RoboteQ AX2850 User Manual Download Page 1

AX2550
AX2850

Dual Channel
High Power 
Digital Motor
Controller 

User’s Manual

v1.9b, June 1, 2007

visit www.roboteq.com to download the latest revision of this manual

©Copyright 2003-2007 Roboteq, Inc.

Summary of Contents for AX2850

Page 1: ...AX2550 AX2850 Dual Channel High Power Digital Motor Controller User s Manual v1 9b June 1 2007 visit www roboteq com to download the latest revision of this manual Copyright 2003 2007 Roboteq Inc...

Page 2: ...2 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 3: ...odified Flashing Pattern Separate PID Gains for Ch1 and C2 changeable on the fly Miscellaneous additions and correction Added Amps Calibration option January 10 2007 1 9 Changed Amps Limit Algorithm M...

Page 4: ...4 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 5: ...onnecting the controller to your PC using Roborun 22 Obtaining the Controller s Software Revision Number 23 Exploring further 24 SECTION 3 AX2550 Motor Controller Overview 25 Product Description 25 Te...

Page 6: ...ration 52 Special Use of Accessory Digital Inputs 52 Using the Inputs to Activate the Buffered Output 52 Using the Inputs to turn Off On the Power MOSFET transistors 52 Self Test Mode 53 SECTION 6 Con...

Page 7: ...sing the PC Utility 83 SECTION 8 Closed Loop Position Mode 85 Mode Description 85 Selecting the Position Mode 85 Position Sensor Selection 86 Sensor Mounting 86 Feedback Potentiometer wiring 87 Feedba...

Page 8: ...ctor I O Pin Assignment R C Mode 110 R C Input Circuit Description 111 Supplied Cable Description 111 Powering the Radio from the controller 112 Connecting to a Separately Powered Radio 114 Operating...

Page 9: ...racter Echo 137 Command Acknowledgement 137 Command Error 137 Watchdog time out 137 RS 232 Watchdog 138 Controller Commands and Queries 138 Set Motor Command Value 139 Set Accessory Output 139 Query P...

Page 10: ...0 Encoder Hardware ID code 160 Switch Status 160 Speed or Distance 1 or 2 160 Counter Read Write Mailbox 161 Counter 1 and 2 161 Destination Register 1 and 2 161 Distance 1 and 2 162 Speed 1 and 2 162...

Page 11: ...84 Encoder Module Parameters Setting 185 Exercising the Motors 186 Viewing Encoder Data 186 Running the Motors 186 Logging Data to Disk 189 Connecting a Joystick 190 Using the Console 191 Viewing and...

Page 12: ...12 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 13: ...r and or power supply may occur if operated with a power supply alone See Power Regeneration Consid erations on page 37 of the Users Manual Always keep the controller connected to the Battery Use the...

Page 14: ...Important Safety Warnings 14 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 15: ...ith the addition of Optical Encoder inputs What you will need For a minimal installation gather the following components One AX2550 Controller and its provided cables 12V to 40V high capacity high cur...

Page 16: ...he back of the controller shown in the figure below are located all the wires that must be connected to the batteries and the motors Program Set Reset Connector to Receiver Controls and sensors Operat...

Page 17: ...wires instead since the added inductance on the motor side of the controller is not harmful The two red wires are connected to each other inside the controller The same is true for the black wires You...

Page 18: ...les a spark will be generated at the connection point This is a normal occurrence and should be expected Connecting to the 15 pin Connector The controller s I O are located on it s standard 15 pin D S...

Page 19: ...th the wire loop uncut assumes that the R C radio will be powered by the AX2550 controller Other wiring options are described in R C Operation on page 109 of the User s Manual Important Warning Do not...

Page 20: ...ctivate the motors to the desired speed and direc tion See R C Operation on page 109 of the User s Manual for a detailed description of the many features and options available in the R C mode Button O...

Page 21: ...o use the buttons to select and change the Motor Control mode from separate to mixed See Configuring the Controller using the Switches on page 171 of the User s Manual for a complete list of all the A...

Page 22: ...Press hold Prog Press and hold the Prog button for 10 seconds while resetting or powering on the controller After 10 seconds the controller will enter the program ming mode and flash alternatively the...

Page 23: ...vision num ber and present a series of buttons and tabs to enable its various possibilities The intuitive Graphical User Interface will let you view and change any of the controller s parameters The R...

Page 24: ...gain the cycle will repeat You will need to reset or power down and up the controller to exit and resume normal operation Now that you know your controller s software version number you will be able t...

