Tech for a Connected Sky
The pace of commercial drone innovation continues to accelerate. Helping system developers keep up, technology vendors are providing a wide range of communications and control products to improve the capabilities of the drone designs themselves and the comms infrastructure connecting them.
For commercial drones, communications and control technologies continue to evolve as stakeholders demand ever more sophisticated functionality from drone-based systems. The innovations in these areas over the past 12 months indicate that drones are operating more as part of systems rather than stand-alone platforms.
Certainly, drones are built using numerous technologies, including everything from cameras to power solutions. But, in this article, we’re focusing specifically on communication and control solutions used in drone system designs. Such technologies include powerful wireless radio modules, high-performance AI modules, autonomous flight plan software and more.
FLIGHT CONTROL TOOL
One area of commercial drone control technology that’s particularly significant are the tools for managing remote control of drones, including both remote manual control and autonomous flight tools. A leading solution along those lines is the DroneSense Platform from DroneSense. Over time, DroneSense has added support for several different drone models. In November, for example, DroneSense added support for the entire Autel EVO Series–EVO, EVO II, EVO II Pro and EVO II Dual—in the DroneSense Platform. This integration provides customers the full suite of DroneSense capabilities when flying EVO drones, including flight control, automated flight logs, live video streaming and more.
The DroneSense Mobile flight control application provides a consistent interface across all drone models and manufacturers it supports. DroneSense customers can add an Autel EVO II Dual to their existing fleet with very little additional training to learn how to successfully operate their new drone.
Live video streaming and scene management via Operations Hub and hardware management on the administrative side will look similarly familiar for DroneSense users adding EVOs to their fleet (Figure 1). According to DroneSense, the Autel EVO aircraft responds just like any other drone in the DroneSense Platform and integrates seamlessly into users’ existing workflows.
The DroneSense platform includes a mobile app that can be used with the most popular flight controller displays, including iPad, iPhone, Crystal Sky and Smart Controller. The Operations Hub in the platform can enable users such as first responders with a mobile device or tablet to securely collaborate in missions as “boots on the ground” assets alongside drone pilots. All mobile and live drone video feeds are tracked on a map and appear in the Operations Hub simultaneously. For system administrators, DroneSense is a full system of record for the entire drone program that provides accountability and transparency across an organization. Admins can organize people, hardware, flight activity and more in an intuitive interface.
5G DRONE PLATFORM
Integrating communications and control functionality into your drone design can be a complex challenge. Smoothing the way, there are now complete platform solutions that drone designers can use that have all kinds of comms and control technologies built in. Along just such lines, last Summer Qualcomm announced its Qualcomm Robotics RB5 platform, a system designed specifically for robotics, but also well suited for drones. The product follows its previous Robotics RB3 platform, which has enjoyed broad adoption in a wide array of robotics and drone products, says the company.
The Qualcomm Robotics RB5 platform is comprised of a set of hardware, software and development tools. The Qualcomm Robotics RB5 platform was designed to meld Qualcomm’s expertise in 5G and AI to empower developers and manufacturers to create the next generation of high-compute, low-power robots and drones (Figure 2).
The platform’s Qualcomm QRB5165 processor, customized for robotics applications, offers a heterogeneous computing architecture coupled with the 5th-gen Qualcomm AI Engine, delivering 15 tera operations per second (TOPS) of AI performance for running complex AI and deep learning workloads. The processor also offers ML inferencing at the edge under restricted power budgets using the new Qualcomm Hexagon Tensor Accelerator (HTA), an image signal processor (ISP) with support for seven concurrent cameras and a dedicated computer vision engine for enhanced video analytics (EVA).
For connectivity, the Qualcomm Robotics RB5 platform supports long-range Wi-Fi and Wi-Fi 6 (802.11ax), Bluetooth 5.1, 4G and 5G. With support for 4G and 5G connectivity speeds via a companion module, the Qualcomm Robotics RB5 platform is expected to pave the way for the proliferation of 5G in robotics and drones. The solution is available in multiple options, including commercial and industrial-grade temperature ranges and an option for extended lifecycle until 2029.
