AgileX HUNTER User manual

AgileX Product HUNTER User Manual
AgileX Robotics Team
Version1.2 Release
20196

AgileX robotics (Dongguan) Co., Ltd.
1
Revision History
Version
Content of Changes
Person in
Charge
Date
v1.2.6
1. [New addition] Added the Revision History
2. [New addition] Added motor feedback information
3. [Modification] Modified supported maximum current on
top
Xie Zhiqiang
2019/9/2
v1.2.7
1. [Modification] Modified known errors
Xie Zhiqiang
2019/9/25

AgileX robotics (Dongguan) Co., Ltd.
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CONTENTS
1. Introduction.......................................................................................................................................................... 3
1.1 Component list ........................................................................................................................................... 3
1.2 Tech specifications ..................................................................................................................................... 3
2. The Basics............................................................................................................................................................. 5
2.1 Status indication......................................................................................................................................... 6
2.2 Instructions on electrical interfaces ......................................................................................................... 6
2.2.1 Top electrical interface ................................................................................................................... 6
2.2.2 Rear electrical interface ................................................................................................................. 7
2.3 DJI Remote control instructions............................................................................................................... 8
2.3.1 DJI remote control instructions......................................................................错误!未定义书签。
2.3.3 FS_i6_S remote control instructions ............................................................................................. 8
2.3 Instructions on control demands and movements .................................................................................. 9
3. Getting Started................................................................................................................................................... 10
3.1 Use and operation .................................................................................................................................... 10
3.2 Charging................................................................................................................................................... 10
3.3 Communication using CAN .....................................................................................................................11
3.3.1 CAN message protocol...................................................................................................................11
3.3.2 CAN cable connection .................................................................................................................. 18
3.3.3 Implementation of CAN command control ................................................................................ 19
3.4 Firmware upgrades.................................................................................................................................. 19
4. Precautions ......................................................................................................................................................... 21
4.1 Battery ...................................................................................................................................................... 21
4.2 Operational environment........................................................................................................................ 21
4.3 Electrical/extension cords........................................................................................................................ 21
4.4 Mechanical load ....................................................................................................................................... 22
4.5 Other notes ............................................................................................................................................... 22
5. Q&A.................................................................................................................................................................... 23
6. Product Dimensions........................................................................................................................................... 24
6.1 Illustration diagram of product external dimensions........................................................................... 24
6.2 Illustration diagram of top extended support dimensions ................................................................... 25

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1. Introduction
HUNTER is designed as a programmable UGV upon Ackermann model, of which the chassis is based
on Ackermann steering. Therefore, it has similar characteristics to cars but has more significant
advantages on Portland cement and asphalt roads over them. Compared to the four-wheel differential
chassis, HUNTER chassis has a higher load carrying capacity and can reach higher movement speed
with less wear of structure and tires for long-term operation. Although HUNTER is not designed as
suitable for all kinds of terrains, it is equipped with a rocker arm suspension which can pass common
obstacles such as speed bumps, etc. Additional components such as stereo camera, laser radar, GPS,
IMU and robotic manipulator can be optionally installed on HUNTER for advanced navigation and
computer vision applications. HUNTER is frequently used for autonomous driving education and
research, indoor and outdoor security patrolling, environment sensing, general logistics and
transportation, to name here only.
1.1 Component list
Name
Quantity
Robot body
X 1
Key lock
X 1
Battery charger (AC 220V)
X 1
Aviation plug (male, 4-pin)
X 2
DJI remote control transmitter(optional)
X 1
1.2 Tech specifications
Parameter Types
Items
Values
Mechanical
specifications
L × W × H (mm)
980 X 718 X 330
Wheelbase (mm)
650
Front/rear wheel base (mm)
578
Weight of vehicle body (kg)
45~50
Battery type
Lithium battery 24V 20aH
Power drive motor
DC brushless 2 X 200W
Steering drive motor
DC brushless 200W
Reduction gearbox
1:30
Drive type
Rear wheel drive
Steering
Front wheel Ackermann
Maximum steering angle
30°
Steering accuracy
0.5°
Motion
No-load highest speed (m/s)
1.5
Minimum turning radius (mm)
1700
Maximum climbing capacity
20°
Minimum ground clearance (mm)
105
Control
Control mode
Remote control
Control command mode
RC transmitter
2.4G/extreme distance 1km
Communication interface
CAN / RS232

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DJI/FS RC transmitter is provided (optional) in the factory setting of HUNTER, which allows users
to control the chassis of robot to move and turn; CAN and RS232 interfaces on HUNTER can be used
for user’s customization.