Page 25: ...ss modem The controller s two channels can be operated independently or can be combined to set the forward reverse direction and steering of a vehicle by coordinating the motion on each side of the ve...

Page 26: ...d position measurement and enable advance robotic applications Technical features Fully Digital Microcontroller based Design Multiple operating modes Fully programmable using either built in switches...

Page 27: ...nel Internal Sensors Voltage sensor for monitoring the main 12 to 40V battery system operation Voltage monitoring of internal 12V Temperature sensors on the heat sink of each power output stage Sensor...

Page 28: ...re induced program fail ure Overvoltage and Undervoltage protection Regeneration current limiting Watchdog for automatic motor shutdown in case of command loss R C and RS232 modes Large bright run fai...

Page 29: ...em due to wir ing errors may have very serious consequences and will not be covered by the prod uct s warranty Power Connections The AX2550 has three Ground black two Vmot red power cables and a Power...

Page 30: ...of the motor drivers The microcomputer circuit is connected to a DC DC converter which takes power from either the Power Control wire or the VMot input The diode circuit is designed to automatically...

Page 31: ...igher voltage to keep the controller logic solidly On You may use a separate battery to keep the controller alive as the main Motor battery discharges The table below shows the state of the controller...

Page 32: ...o power the motors Connect the two thick red wires to the plus terminal of the bat tery The motor battery may be of 12 to 40 Volts 10 5V to 40V 0V Controller is On Power Stage is Off 10 5V to 40V 1V t...

Page 33: ...age 37 Important Warning Do not rely on cutting power to the controller for it to turn off if the Power Control is left floating If motors are spinning because the robot is pushed are pushed or becaus...

Page 34: ...ller output is typically determined empirically After connecting the motors apply a minimal amount of power using the Roborun PC util ity with the controller configured in Open Loop speed mode Verify...

Page 35: ...ncorpo rates a hardware setting inside the controller which ensures that both channels switch in a synchronized manner and respond to commands sent to channel 1 Converting the AX2550 to Single Channel...

Page 36: ...tion to the two power wires Fuse rating should be the sum of the expected cur rent on both channels Note that automotive fuses are generally slow will be of limited effectiveness in protecting the con...

Page 37: ...de of the controller If the controller must be located at a longer distance the effects of the wire inductance may be reduced by using one or more of the following techniques Twisting the power and gr...

Page 38: ...chargeable battery as supply to the Motor Power wires thick black and red wires If a transformer or power supply is used damage to the controller and or power supply may occur during regeneration See...

Page 39: ...due to the friction in the motor assembly motor gears load Any deceleration that would be quicker than natural friction means that braking energy will need to be taken out of the sys tem causing a rev...

Page 40: ...Connecting Power and Motors to the Controller 40 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 41: ...functions which can be combined to produce practically any desired mobile robot configuration Input Command Modes The controller will accept commands from one of the following sources R C radio Seria...

Page 42: ...load as when encountering an obstacle and change in slope This mode is adequate for most applications where the operator maintains a visual contact with the robot In the separate speed control mode c...

Page 43: ...Speed control operation is described in Closed Loop Speed Mode on page 97 Close Loop Position Control In this mode illustrated in Figure 18 the axle of a geared down motor is coupled to a potentiomete...

Page 44: ...uring normal operation current limiting is further enhanced by the techniques described in the following sections Temperature Based Current Limitation The AX2550 features active current limitation tha...

Page 45: ...ent The controller measures and limits the current that flows from the battery Current that flows through the motor is typically higher This counter intuitive phenomenon is due to the flyback current...

Page 46: ...PWM cycle lower than 100 resulting in a higher and potentially unsafe level through the motor and the controller Regeneration Current Limiting The AX2550 s current sensor is capable of measuring curr...

Page 47: ...alue in the MCU s configuration EEPROM Table 6 shows the corresponding acceleration for all Switch and RS232 settings Numerically speaking each acceleration value corresponds to a fixed percentage spe...

Page 48: ...et for each channel The factory default curve is a linear straight line meaning that after the joystick has moved passed the deadband point the motor s speed will change proportionally to the joy stic...

Page 49: ...n than the other In most situ ations this is not noticeable In others however it can be an inconvenience When operat ing in open loop speed control the AX2550 can be configured to correct the speed in...

Page 50: ...may be used to make the robot go straight in case of a natural ten dency to steer slightly to the left or to the right The Left Right adjustment parameter can be set from 5 25 to 5 25 in seven steps...

Page 51: ...Emergency Shut Down Using Controller Switches In case of emergency it is possibly to cause the controller to cut off the power to the motors by depressing the Program and Set buttons simultaneously a...

