangular, Cartesian coordinate system to report the relationship between the receiver and the transmitter-the receiver's position and orientation. 23 Chapter 5 Figure 5-1 shows the positive, three-dimensional direction of receiver movement-the X, Y, and Z axes. It also shows the positive rotation about these axes. Negative movement is in the direction opposite each arrow. 0 Degrees Yaw Rotation Y Origin X 0 Degrees Pitch Rotation Z 0 Degrees Roll Rotation Figure 5-1. Three-Dimensional Axes and Rotation Right-Hand Rules The 3D Mouse and Head Tracker systems use two right-hand rules to help you determine position and orientation. The first right-hand rule allows you to hold your thumb, index finger, and middle finger of the right hand at right angles to each other to indicate the positive direction of the X, Y, and Z axes (see Figure 5-2). 24 System Operation Y Z X Figure 5-3. Right-Hand Rule Showing the X, Y, Z Axis The second right-hand rule allows you to point your thumb in the positive direction of any axis and to curl your four fingers to represent positive rotation about that axis. In Figure 5-3, the thumb is pointed along the positive X axis, and the four fingers curl in the direction of positive rotation about that axis. Positive direction of rotation about the X axis Figure 5-3. Right-Hand Rule Showing Rotation About the X Axis 25 Chapter 5 Origin Points and Reference Axes The positional and orientation data generated by the control unit are based on the 3D origin points and reference axes. In Figure 5-4, the transmitter's origin point and reference axes are defined by the following: · XT is an imaginary reference axis that passes through the center of the transmitter's lower left speaker and through the center of the transmitter's lower right speaker. (Only the positive direction of this is shown in Figure 5-4.) · YT is an imaginary reference axis passing through the center of the transmitter's top speaker and is perpendicular to XT. · ZT is an imaginary reference axis perpendicular to both XT and YT. · The transmitter's origin is the point where XT, YT, and ZT intersect. Also in Figure 5-4, the receiver's origin point and reference axes are defined by the following: · XR is an imaginary reference axis passing through the center of the receiver's lower left microphone and through the center of the receiver's lower right microphone. (Only the positive direction of this axis is shown in Figure 5-4.) · YR is an imaginary reference axis passing through the center of the receiver's top microphone and is perpendicular to XR. · ZR is an imaginary reference axis perpendicular to both XR and YR. · The receiver's origin is the point where XR, YR, and ZR intersect. Note The transmitter's and receiver's origin points and reference axes described above also apply to the 3D Mouse transmitter and receiver. 26 System Operation YT Transmitter XT Origin YR ZT Receiver XR Origin ZR Figure 5-4. Transmitter and Receiver Origin Points and Reference Axes Positional X, Y, Z Data Positional data is the distance between the transmitter's and receiver's origin points. X Data. This is the distance the receiver's origin point is to the left or right (along the XT axis) of the transmitter's origin point (see Figure 5-4). Y Data. This is the distance the receiver's origin point is above or below (along the YT axis) the transmitter's origin point-minus a 12-inch offset (see Figure 5-4). When the receiver is sitting on the desktop level with the base of the transmitter, the Y data will be approximately a negative 12 inches. 27 Chapter 5 Z Data. This is the distance the receiver's origin point is away (along the ZT axis) from the transmitter's origin point-minus an 18-inch offset (see Figure 5-4). When the receiver is 6 inches away from the transmitter the Z axis, the Z data will be approximately a negative 12 inches. Orientation Data Orientation describes the rotation of the receiver with respect to the transmitter. The orientation is described using the aeronautical terms: Pitch, Yaw, and Roll. Pitch. Pitch orientation is positive or negative rotation about the receiver's X axis. Figure 5-5 shows positive Pitch rotation. Y X Z Figure 5-5. Positive Pitch Rotation 28 System Operation Yaw. Yaw orientation is positive or negative rotation about the receiver's Y axis. Figure 5-6 shows positive Yaw rotation. Y X Z Figure 5-6. Positive Yaw Rotation Roll. Roll orientation is positive or negative rotation about the receiver's Z axis. Figure 5-7 shows positive Roll rotation. Y X Z Figure 5-7. Positive Roll Rotation 29 Chapter 5 Orientation data is represented in Y-X-Z Euler's angles. For example, the orientation of 0 degrees Pitch, 0 degrees Yaw, and 0 degrees Roll is reported when both of the following conditions are met: · The receiver's reference axis ZR is parallel to the transmitter's reference axis ZT (see Figure 5-4). · The receiver's microphones are facing towards the transmitter's speakers. To position the receiver at a particular orientation (for example, Yaw = 30 degrees, Pitch = 40 degrees, and Roll = 50 degrees) from an initial starting orientation of zero degrees for Yaw, Pitch, and Roll, you must perform these steps in the order presented: 1. 2. 