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2. The Basics
This section provides a brief introduction to the HUNTER mobile robot platform, as shown in Figure
2.1 and Figure 2.2.
Figure 2.1 Front View
Figure 2.2 Rear View
Designed as a complete intelligent module, HUNTER combines inflatable rubber wheels with
independent suspension as its power module, which, along with powerful DC brushless servo motor,
enables the chassis of HUNTER robot to flexibly move on different ground surfaces with high passing
ability and ground adaptability.
Bridge-type Suspension
Front Wheel Steering
Standard Support
Top Electrical Panel
Top Compartment Panel
Emergency Stop Switch
Rear Panel
Top Compartment Panel
Top Electrical Panel
Standard Profile Support
Rear Wheel Drive

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An emergency stop switch is mounted at the rear end of vehicle body, which can shut down power of
the robot immediately when the robot behaves abnormally.
Water-proof connectors for DC power and communication interfaces are provided both on top and at
the rear of the robot, which not only allow flexible connection between the robot and external
components but also ensures necessary protection to the internal of the robot even under severe
operating conditions.
2.1 Status indication
Users can identify the status of vehicle body through the voltmeter, the beeper and lights mounted on
HUNTER. For details, please refer to Table 2.1.
Table 2.1 Descriptions of Vehicle Status
Status
Description
Voltage
The current battery voltage can be read from the voltmeter on the
rear electrical interface and with an accuracy of 1V.
Replace battery
When the battery voltage is lower than 22V, the vehicle body will
give a beep-beep-beep sound as a warning. When the battery
voltage is detected as lower than 21.5V, HUNTER will actively cut
off the power supply to external extensions and drive to prevent
the battery from being damaged. In this case, the chassis will not
enable movement control and accept external command control.
Robot powered on
Front and rear lights are switched on.
2.2 Instructions on electrical interfaces
2.2.1 Top electrical interface
HUNTER provides two 4-pin aviation connectors and one DB9 (RS232) connector. (The current
version can be used for upgrade of firmware but do not support for command).
The position of the top aviation connector is shown in Figure 2.3.
Figure 2.3 Schematic Diagram of HUNTER Electrical Interface on Top
External Extension
Interface
Beeper

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HUNTER has each aviation extension interface respectively on top and at rear end which is
configured with a set of power supply and a set of CAN communication interface. These interfaces
can be used to supply power to extended devices and establish communication. The specific
definitions of pins are shown in Figure 2.4.
It should be noted that, the extended power supply here is internally controlled, which means the
power supply will be actively cut off once the battery voltage drops below the pre-specified threshold
voltage. Therefore, users need to notice that HUNTER platform will send a low voltage alarm before
the threshold voltage is reached and also pay attention to battery recharging during use.
Pin No.
Pin Type
Function and
Definition
Remarks
1
Power
VCC
Power positive, voltage range 23 -
29.2V, MAX. current 10A
2
GND
Power negative
3
CAN
CAN_H
CAN bus high
4
CAN_L
CAN bus low
Figure 2.4 Definitions for Pins of Top Aviation Extension Interface
2.2.2 Rear electrical interface
The extension interface at rear end is shown in Figure 2.4, where Q1 is the key switch as the main
electrical switch; Q2 is the recharging interface; Q3 is the power supply switch of drive system; Q4
is DB9 serial port (The current version can be used for upgrade of firmware but do not support for
command); Q5 is the extension interface for CAN and 24V power supply; Q6 is the display interaction
of battery voltage.
Figure 2.4 Rear View
Specific definitions for pins of Q4 are shown in Figure 2.5.
Emergency Stop Switch
Rear View
Rear Panel