Page 52: ...gered by hits and bounces which may cause the controller to erroneously invert the commands Special Use of Accessory Digital Inputs The AX2550 includes two general purpose digital inputs identified as...

Page 53: ...wering up the controller After a few seconds the LEDs will display a sequence of two numerical digits and an optional letter separated by dashes as shown in the examples below After these digits are d...

Page 54: ...ility see Viewing and Logging Data in Analog and R C Modes on page 192 The string and data format is described in Analog and R C Modes Data Logging String For mat on page 166 Important Warning Disconn...

Page 55: ...ws a typical wir ing diagram of a mobile robot using the AX2550 controller The wires are used for connection to the batteries and motors and will typically carry large current loads Details on the con...

Page 56: ...2 Optional sensors Tachometers Closed loop Speed mode Potentiometers Servo mode Optical Encoder AX2850 only all closed loop modes 3 Motor Power supply wires 4 Power Control wire 5 Controller 6 R C Ra...

Page 57: ...erial com mand RS232 Activate Output C When Input is configured to drive Output C Turn FETs On Off When Input is configured as dead man switch input Inp E Digital Input Same as Input F Not available w...

Page 58: ...Output R C Data Out RS232 Data Logging Output RS232 Data Out RS232 Data Out Analog Data Out RS232 Data Logging Output 3 Input R C Ch 1 R C radio Channel 1 pulses RS232 Data In RS232 Data In from PC MC...

Page 59: ...na in 4 Accessory input E Dead man Switch Input Activate Output C Analog Input 4 in RevB Hardware Ana Input E Ana in 4 Accessory input E Dead man Switch Input Activate Output C Channel 2 speed or posi...

Page 60: ...arning Overvoltage spikes induced by switching inductive loads such as solenoids or relays will destroy the transistor unless a protection diode is used Connecting Switches or Devices to Input E Input...

Page 61: ...X2850 or on the AX2550 with the Encoder Module installed Remember that in RevB hardware InputE is shared with the Analog Input 4 If an analog sensor is connected the controller will return a Digital v...

Page 62: ...be inverted so that the robot may be driven upside down When neither Emergency Stop or Inverted modes are selected this input becomes a gen eral purpose input like the other two described above This i...

Page 63: ...ensors These inputs can be read at any time using the p query for Analog inputs 1 and 2 and the r query for Inputs 3 and 4 The following section show the various uses for these inputs Connecting Posit...

Page 64: ...arity if incorrect Note that while you are doing these tests the potentiometer must be loosely attached to the motor s axle so that it will not be forced and broken by the motor s uncontrolled rotatio...

Page 65: ...st installation Since in closed loop control the measured speed is the basis for the controller s power out put i e deliver more power if slower than desired speed less if higher an adjustment and cal...

Page 66: ...istics shown in the table below Thermistors are non linear devices Using the circuit described on Figure 35 the controller will read the following values represented in signed binary according to the...

Page 67: ...the A D reading into a voltage value is as follows Measured volts controller reading 128 0 255 5 Note The A D converter s reading is returned by the p command and is a signed 8 bit hexadecimal value...

Page 68: ...nternal Heatsink Temperature Sensors The AX2550 includes temperature sensors making contact with the each of the two Heat sink sides of the controller These sensors are used to automatically reduce th...

Page 69: ...235 230 224 217 208 199 188 177 165 153 140 128 116 104 93 83 74 65 58 51 45 40 35 31 27 24 21 19 17 15 13 12 11 9 8 int LoTemp HiTemp lobound hibound temp i i 38 while TempTable i AnaValue i 0 i if i...

Page 70: ...Connecting Sensors and Actuators to Input Outputs 70 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 71: ...the time interval between pulses or by the number of pulses within a given time period Because they are digital devices incremental encoders will measure distance and speed with perfect accuracy Since...

Page 72: ...the zero reference for all subsequent moves Recommended Encoder Types The module may be used with most incremental encoder module as long as they include the following features Two quadrature outputs...

Page 73: ...the first one The formula below gives the pulse frequency at a given RPM and encoder resolution in Pulses per Revolution Pulse Frequency in Hz RPM 60 PPR 4 Example a motor spinning at 10 000 RPM max w...

Page 74: ...the connectors and the new front bracket s opening around the RJ11 connector For added stability place the foam pad on top of the Encoder module as shown in Figure 44 so that it is held in place by t...

Page 75: ...with limit switches The figure and table below describe the connector and its pin assignment TABLE 14 Encoder Connector Pinout Pin Name Cable Color when using standard network cable 1 Encoder 2 Channe...

