Hardware

The main focus when developing James was to make a robot that can guide users to specific locations.

James will interact with the user using the tablet and the microphones and speakers installed in the head and body of the robot. James will also continuously scan the environment using the SLAM-system installed in the base of the robot.

Specifications

General

James has the following specifications:

Dimensions

420 mm x 420 mm x 800 mm (LxWxH)

Weight

17 kg (including the packaging)

Base station

240 mm x 85 mm x 95 mm (LxWxH)

Operating temp

0 - 40 °C

Operating humidity

20 - 90%

Maximum operating time

9 à 12h

Tablet

The tablet mounted in the "head" of James has the following specifications:

CPU Model

MSM8953

Number of cores

8 (Qualcomm MSM8953)

Clock speed

2.0 GHz

RAM

3 GB

Internal Storage

32 GB

Touch-screen

10" capacitive high sensitivity screen

Camera-resolution

13 MP

Peripherals

The following peripherals have been connected to the tablet:

Name

Description

Location

Microphone array

6 microphone ring-array

At the top of the robot

Speaker

5W hifi speakers (x2)

At the side of the main body

Features

The peripherals contain the following specifications:

Audio-detection range

360°

Echo cancellation

Supported (available)

Speech enhancement

Supported (available)

Voice wake-up

Supported (available)

Connectivity

James can connect to other devices using the following specifications:

WIFI

2.4G / 5G Dual Band (802.11 b/g/n)

4/5G

Unsupported

Bluetooth

Bluetooth Version 4.0

Wifi specifications

The wifi-router (installed in the main body of the robot) has the following specifications:

Chipset

MT7628AN + MT7612E

Main frequency

580MHz

Wireless transmission rate

1167Mbps

2.4GHz channel selection

1-13

2.4GHz channel bandwidth optional

20M 40M

5GHz channel selection

36 40 44 48 149 153 157 161 165

5GHz channel bandwidth optional

20M 40M 80M

SLAM

The SLAM-system in the base of the robot has the following specifications:

Lidar

Bumpers

2 (at the side of the base)

Scanner

1 (scanning to the front)

Power connector

1 (at the back of the base)

Power button

1 (at the back of the base)

Microswitches (1)

2 (at the back)

IR-detector (1)

1 (at the back)

Wheels

Omnidirectional
Tripod configuration

(1): These are needed to make the robot dock with the charging station.

An on/off-switch is present at the bottom of James to disable the front scanner. Turning this switch on will disable the front scanner. Disabling the front scanner will cause the objects below the scanned surface of the Lidar to no longer be detected in front of James. The lidar will still detect the objects, regardless of state of the front scanner.

Lidar

The installed Lidar-unit has the following specifications:

Item Unit Min Typical Max Comments

Distance range

Meter (m)

0.15

-

8

Based on white objects with 70% reflectivity

Angular range

Degree

0

-

360

Distance Resolution

mm

-

<0.5

-

<1.5 meters

Sample Frequency

Hz

2000

8000

8010

Sample Duration

Millisecond(ms)

-

0.125

-

-

Scan Rate

Hz

5

10

15

The rate is for a round of scan. The typical value is measured when RPLIDAR takes 400 samples per scan.

Laser wavelength

Nanometer(nm)

775

785

795

Infrared Light Band

Laser power

Milliwatt (mW)

-

3

5

Peak power

Pulse length

Microsecond (us)

60

87

90

-

Battery

The battery installed in James has the following specifications:

Type

Lithium-Ion 18650

Voltage

14.4V

Capacity

13Ah

Energy

187.2 Wh