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Pin No.
Definition
2
RS232-RX
3
RS232-TX
5
GND
Figure 2.5 Illustration Diagram of Q4 Pins
The rear panel provides the same CAN communication interface and 24V power interface with
the top one (two of them are internally inter-connected). The pin definitions are given in Figure
2.6.
Pin No.
Pin Type
Function and
Definition
Remarks
1
Power
VCC
Power positive, voltage range 23 -
29.2V, maximum current 5A
2
GND
Power negative
3
CAN
CAN_H
CAN bus high
4
CAN_L
CAN bus low
Figure 2.6 Description of Rear Aviation Interface Pins
2.3 DJI Remote control instructions
FS_i6_S remote control instructions
FS RC transmitter is an optional accessory of HUNTER for manually controlling the robot. The
transmitter comes with a left-hand-throttle configuration. In addition to the two sticks S1 and S2 used
for sending linear and angular velocity commands, two switches are enabled by default: SWB for
control mode selection (top position for command control mode and the middle position for remote
control mode), SWC for lighting control. The two POWER buttons need to be pressed and held
together to turn on or turn off the transmitter.

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Figure 2.9 Schematic Diagram of Buttons on FS RC transmitter
2.3 Instructions on control demands and movements
A reference coordinate system can be defined and fixed on the vehicle body as shown in Figure 2.8
in accordance with ISO 8855.
Figure 2.8 Schematic Diagram of Reference Coordinate System for Vehicle Body
As shown in Figure 2.8, the vehicle body of HUNTER is in parallel with X axis of the established
reference coordinate system. Following this convention, a positive linear velocity corresponds to the
forward movement of the vehicle along positive x-axis direction and a positive angular velocity
corresponds to positive right-hand rotation about the z-axis. In the manual control mode with a RC
transmitter, pushing the C1 stick (DJI model) or the S1 stick (FS model) forward will generate a
positive linear velocity command and pushing C2 (DJI model) and S2 (FS model) to the left will
generate a positive angular velocity command.

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3. Getting Started
This section introduces the basic operation and development of the HUNTER platform using the
CAN bus interface.
3.1 Use and operation
The basic operating procedure of startup is shown as follows:
•Check
◼Check the condition of vehicle body. Check whether there are significant anomalies; if so,
please contact the after-sale service personnel for support;
◼Check the state of emergency-stop switches. Make sure both emergency stop buttons are
released;
◼Take off the cover of rear panel and you will see it;
◼For first-time use, check whether Q3 (drive power supply switch) on the rear panel has been
pressed down; if so, please release it, and then the drive will be powered off;
•Startup
◼Rotate the key switch (Q1 on the electrical panel), and normally, the voltmeter will display
correct battery voltage and front and rear lights will be both switched on;
◼Check the battery voltage. If there is no continuous "beep-beep-beep..." sound from beeper,
it means the battery voltage is correct; if the battery power level is low, please charge the
battery;
◼Press Q3 (drive power switch button);
•Shutdown
◼Rotate the key switch to cut off the power supply;
•Emergency stop
◼Press down emergency push buttons both on the left and the right of HUNTER vehicle body;
Basic operating procedure of remote control
After the chassis of HUNTER mobile robot is started correctly, turn on the RC transmitter and select
the remote control mode. Then, HUNTER platform movement can be controlled by the RC transmitter.
3.2 Charging
HUNTER is equipped with a 10A charger by default to meet customers' recharging demand.
The detailed operating procedure of charging is shown as follows:
•Make sure the electricity of HUNTER chassis is powered off. Before charging, please make sure
Q1 (key switch) in the rear control console is turned off;