Page 76: ...urning in the forward direction the counter increments its value and a posi tive speed value is measured Using the PC utility it is possible to exercise the motors and view the encoder readings See En...

Page 77: ...cause a Switch Detection condition because the encoder s 0 level is below 0 5V which should be ignored In Figure 48 the encoder and switches are wired to the encoder module using a set of resistors d...

Page 78: ...he encoder goes through a 1k and 4 7k voltage divider thus creating a voltage that will never be below 0 8V at the encoder module s input When the switch is activated the module s input is pulled to 0...

Page 79: ...f stopping the motor when a limit is reached while allowing motion in the other direction away for that limit TABLE 15 Effects of Limit Switches 1 and 2 on Motor 1 SW1 SW2 Motor 1 Fwd Motor 1 Rev OFF...

Page 80: ...queries via the controller s serial port See RS232 Encoder Command Set on page 155 on page 82 Using the Encoder to Measure Speed The encoder module will automatically compute rotation speed for each e...

Page 81: ...sponds to the following measurable min actual RPM values RPM at Min Measurable Speed Value 1 58593 75 4 1 200 58 6 RPM The Roborun Utility automatically makes the above calculations when setting up th...

Page 82: ...where the motor shaft was at power up It is typically necessary to have the motors moved to a home position and reset the counters at that reference point RS232 Communication with the Encoder Module...

Page 83: ...e PC Utility Encoder Testing and Setting Using the PC Utility Extensive diagnostic calibration setting and testing support is provided in the Roborun PC utility Basic instructions on how to install an...

Page 84: ...Installing Connecting and Using the Encoder Mod 84 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 85: ...rive steering columns robotic arms life size models and other heavy loads The AX2550 incorporates a full featured Proportional Integral Differential PID control algorithm for quick and stable position...

Page 86: ...g Proper mounting of the sensor is critical for an effective and accurate position mode opera tion Figure 54 shows a typical motor gear box and sensor assembly The sensor is composed of two parts a bo...

Page 87: ...itical applications Optical encoders may also be used when operated as discussed in Using the Encoder to Measure Speed on page 80 Feedback Potentiometer wiring When using a potentiometer it must be wi...

Page 88: ...affixed at the bottom of the case Roborun will detect the new hardware revision and display Rev B on the screen Analog inputs 3 and 4 have different characteristics than inputs 1 and 2 and so require...

Page 89: ...controller is configured in Analog mode the analog input 1 is used for com mands while the analog input 4 is used for feedback Note that the analog inputs 3 and 4 are only available on the AX2550 wit...

Page 90: ...l never be reached The motor will turn continuously with no way of stopping it other than cutting the power or hitting the Emergency Stop button Determining the right polarity is best done experimenta...

Page 91: ...on either Encoder while a power level of 25 or higher is applied to the motor If such an error occurs the controller will halt permanently until its power is cycled or it is reset An Encoder error is...

Page 92: ...nly for the short time needed for the motor to move away from the limit switches Another method uses the AX2550 s Emergency Stop input to shut down the controller if any of the limit switches is tripp...

Page 93: ...justments to the Power Output based on the difference measured between the desired position set by the user and the actual position captured by the position sensor Figure 61 shows a representation of...

Page 94: ...value The differential component will also help dampen any overshoot and oscillation The Integral component of the algorithm performs a sum of the error over time In the posi tion mode this component...

Page 95: ...the Applied Power should be Applied Power Command Value Actual Position Proportional Gain Experiment first with the motor electrically or mechanically disconnected and verify that the controller is m...

Page 96: ...Closed Loop Position Mode 96 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 97: ...ional Integral Differential PID control algorithm for quick and stable speed control Selecting the Speed Mode The speed mode is selected by changing the Motor Control parameter in the controller to ei...

Page 98: ...ing from Control Loop Description on page 100 Optical Encoders require special handling See Installing Connecting and Using the Encoder Module on page 71 for a detailed discussion Tachometer or Encode...

Page 99: ...Stop but tons Determining the right polarity is best done experimentally using the Roborun utility see Using the Roborun Configuration Utility on page 177 and following these steps 1 Disconnect the c...

Page 100: ...speed value 5V or 0V on the analog input respectively when the motors are running at the max imum desired speed in either direction Since most tachometers will generate more than 2 5V a 10kOhm potent...

Page 101: ...or thus making the motor react more quickly to changes in commands and or motor load The Differential component of the algorithm computes the changes to the error from one 16 ms time period to the nex...