Software support for the RB5 Development Kit includes Linux, Ubuntu and ROS 2, as well as pre-integrated drivers for various cameras, sensors and 5G connectivity. It also provides support for OpenCL, OpenGLES and OpenCV. The development kit includes support for the Intel RealSense Depth Camera D435i and Panasonic TOF Camera to provide depth-sensing capabilities. Thanks to Qualcomm’s strategic collaboration with TDK, the kit integrates TDK’s 6-axis, high performance ICM-42688-P IMU, accompanied by an ICP-10111 barometric pressure and a T5818 Digital (PDM) bottom port microphone.
One proven method for providing communication capabilities among multiple drones is mesh networking. Rajant offers a solution that uses a combination of wireless network nodes that Rajant calls Breadcrumbs and its InstaMesh networking software, Rajant’s Kinetic Mesh networks. These provide any-node to any-node capabilities to continuously and instantaneously route data via the best available traffic path and frequency—for any number of nodes, all with extremely low overhead.
The most recent version of Rajant’s BreadCrumb line is the DX2, Rajant’s smallest and lightest BreadCrumb. DX2 units form a mesh network when used in conjunction with its LX5, ME4 and ES1 models, which operate using Rajant’s proprietary InstaMesh protocol. With one transceiver and two external antennas, the DX2 weighs 123g making it well suited for lightweight drones.
Rajant teamed up with drone company xCraft to integrate the Breadcrumb technology on xCraft’s MATRIX-R tactical drones. The MATRIX R is a line-of-sight tactical drone with a flight time of more than 40 minutes and payload capacity of over four pounds. This drone comes with an integrated Rajant InstaMesh Breadcrumb radio and a 4K gimbaled camera with 3.5x zoom. Several optional payloads are available, including Velodyne LIDAR as well as thermal, IR, EO and multispectral cameras. An SUI controller and Android tablet are included with each MATRIX R package.
Using Rajant’s DX2 Breadcrumb devices, the MATRIX R drone can perform air-to-air and air-to-ground communication and can be seamlessly incorporated into an existing Rajant network to enable live-streaming and edge processing via aerial applications (Figure 3). Drone applications for this solution are applicable to all markets, including military, mining, oil/gas, utilities, public safety, agriculture and many others, says Rajant.
MIMO FOR HIGH BANDWIDTH
Not all drone communications requirements are the same. Some drone applications require high-bandwidth. For its part, Silvus Technologies provides communications solutions for high bandwidth video, command/control, health and telemetry data. In October, Octopus ISR Systems, a brand of UAV Factory, announced a portable high-performance automatic tracking antenna system that features MN-MIMO technology for high bandwidth, meshed video, voice and data communications through Silvus’ StreamCaster tactical radios (Figure 4).
According to Octopus ISR Systems, Silvus’ Mobile Networked MIMO (MN-MIMO) is a state-of-the-art waveform that solves many of the problems facing today’s wireless systems. The Silvus waveform is a blend of Coded Orthogonal Frequency Division Multiplexing (COFDM), Multiple Input Multiple Output (MIMO) antenna techniques and Mobile Ad Hoc Networking (MANET) to deliver digital communications with high performance and flexibility.
The company says its integration of Silvus’ MN-MIMO technology provides secure high-speed and long-range communications and surveillance capabilities suitable for harsh and dynamic environments. It enables reliable high speed self-healing and self-forming mesh network communications for drones and manned aircraft applications. Tracking antenna MIMO techniques include spatial multiplexing, space-time coding, and TX/RX beamforming, which enables excellent high-throughput communication at a range of over 100km. The operational frequency bands available range from 400MHz to 6GHz.