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•Insert the charger plug into Q2 charging interface on the rear control panel;
•Connect the charger to power supply and turn on the switch in the charger. Then, the robot enters
the charging state.
Note: For now, the battery needs about 3 to 5 hours to be fully recharged from 22V, and the voltage
of fully-recharged battery is about 29.2V; the recharging duration is calculated as 30aH ÷ 10A = 3h
3.3 Communication using CAN
HUNTER provides CAN and RS232 (not open to current version) interfaces for user customization.
Users can select one of these interfaces to conduct command control over the vehicle body.
3.3.1 CAN message protocol
HUNTER adopts CAN2.0B communication standard which has a communication baud rate of 500K
and Motorola message format. Via external CAN bus interface, the moving linear speed and the
rotational angular speed of chassis can be controlled; HUNTER will feedback on the current
movement status information and its chassis status information in real time.
The protocol includes system status feedback frame, movement control feedback frame and control
frame, the contents of which are shown as follows:
The system status feedback command includes the feedback information about current status of
vehicle body, control mode status, battery voltage and system failure. The description is given in
Table 3.1.
Table 3.1 Feedback Frame of HUNTER Chassis System Status
Command
Name
System Status Feedback Command
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout (ms)
Steer-by-wire
chassis
Decision-making control
unit
0x151
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
Current status of vehicle
body
unsigned
int8
0x00 System in normal condition
0x01 Emergency stop mode (not enabled)
0x01 System exception
byte [1]
Mode control
signed int8
0x00 Remote control mode
0x01 Command control mode
byte [2]
Battery voltage higher 8
bits
unsigned
int16
Actual voltage X 10 (with an accuracy of 0.1V)
byte [3]
Battery voltage lower 8
bits
byte [4]
Failure information
higher 8 bits
unsigned
int16
See notes for details 【**】
byte [5]
Failure information
lower 8 bits
byte [6]
Count parity bit (count)
unsigned
int8
0 - 255 counting loops, which will be added
once every command sent
byte [7]
Parity bit (checksum)
unsigned
int8
Parity bit

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Description of Failure Information
Byte
Bit
Meaning
byte [4]
bit [0]
Check error of CAN communication control command (0: No
failure 1: Failure)
bit [1]
Abnormal condition of front wheel steering encoder (0: No
failure 1: Failure)
bit [2]
RC transmitter disconnection protection (0: No failure 1:
Failure)[1]
bit [3]
Reserved, default 0
bit [4]
Reserved, default 0
bit [5]
Reserved, default 0
bit [6]
Reserved, default 0
bit [7]
Reserved, default 0
byte [5]
bit [0]
Battery under-voltage failure (0: No failure 1: Failure)
bit [1]
Battery over-voltage failure (0: No failure 1: Failure)
bit [2]
No.1 motor communication failure (0: No failure 1: Failure)
bit [3]
No.2 motor communication failure (0: No failure 1: Failure)
bit [4]
No.3 motor communication failure (0: No failure 1: Failure)
bit [5]
No.4 motor communication failure (0: No failure 1: Failure)
bit [6]
Motor drive over-temperature failure (0: No failure 1: Failure)
bit [7]
Motor over-current failure (0: No failure 1: Failure)
Note [1]: The RC transmitter disconnection protection only supports FS RC transmitter; DJI
RC transmitter is not supported and only available in manual mode.

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The command of movement control feedback frame includes the feedback of current linear speed and
angular speed of moving vehicle body. For the detailed content of protocol, please refer to Table 3.2.
Table 3.2 Movement Control Feedback Frame
Command Name
Movement Control Feedback Command
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Steer-by-wire
chassis
Decision-making
control unit
0x131
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
Moving speed
higher 8 bits
signed int16
Actual speed X 1000 (with an accuracy of
0.001m/s)
byte [1]
Moving speed
lower 8 bits
byte [2]
Internal steering
angle higher 8 bits
signed int16
Actual speed X 1000 (with an accuracy of
0.001rad)
byte [3]
Internal steering
angle higher 8 bits
byte [4]
Reserved
-
0x00
byte [5]
Reserved
-
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
The control frame includes mode control, failure clearing command, control openness of linear speed,
control openness of internal steering angle and checksum. For its detailed content of protocol, please
refer to Table 3.3.
Table 3.3 Control Frame of Movement Control Command
Command Name
Control Command
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Decision-making
control unit
Chassis node
0x130
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
Control mode
unsigned int8
0x00 Remote control mode
0x01 Command control mode [1]
0x01 Command
control mode [1]
byte [1]
Failure clearing
command
unsigned int8
See Note 2 for details*
byte [2]
Linear speed
signed int8
Maximum speed 1.50m/s, value range (-