Page 102: ...ns and another screen for running and monitoring the motors First run the motor with the preset values Then experiment with different values until a satisfactory behavior is found In Speed Mode the In...

Page 103: ...LED Display The AX2550 uses a single 7 segment LED display to report a number of operating or fault conditions The type of reported information depends on the controller s operating context During no...

Page 104: ...ile the display indicates that the direction is forward In such a situa tion controller is set to apply the power in the forward direction to the output stage but the motor is stopped because the appl...

Page 105: ...received on either channel will enable the controller When enabled the controller will display the normal motor status described previously The no control message is displayed using the following sequ...

Page 106: ...nd up Permanent Faults are indicated with a rapidly flashing 8 Condition causing a permanent fault are Encoder Error Short Circuit detection Emergency Stop activation Emergency stop condition can be t...

Page 107: ...AX2550 Motor Controller User s Manual 107 Self Test Display Software version 1 9b FIGURE 67 Example of Software revision number display...

Page 108: ...Normal and Fault Condition LED Messages 108 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 109: ...le with all popular brands of R C transmitters A third R C channel can be used to control the On Off state of two outputs that may be con nected to electrical accessories valves lights weapons The R C...

Page 110: ...the Switches on page 171 Using the Roborun Configuration Utility on page 177 and Accessing Changing Configuration Parameter in Flash on page 143 Connector I O Pin Assignment R C Mode When used in R C...

Page 111: ...R C radio Channel 3 pulses Not available when encoder module present 10 Analog in Ana in 2 Channel 2 speed or position feedback input 11 Analog in Ana in 1 Channel 1 speed or position feedback input...

Page 112: ...e controller s connector may be used to power the R C radio The wire loop is used to bring the controller s power to the the radio as well as for powering the optocoupler stage Figure 73 below shows t...

Page 113: ...one wired in the R C cable deliv ered with the controller 8 9 15 Pin 1 Channel 1 Wire loop bringing power from controller to RC radio Channel 2 3 Channel 1 Command Pulses 4 Channel 2 Command Pulses 6...

Page 114: ...ntroller in R C mode In this operating mode the AX2550 will accept commands from a Radio Control receiver used for R C models remote controls The speed or position information is communicated to the A...

Page 115: ...esolution is superior to the one usually found in most low cost R C transmitters The AX2550 will therefore be able to take advantage of the better precision and better control available from a higher...

Page 116: ...ircuitry and will output a signal normally a safe condition value when radio communication is lost This signal will be inter preted by the AX2550 as a valid command and the controller will remain acti...

Page 117: ...disables the deadband Other values select a deadband according to the table below The deadband value applies equally to both joysticks The deadband is measured as a percentage of total normal joystick...

Page 118: ...e to give one side up to 10 more power than the other at the same settings This capability is described in detail in Left Right Tuning Adjustment on page 49 in the General Operation section of this ma...

Page 119: ...the Program button several times until the letter J is displayed If you miss it keep pressing the Program button for another cycle When the display flashes the letter J followed by the sign press the...

Page 120: ...In most cases this creates no undesired effect to the driving characteristics of the robot R C calibration only applies to the channel 1 and channel 2 inputs The accessory activation channel channel...

Page 121: ...seconds with the latest internal parameter val ues This information can be logged using the Roborun Utility see Viewing and Logging Data in Analog and R C Modes on page 192 It may also be stored in a...

Page 122: ...Version 1 9b June 1 2007 1 2 3 4 7 8 9 5 1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 6 RX Data RS232 Data Out GND R C Ch 1 R C Ch 2 R C GND R C 5V GND DB9 Female To PC DB15 Male To Controller FIGURE 82 Modifi...

Page 123: ...0 at 2 5V and 127 at 5V This value in turn becomes the com mand input used by the controller This command input is subject to deadband threshold and exponentiation adjustment Analog commands can be us...

Page 124: ...the PC for data logging 3 Data In Input unused 4 Input F Input See Special Use of Accessory Digital Inputs on page 52 5 Ground Out Power Output Controller ground 6 Unused Unused 7 Unused Unused 8 Inpu...

Page 125: ...ition in case the input is not connected The applied voltage must have suffi cient current low impedance so that it is not affected by these resistors Connecting a Potentiometer Figure 84 shows how to...

Page 126: ...e is too low or too high If the value is low an unnecessarily high and potentially damaging current will flow through the potentiometer The amount of current is computed as the voltage divided by the...

Page 127: ...be one of 8 values ranging from 0 to 7 which translate into a deadband of 0 to 16 Even though the deadband will cause some of the potentiometer movement around the center position to be ignored the co...