The system’s rugged and durable design includes an environmentally sealed heavy-duty pan-tilt unit and supports operations in all weather conditions. The tracking antenna system relies on an automatic tracking algorithm, automatic azimuth calibration and 360-degree rotation. The tracking antenna system’s portable and lightweight design ensures easy transportation. The system’s weight with tripod is only 43kg. Depending on the dish size for the selected frequency band, the entire system typically fits in one shippable military grade transportation case.
ANTENNAS FOR DRONES
Because of their strict size and weight design budgets, all electronics aboard a commercial drone have to be as small and light as possible. This applies to the antennae aboard drones as well. Feeding such needs, Octane Wireless (formerly Pharad) provides a family of drone antennae based on its proprietary Peel & Stick Appliqué antenna technology. The design of the L-, S- and C-band antenna was optimized for Mobile Ad Hoc Networking (MANET) radios operating in both licensed and unlicensed Military, Federal, Broadcast Auxiliary Service (BAS), and Commercial bands. Octane Wireless’ L-, S-, and C-band Peel & Stick Appliqué antenna offers an electromagnetically efficient radiating solution for a variety of applications, including drone datalinks and covert vehicle communications.
Octane Wireless’ portfolio of Peel & Stick Appliqué antennas provide a high-quality radiating solution, while still being nearly as thin as a piece of paper (less than 10 mils thick) and also very lightweight—weighing less than 1oz (Figure 5). A durable one-time use pressure sensitive adhesive on one side of the radiator allows the Octane Wireless Peel & Stick Appliqué antenna to adhere to the surface. The application process takes only seconds to complete.
Octane Wireless’ Peel & Stick Appliqué antennas for mini-UAV and drone applications operate over the frequency ranges of 30 MHz to 10 GHz. The Appliqué antennas are suitable for non-carbon fiber composite UAVs such as those constructed of fiberglass, Kevlar, or polypropylene; common materials for drones.
For high-speed, long range communications, datalink modules are a key technology for drones. It’s a challenge to be able to enable long-range communication from a drone, and still keep it to a small solution that’s easy to embed on a commercial drone. Aiming at just such needs, Microhard Systems provides its pMDDL1621 module, a tri-frequency MIMO(2X2) Digital Data Link (Figure 6). The pMDDL1621 Digital Data Link is a miniature OEM, high power, 2X2 MIMO wireless OEM solution.
The miniature, lightweight and robust design allows the pMDDL1621 to be an ideal candidate for size-sensitive applications like drones. The high speed, long range capabilities of the pMDDL1621 allow for high quality wireless video and telemetry communications. This digital data link provides a robust and secure link in the 1.6, 1.8 or 2.0 GHz frequency bands. The pMDDL1621 uses Maximal Ratio Combining (MRC), Maximal Likelihood (ML) decoding and Low-Density Parity Check (LDPC) to achieve robust RF performance.
The pMDDL1621 supports point-to-point, point-to-multipoint and mesh communications. It can be used in Master, Remote and Relay modes and can perform simultaneous IP and serial data networking. The device features dual Ethernet ports (LAN/WAN) and supports Port Forwarding, ACL (access control lists) and firewall. Extended temp (-40°C to +85°C) and 256-bit AES encryption is supported. The pMDDL1621 is configurable via local console, telnet, web browser and can to do local/remote firmware upgrades.
LOW POWER, NARROW BAND
Providing a radio solution that meets low power, narrow band needs, last Summer, Saelig announced the Circuit Design LMD-401 RF Transceiver Module. It is certified to FCC Part 90 in the US and ISED RSS-119 in Canada. The LMD-401, a successor to the successful LMD-400-R, is a compact integrated module with the long-range transmission and excellent interference rejection characteristics demanded for today’s battery-operated devices such as drones (Figure 7).