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percentage
100, 100)
byte [3]
Internal steering
angle percentage
signed int8
Maximum internal steering angle (-43°,
43°), value range (-100, 100)
byte [4]
Reserved
-
0x00
byte [5]
Reserved
-
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
Note 1 - Control mode instructions
In case the RC transmitter is powered off, the control mode of HUNTER is defaulted to
command control mode, which means the chassis can be directly controlled via command.
However, even though the chassis is in command control mode, the control mode in the
command needs to be set to 0x01 for successfully executing the speed command. Once the RC
transmitter is switched on again, it has the highest authority level to shield the command control
and switch over the control mode.
Note 2 - Information about failure clearing command:
•0x00 No failure clearing command
•0x01 Clear battery under-voltage failure
•0x02 Clear battery over-voltage failure
•0x03 Clear No. 1 motor communication failure
•0x04 Clear No. 2 motor communication failure
•0x05 Clear No. 3 motor communication failure
•0x06 Clear No. 4 motor communication failure
•0x07 Clear motor drive over-temperature failure
•0x08 Clear motor over-current failure
Command Name
Function Setting Command
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Decision-making
control unit
Chassis node
0x210
None
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
Set the current
position to zero
unsigned int8
0x00 Invalid
0xAA Set the current position to zero
byte [1]
Reserved
-
0x00

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byte [2]
Reserved
-
0x00
byte [3]
Reserved
-
0x00
byte [4]
Reserved
-
0x00
byte [5]
Reserved
-
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit (checksum)
unsigned int8
Parity bit
Command name
Function Setting Feedback Command
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Decision-making
control unit
Chassis node
0x211
None
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
Feedback of zero
status setting
unsigned int8
0x00 Invalid
0xAA Set the current position to zero
successfully
byte [1]
Reserved
-
0x00
byte [2]
Reserved
-
0x00
byte [3]
Reserved
-
0x00
byte [4]
Reserved
-
0x00
byte [5]
Reserved
-
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
Note 3 - Example data: The following data is only used for testing
1. The vehicle moves forward at 0.15m/s
byte [0]
byte [1]
byte [2]
byte [3]
byte [4]
byte [5]
byte [6]
byte [7]
0x01
0x00
0x0a
0x00
0x00
0x00
0x00
0x44
2. The front wheels of vehicle steer by 4.3°
byte [0]
byte [1]
byte [2]
byte [3]
byte [4]
byte [5]
byte [6]
byte [7]
0x01
0x00
0x00
0x0a
0x00
0x00
0x00
0x44
3. When the vehicle stays still, switch the control mode to command mode (test without RC
transmitterswitchedon)
byte [0]
byte [1]
byte [2]
byte [3]
byte [4]
byte [5]
byte [6]
byte [7]

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0x01
0x00
0x00
0x00
0x00
0x00
0x00
0x3a
The chassis status information will be fed back, and what’s more,the information about motor current,
encoder and temperature are also included. The following feedback frame contains the information
about motor current, encoder and motor temperature:
Table 3.3.5 Feedback of Steering Motor Information
Command Name
No.1 Motor Drive Information Feedback Frame
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Steer-by-wire
chassis
Decision-making
control unit
0x201
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
No. 1 drive current
higher 8 bits
unsigned int16
Actual current X 10 (with an accuracy of
0.1A)
byte [1]
No. 1 drive current
lower 8 bits
byte [2]
No. 1 drive
rotational speed
higher 8 bits
signed int16
Actual motor shaft velocity (RPM)
byte [3]
No. 1 drive
rotational speed
lower 8 bits
byte [4]
No. 1 hard disk
drive (HDD)
temperature
signed int8
Actual temperature (with an accuracy of
1℃)
byte [5]
Reserved
--
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
Command Name
Left Rear Motor Drive Information Feedback Frame
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Steer-by-wire
chassis
Decision-making
control unit
0x202
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
No. 2 drive current
higher 8 bits
unsigned int16
Actual current X 10 (with an accuracy of
0.1A)
byte [1]
No. 2 drive current