Page 128: ...ed through the Power Control input and the motor battery voltage drops below 5V the controller will be disabled until the analog commands are centered to the midpoint 2 5V on each input Data Logging i...

Page 129: ...can be safely ignored if it is not required in the application To read the output string while operating the controller with an analog command the cable must be modified to add an RS232 output wire an...

Page 130: ...Analog Control and Operation 130 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 131: ...less modems This connection can be used to both send commands and read various status information in real time from the controller The serial mode enables the design of autono mous robots or more soph...

Page 132: ...Dead man switch activation 5 and 13 Power Out Ground Controller ground 6 GND In Unused in RevB Hardware Ground Optocoupler GND Input Connect to pin 5 Unused in RevB Hardware 7 5V In Unused in RevB Ha...

Page 133: ...232 Cable The AX2550 is delivered with a 4 foot cable adapter which may be too short particularly if you wish to run and monitor the controller inside a moving robot RS232 extension cables are availab...

Page 134: ...connector Once connected you will need a Terminal Emulation program to display the data received from the controller on the PC s screen and to send characters typed on the keyboard to the controller...

Page 135: ...e hardware and can be ignored RS232 Communication with the Encoder Module The Encoder Module contains its own Microcontroller and firmware in Flash The Encoder s MCU communicates with the one on the m...

Page 136: ...ode and that it is now ready to accept commands Note that for improved safety the RS232 watchdog is automatically enabled when entering the RS232 in this way See RS 232 Watchdog on page 138 When reset...

Page 137: ...ller is not in the RS232 mode the controller is Off the controller may be defective Command Acknowledgement The AX2550 will acknowledge commands in one of two ways For commands that cause a reply such...

Page 138: ...and queries are composed of a series of 2 or 4 characters followed by the enter carriage return code The controller will send back echo every character it is receiving By checking that the returned ch...

Page 139: ...al digits from 00 to 7F Examples A00 channel 1 to 0 B7F channel 2 100 forward a3F channel 1 50 reverse Notes The hexadecimal number must always contain two digits For example a5 will not be recognized...

Page 140: ...tive No forward or reverse direction information is returned by this query This query is most useful for providing feedback to a microcontroller commanding the controller Query Amps from Battery to ea...

Page 141: ...res Description This query will cause the controller to return values based on the temperature measured by internal thermistors located at each heatsink side of the controller Because NTC ther mistors...

Page 142: ...input See Connect ing Sensors and Actuators to Input Outputs on page 55 for information on how to wire and use these signals The returned values are three sets of two digits with the values 00 to indi...

Page 143: ...eading and writing parameters is done using the fol lowing commands Read parameter Syntax mm Reply DD Where mm parameter number DD current parameter value Example 00 Read value parameter 0 01 Controll...

Page 144: ...Joystick Deadband or Analog Deadband Reset or FF 07 Exponentiation on channel 1 Instant 08 Exponentiation on channel 2 Instant 09 Reserved 0A Left Right Adjust Reset or FF 0B Encoder 1 Time Base when...

Page 145: ...ularly or on the fly All parameters in Flash except for the Amps calibration are reset to their default values every time new firmware is loaded into the controller Input Control Mode Address 00 Acces...

Page 146: ...Current flowing through the motors may be higher Bit Definition See pages 2 0 Motor Control Mode 0 A B separate speed open loop default 1 A B mixed speed open loop 2 A speed open loop B position 3 A B...

Page 147: ...ect of the controller s Digital Inputs and other settings Bit Definition See pages 7 0 0 very slow 1 slow 2 medium slow default 3 medium 4 fast 5 fastest See Programmable Acceleration on page 47 for c...

Page 148: ...1 and Channel 2 Address 08 Channel 1 09 Channel 2 Access Read Write Effective Instantly 5 4 Input E Unavailable when Encoder Module is present 00 No action default 01 Cut FET power when Input E is Lo...

Page 149: ...e Encoder Time base values that are loaded after the controller is reset or powered on Time Bases are used to determine rotation speed depending on the Encoder s resolution Time Bases can be changed a...

Page 150: ...n Access Read Write Effective After Reset or FF These parameters are the Gains values that are loaded after the controller is reset or pow ered on These Gains apply to both channels Gains can be chang...

Page 151: ...at are stored in Flash see above the Operating Parameters are stored in RAM and can be changed indefinitely After reset the Operating Parameters are loaded with the values stored in the Configuration...

Page 152: ...6ms iteration loop After reset these bits get initialized according to the configuration contained in Flash Values are in Hexadecimal Example 00000101 Hex 05 Read Change PID Values Address 82 P1 83 I1...