3. Yaw the receiver 30 degrees. Pitch the receiver 40 degrees. Roll the receiver 50 degrees. Converting Euler's Angles to Quaternions The Quaternions coordinate system is another way of representing orientation. This system uses four coordinates to specify orientation in a smoother, more natural way. (For more information about using Quaternions to specify rotation in space, see the Siggraph 1985 paper: "Animating Rotation with Quaternion Curves" by Ken Shoemake, San Francisco, July 22-26.) If you prefer to use Quaternions to define orientation instead of Euler's angles, the following formulas will help you convert from Euler's angles. w = cos (R/2) · cos (P/2) · cos (Y/2) + sin (R/2) · sin (P/2) · sin (Y/2) x = cos (R/2) · sin (P/2) · cos (Y/2) + sin (R/2) · cos (P/2) · sin (Y/2) y = cos (R/2) · cos (P/2) · sin (Y/2) + sin (R/2) · sin (P/2) · cos (Y/2) z = sin (R/2) · cos (P/2) · cos (Y/2) + cos (R/2) · sin (P/2) · sin (Y/2) 30 System Operation Converting Degrees to Radians Radians are a unit of angular measure for rotation. If you prefer to use radians instead of degrees, the following formulas will help you convert from degrees. To convert degrees to radians, use the following formulas: P = P · /180 Y = Y · /180 R = R · /180 Active Area From each transmitter speaker, ultrasonic sound disperses in a spherical, 100-degree cone. These three cones of sound overlap in a dispersion pattern shown in Figure 5-8. Where these cones overlap is the active area of communication. The active area extends 5 feet from each transmitter speaker. The receiver should be within this area. 100° Active area Figure 5-8. The Active Area 31 Chapter 5 Resolution In 3D mode within the active area, the resolution along the X, Y, and Z axes is 1/250 of an inch. The resolution in the Pitch, Yaw, and Roll rotations is 1/10 of a degree. Fringe Area and Out-of-Range Area The fringe area is a 1-foot band along the edge, within the active area (see the block diagram in Figure 5-9). Host computer Control unit Transmitter O -o ut f-r a e ng e ar a 100° Ou 4 t-o f-r an ge fe et 1 ar ea Ac e tiv ar ea Receiver Ac ti fo ot ve ar ea Fringe area Out-of-range area Figure 5-9. The Fringe and Out-of-Range Areas When you move the receiver into this fringe area, the control unit sets a FRINGE bit in the first byte of its data report to the host computer. (The control unit's data report tells the host computer the position and orientation of the receiver, see 3D Mode, Mouse Data Report Format" in Chapter 6.) The application can use the FRINGE bit to warn the user that the receiver is approaching the limits of the active area. 32 System Operation When the receiver is out of range, the control unit sets an OUT bit in the first byte of its data report to the host computer. This data report contains the last valid report when the receiver was in range. This last valid report allows the application to use the returned data report. If the receiver is out of range when the control unit returns the first data report, the control unit sets the OUT bit and the positional and orientation data contains all zeros. This allows the application to notify the user to move the receiver into range. Also, if the receiver's tracking speed exceeds 30 inches per second, the control unit sets the OUT bit. Note The FRINGE bit and the OUT bit are mutually exclusive; therefore, the control unit never sets both bits simultaneously. The FRINGE Bit The FRINGE bit is located at Bit 6 in the first byte of the 3D mode mouse data report (see Table 6-2 in Chapter 6). The OUT Bit The OUT bit is located at Bit 5 in the first byte of the 3D mode mouse data report (see Table 6-2 in Chapter 6). This bit signifies three out-ofrange conditions: · when you move the receiver out of the out-of-range area · when the receiver is not in a direct line of communication with the transmitter · when you move the receiver faster than the maximum tracking speed 33 Chapter 5 OUT Bit Set-First Report. The OUT bit in the first byte of the data report is as follows (if the receiver is not in range, and has never been in range since you powered on or initialized the control unit, when the report is requested): 1x1xxxxx* 00000000 byte 1 byte 2 through byte 16 *The letter "x" means "don't care," could be 0 or 1. This "all-zero" data report is repeated until you move the receiver in range, because the control unit always returns the last valid position and orientation in 3D mode. In this case, there has been no previously valid information. OUT Bit Example If your application converts absolute information into relative information, prompt the user to move the receiver into range before completing the control unit's initialization. This approach avoids a large relative change in position/orientation from the all-zero data report to the first valid data report. The following is a C pseudo-code example: // go get the data report get_report (report); // first report valid? if (report [0] & logitech_OUTBIT) { // first report invalid, request user to move the receiver printf ("Please move the Logitech receiver in range.\n"); // stick around until I get a valid data report do { // go get another report get_report (report); } while (report [0] & logitech_OUTBIT); //cheers to the user printf ("Logitech receiver detected.