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lower 8 bits
byte [2]
No. 2 drive
rotational speed
higher 8 bits
signed int16
Actual motor shaft velocity (RPM)
byte [3]
No. 2 drive
rotational speed
lower 8 bits
byte [4]
No. 2 hard disk
drive (HDD)
temperature
signed int8
Actual temperature (with an accuracy of
1℃)
byte [5]
Reserved
--
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
Command Name
Right Rear Motor Drive Information Feedback Frame
Sending node
Receiving node
ID
Cycle (ms)
Receive-timeout
(ms)
Steer-by-wire
chassis
Decision-making
control unit
0x203
20ms
None
Data length
0x08
Position
Function
Data type
Description
byte [0]
No. 3 drive current
higher 8 bits
unsigned int16
Actual current X 10 (with an accuracy of
0.1A)
byte [1]
No. 3 drive current
lower 8 bits
byte [2]
No. 3 drive
rotational speed
higher 8 bits
signed int16
Actual motor shaft velocity (RPM)
byte [3]
No. 3 drive
rotational speed
lower 8 bits
byte [4]
No. 3 hard disk
drive (HDD)
temperature
signed int8
Actual temperature (with an accuracy of
1℃)
byte [5]
Reserved
--
0x00
byte [6]
Count parity bit
(count)
unsigned int8
0 - 255 counting loops, which will be
added once every command sent
byte [7]
Parity bit
(checksum)
unsigned int8
Parity bit
Note 4: The data parity bit is the last valid byte in the data segment of each frame of CAN

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message. Its checksum is calculated as follows: checksum =(ID_H + ID_L + data_length+
can_msg.data[0] + can_msg.data[1] + can_msg.data[2] + can_msg.data[3] +
can_msg.data[4]+ …+ can_msg.data[n]) & 0xFF:
•ID_H and ID_L are respectively higher 8 bits and lower 8 bits of a frame ID.For example,
if ID is 0x540, the corresponding ID_H is 0x05 and ID_L is 0x40;
•Data_length refers to the valid data length of a data segment in one frame of CAN message, which
includes the checksum byte;
/**
* @brief CAN message checksum example code
* @param[in] id : can id
* @param[in] *data : can message data struct pointer
* @param[in] len : can message data length
* @return the checksum result
*/
staticuint8 Agilex_CANMsgChecksum(uint16 id,uint8*data,uint8 len)
{
uint8 checksum =0x00;
checksum =(uint8)(id &0x00ff)+(uint8)(id >>8)+ len;
for(uint8 i =0; i <(len-1); i++)
{
checksum += data[i];
}
return checksum;
}
Figure 3.1 CAN Message Check Algorithm
•can_msg.data[n] is the specific content of each byte in the valid data segment; the count
parity bit needs to participate in the calculation of checksum, but the checksum itself does
not participate in the calculation.
3.3.2 CAN cable connection
2 aviation male plugs are supplied along with HUNTER as shown in Figure 3.2. Users need to lead
wires out by welding on their own. For wire definitions, please refer to Table 2.2.

AgileX robotics (Dongguan) Co., Ltd.
19
Figure 3.2 Schematic Diagram of Aviation Male Plug
Note: In the current HUNTER version, only the top interface is open to external extension. The
maximum achievable output current is typically around 5 A.
3.3.3 Implementation of CAN command control
Correctly start the chassis of HUNTER mobile robot, and turn on DJI RC transmitter. Then, switch
to the command control mode, i.e. toggling S1 mode of DJI RC transmitter to the top. At this point,
HUNTER chassis will accept the command from CAN interface, and the host can also parse the
current state of chassis with the real-time data fed back from CAN bus. For the detailed content of
protocol, please refer to CAN communication protocol.
3.4 Firmware upgrades
The RS232 port on HUNTER can be used by users to upgrade the firmware for the main controller
in order to get bugfixes and feature enhancements. A PC client application with graphical user
interface is provided to help make the upgrading process fast and smooth. A screenshot of this
application is shown in Figure 3.3.
Upgrade preparation
•Serial cable X 1
•USB-to-serial port X 1
•HUNTER chassis X 1
•Computer (Windows operating system) X 1
Upgrade procedure
•Before connection, ensure the robot chassis is powered off;
•Connect the serial cable onto the serial port at rear end of HUNTER chassis;
•Connect the serial cable to the computer;