Page 153: ...The frequency is 15 625 Hz 255 Register Value The controller s default frequency provides the best efficiency and should be changed only if absolutely required and only if operating the controller in...

Page 154: ...t the Amps limit is at the current time This limit normally is the one that is preset by the user except when the controller is operating at high temperature in which case the allowable current drops...

Page 155: ...can be read as Absolute or Relative An Absolute counter read will return the full counter value after every read query In a Relative counter read the counter value is immediately cleared immediately...

Page 156: ...rly received and executed if an error occurred Examples Q2 Reset both counters Q5 Load value contained in buffer into counter 2 Q0 followed by Q1 Read counter 1 and copy its value into counter 2 Read...

Page 157: ...ll cause the controller to return either the speed or the distance computed by the Encoder module depending on the operating mode that is selected This command is similar to either of the two previous...

Page 158: ...stored in the Encoder s module MCU RAM While this command provides unrestricted access to up to 256 memory locations a small number of these locations should never be read or altered Parameter addres...

Page 159: ...Code 1 byte Full 85 Switches Status 1 byte Full 86 Speed or Distance 1 depending on operating mode 1 byte Full 87 Speed or Distance 2 depending on operating mode 1 byte Full 88 Counter Read Write Mail...

Page 160: ...Distance 1 or 2 Address 86 Channel 1 87 Channel 2 98 Destination Register 1 MSB bits 31 to 24 4 bytes Full 99 Destination Register 1 bits 23 to 16 9A Destination Register 1 bits 15 to 8 9B Destinatio...

Page 161: ...e which then copies the counter value into the mailbox The mailbox system can be used in the same way for reading and writing the des tination register In practice reading a counter is done by a singl...

Page 162: ...ned 8 bit value 127 to 127 that represents the motor speed relative to a maximum speed which in turn depends on the number of encoder counts and time base settings as described in Using the Encoder to...

Page 163: ...igher than 7 i e 8 to F to signify that the number is positive For negative numbers the Encoder module will insert an F ahead of any number string starting with a digit value lower than 8 i e 0 to 7 T...

Page 164: ...164 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 165: ...l 3 is activated the relay turns On and brings the RC radio signal 1 to the shared input The second relay contact brings a discharged capacitor onto the Power Control wire causing the controller to re...

Page 166: ...s composed of a start character delimiter followed by 12 or 13 two digit Hexa decimal numbers representing 12 or 13 internal parameter values and ending with a Car riage Return character The figure be...

Page 167: ...exadecimal is related to the binary system that is used at the very heart of micro computers Functions for converting from decimal to hexadecimal are readily available in high level languages such as...

Page 168: ...24 18 56 38 88 58 120 78 25 19 57 39 89 59 121 79 26 1A 58 3A 90 5A 122 7A 27 1B 59 3B 91 5B 123 7B 28 1C 60 3C 92 5C 124 7C 29 1D 61 3D 93 5D 125 7D 30 1E 62 3E 94 5E 126 7E 31 1F 63 3F 95 5F 127 7F...

Page 169: ...9 D1 15 241 F1 110 146 92 78 178 B2 46 210 D2 14 242 F2 109 147 93 77 179 B3 45 211 D3 13 243 F3 108 148 94 76 180 B4 44 212 D4 12 244 F4 107 149 95 75 181 B5 43 213 D5 11 245 F5 106 150 96 74 182 B6...

Page 170: ...170 AX2550 Motor Controller User s Manual Version 1 9b June 1 2007...

Page 171: ...for programming the AX2550 s settings Using the controller s built in switches and display This method is described in details in this chapter Using the PC based Configuration Utility See Using the R...

Page 172: ...the following steady pattern After 10 seconds the controller will enter the programming mode and flash a letter repre senting the first parameter in the list followed by its numerical value Important...

Page 173: ...ial Case of Joystick Calibration When the Joystick parameter is selected J and flashing pressing the Set key again will cause the controller to enter the Radio Control Joystick calibration sequence On...

Page 174: ...ontroller is reset or first powered up Programmable Parameters List The following table shows the AX2550 s controller parameters in the order they appear during programming as well as their valid valu...

Page 175: ...ex with watchdog 3 Analog mode page 109 page 131 page 123 2 C Motor Control mode 0 Separate A B speed control open loop default 1 Mixed A B speed control open loop For safety reasons the modes below c...

Page 176: ...h 2 no action default page 51 page 52 6 b Brake Coast Not implemented 7 d R C Joystick Dead band Analog Input Dead band 0 no deadband 1 8 2 16 default 3 24 4 32 5 40 6 46 7 54 page 117 page 127 8 E Ex...