\n"); } // squirrel away the report for later processing save_report (report); 34 System Operation OUT Bit Set-Out of Range or Obscured. After the first data report, the unit always has a last-valid data report. Therefore when the receiver moves out of range or the ultrasonic path is obstructed, the position and orientation data reflects the last valid data report. For applications that convert absolute information to relative changes, the data report can usually be used as is. In effect, the sensor is not tracked until it is brought back into range. For applications using absolute information directly, old valid information is typically not acceptable to use. So, the OUT bit notifies the user, via the application, that the point is invalid. Note All the mouse buttons will operate regardless of the status of the OUT bit. In other words, the mouse does not need to be in range for button toggling. Tracking Speed In 3D mode, the receiver accurately tracks up to 30 inches per second (ips). If the speed exceeds 30 ips, the control unit sets the OUT bit. Reporting Modes In 3D mode, the control unit reports to the host computer in three modes: demand, incremental, and stream. Demand reporting mode is default. Demand Reporting Mode. In this mode, the control unit sends a single report only when requested by the host computer. Incremental Reporting Mode. In this mode, the control unit reports automatically each time the receiver changes position or orientation. Stream Reporting Mode. In this mode, the control unit reports at the maximum rate regardless of the receiver movement. 37 Chapter 5 2D Mode In 2D mode, you can move the 3D Mouse on a flat surface (the desktop or table). It behaves like a conventional 2- or 3-button mouse. The control unit reports button activity and two-dimensional movement to the host computer. Using the Suspend buttons or picking the mouse up from the desk suppresses mouse reports. These actions enable you to reposition the mouse without moving the screen object. Active Area In 2D mode, the active area is the same as in 3D mode; however, it is limited to a ½-inch space above the base of the transmitter on the Y axis. For example, if you raise the 3D Mouse over a ½ inch above the base of the transmitter, the receiver is out of range. Resolution In 2D mode, the resolution is 400 dpi within the active area. The resolution can be reduced at the driver level to support any resolution up to 400 dpi. Tracking Speed In 2D Mode, the 3D Mouse tracking speed is also 30 inches per second. Reporting Mode In 2D Mode, the control unit reports in Incremental report mode only. The maximum reporting rate is 44 reports per second. 36 6 Application Programming Interface This chapter describes how to initialize the control unit. It also describes the 2D and 3D mode command set. Examples of how to use the 3D Mode command set are included in the 3D Mouse driver source code provided on the program disk. Control Unit Initialization This section describes how to initialize or reset the control unit and the subsequent effects on the control unit. You can initialize the control unit in any one of three ways: a. b. Turn on the control unit. Send the *R (Software Reset) command to the control unit from the host computer (see the Software Reset command in the "3D Mode Commands" section later in this chapter). Perform an RTS line toggle on the RS-232 interface. The RTS toggle occurs when the RTS line is negative for at least 100 ms, and then becomes positive. (See restrictions below.) c. Procedures a. and b. cause the control unit to enter 3D Mode initialization. The three green LEDs on the control unit's front panel toggle on and off. 3D Mode initialization sets the serial port to 19,200 bps: 8 data bits, no parity, and 1 stop bit. No characters are sent back to the host computer. After 3D Mode initialization, the driver should wait at least 1 second and perform an * (Diagnostics) command to ensure that the control unit is functioning properly. For more information about the Diagnostics command, see the "3D Mode Commands" section later in this chapter. Procedure c. causes the control unit to enter 2D Mode initialization. 2D Mode initialization sets the serial port to 1200 bps: 7 data bits, no parity, and 1 stop bit. The end of the initialization sends the following twocharacter status message back to the host computer (see Table 6-1). 37 Chapter 6 Figure 6-1. 2D Mode End Status Message ASCII M,3 HEX 4D,33 Function 3 button device declaration This status message tells the host computer that the initialization routine has been completed and the control unit is in 2D Mode. Upon power on, reset, or RTS toggle, the 3D Mouse sends back one or two characters specifying the type of device-M3. The driver must determine what type of device is connected. This is performed by sending the *? (Send Standard Configuration) command. The device should respond within 100 ms. 3D Mode The sections that follow describe the 3D Mouse data report format, the data format restrictions, and the 3D Mode command set. Mouse Data Report Format The control unit reports 3D Mode activity to the host computer, such as position, orientation, and button activity via the mouse data report. The size of the mouse data report is 16 bytes (see Table 6-2). 38