Page 177: ...with a 9 pin female connector An Internet connection for downloading the latest version of the Roborun Utility or the Controller s Software 5 Megabytes of free disk space If there is no free serial po...

Page 178: ...n times two serial ports Look for one or two connectors resembling the illustration in Figure 97 If a serial port connector is already connected to something else it may be possible to unplug the curr...

Page 179: ...ion This frame will automatically be updated with an indication that a free communication port was found and opened by the utility If no free communication port is available on your computer it will b...

Page 180: ...ther by clicking on the desired tab 4 File and Program Management Commands This frame contains a variety of buttons needed to load and save the parameters from and to the controller or disk This frame...

Page 181: ...from Controller button After changing a parameter you must save it to the controller manually by pressing the Save to Controller button Control Settings The screen shown in Figure 100 is used to view...

Page 182: ...Operation on page 52 5 Effect of Digital Inputs This pull down menu allows the selection of the controller s response to changes on either of the two digital inputs See Special Use of Accessory Digita...

Page 183: ...ly changes in function of whether or not the Analog Input mode is selected If the Analog Input mode is selected on the main screen then this page is used to set the Analog Deadband value In the R C mo...

Page 184: ...tional Integral and Differential gains needed for the PID algorithm These PID gains are loaded after reset and apply to both channels Gains can be changed individually for each channels and on the fly...

Page 185: ...peed computation 3 Setting Divider for computing relative distance 4 Measure and display speed and relative distance 5 Measure and display counter values 6 Detect and display optional limit switch sta...

Page 186: ...e threshold level parameter and its operation is described in Voltage Levels Thresholds and Limit Switches on page 76 Exercising the Motors A set of buttons and sliders is provided to start stop commu...

Page 187: ...elow the slider The stop button will cause the slider to return to the middle stop position and a 0 value command to be sent to the controller The and buttons will cause the slider to move by 1 or 10...

Page 188: ...he Temp field displays the heat sink temperature for each channel The Bat Volt field displays the main battery s voltage voltage applied to the thick red wires The Ctrler Volt field displays the contr...

Page 189: ...n will capture all the parameters and save them in local RAM The data is not saved to disk until the Save to Disk button is pressed Data is being captured for as long as the program is in the Run mode...

Page 190: ...d It is strongly recommended that an USB rather than Analog joystick be used TABLE 36 Logged parameters order type and definition Parameter Header Data type range Measured Parameter Seconds Integer Ti...

Page 191: ...visualize in real time the robot s Amps consumption and other vital statistics during actual operating conditions Figure 105 shows the Console Screen and its various components 1 Terminal Screen This...

Page 192: ...s data This feature makes it possible to view and log the controller s internal parameters while it is used in the actual application The data may be captured using a PC connected to the controller vi...

Page 193: ...named Roboserver This program is automatically installed in the Start menu when install ing the Roborun utility This program s function it to wait for and accept TCP IP connection requests from the o...

Page 194: ...k easy and error proof 1 Connect the controller to the PC via the provided RS232 cable 2 Apply a 12V to 40V power supply to the controller s Ground and Power Control input thin black and yellow wires...

Page 195: ...updated using the Roborun Utility in the same manner as for updating the controller s soft ware see Updating the Controller s Software on page 194 Then select the new soft ware file to download The fi...

Page 196: ...desired param eter value 2 Launch Objectmaker from the Start menu 3 Select the latest official controller firmware issued by Roboteq 4 Select the profile file that was created and saved earlier 5 Sel...

Page 197: ...tions This section details the mechanical characteristics of the AX2550 controller Mechanical Dimensions The AX2550 is built into a extruded aluminum case which also serves as a heat sink for its elec...

Page 198: ...on 1 9b June 1 2007 Mounting Considerations Program Set Reset 5 50 140 mm 4 00 102 mm 1 60 40 mm FIGURE 110 AX2550 front view and dimensions 0 25 6 3 mm 7 00 177 8 mm 5 50 140 mm 4 00 101 6 mm 3 00 76...

Page 199: ...to a Chassis The AX2550 can be attached to a metal chassis to improve heat dissipation You may mount the controller so that its bottom area is in contact with large metallic parts of the robot s body...

Page 200: ...1 9b June 1 2007 Weight Controller weight is 3 3 lbs 1500g Power Control or Backup Controller Battery AWG22 0 07 1 8mm Yellow 17 43mm Controller Battery AWG22 0 07 1 8mm Black 17 43mm TABLE 37 AX2550...

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