The LMD-401 is pin- and performance-compatible with the LMD-400-R, but provides reduced current consumption and a greater operating temperature range. Users can set operating frequencies in 12.5kHz steps within the 458MHz to 462.5MHz band, now with improved RF output flatness up to 10mW. Receiver performance includes superior interference rejection characteristics that meet the highest European EN300220 receiver standard, category 1.
The LMD-401 is designed to have low spurious emissions and excellent interference rejection capabilities, with sensitivity to -116dBm. Users can expect stable operation, even in a site where multiple radio units are being operated simultaneously. All high-frequency circuits are enclosed inside a robust housing to provide exceptional resistance against shock and vibration. Using a TCXO as the reference oscillator circuit ensures high frequency stability over a wide temperature range.
Operating voltage is 3.0V to 5.5V and operating temperature range is -20°C to +65°C. The LMD-401 RF transceiver is made by Circuit Design, Inc. (CDI), a leading Japanese supplier of low-power radio modules. The LMD-401 is available now from CDI’s US technical distributor Saelig.
AI COMPUTING IN DRONES
The idea of adding more computing intelligence on board a commercial drone is nothing new. Several applications can benefit from more autonomous decision making happening on the drone, eliminating the need to control its every move remotely. This calls for edge AI levels of computing, but in solutions compact enough to suit the design requirements of drones. Aetina serves just such needs with its NVIDA GPU-based modules.
In September, Aetina announced its new AN810-XNX edge AI computer leveraging the capabilities of the Nvidia Jetson Xavier NX. This edge AI computer provides various alternatives of I/O slots, expanding Aetina’s range of edge AI systems built on the Jetson platform for robotics, drone, UAV and other applications.
The AN810-XNX combines the Nvidia Jetson Xavier NX and Aetina AN810 carrier board in a Nano-ITX form factor of 120mm × 120mm × 47.3mm (with fan) (Figure 8). It supports full M.2 slot with M-key, E-key, and B-key and the interface with PCIe/SATA/USB 3.2 Gen2/USB 2.0. AN810-XNX features prospective communication capabilities. Since 5G technology has become critical for IoT applications, AN810-XNX is integrated with a 4G/5G module for high-speed wireless connection and data transferring.
Meanwhile, AN810-XNX is equipped with an onboard SIM slot and the Innodisk InnoAGE out-of-band management SSD solution through M.2. The SSD solution reduces the massive cost of manually repairing the edge device and minimizes the equipment’s downtime, making remote control of the edge device more convenient.
Serving the needs of vision AI applications, the AN810-XNX supports the single 120-pin connector for a MIPI CSI-2 interface. It can handle intensive AI workloads of ultra-high-resolution cameras to perform more accurate image analysis. For backup support, Aetina offers BSP and DTB configuration updates for both standard and customized platforms in their service policy.
Another company providing an AI edge module based on the Nvidia’s Jetson SoMs (systems on modules) is Mistral Solutions. In October, Mistral launched its Neuron Base Boards, a family of product development solutions for Nvidia’s Jetson Nano and Jetson Xavier NX SoMs. The Neuron Base is designed to enable all the functional features of Nvidia Jetson SoMs and aid faster product development and prototyping. The Neuron platform is well suited for realizing AI-based machine vision applications such as edge cameras with object detection and recognition, human activity recognition, robotics, drones, autonomous navigation, radar-camera sensor fusion and smart retail among others.
The Neuron Board is available in two variants: NB Basic and NB Turbo (Figure 9). The NB Basic brings out the basic required interfaces and connectivity of the Jetson SoM like Ethernet, CSI, USB, HDMI, M.2 M, mmWave RADAR etc. The NB Turbo is richer in terms of functional features and interfaces like GMSL, FPD Link III, Wi-Fi 802.11, Bluetooth, and 9-axis IMU Sensors in addition to all features of NB Basic.
The Neuron Board is complemented by a range of vision analytics algorithms that use Nvidia’s CUDA, cuDNN and TensorRT components. Mistral has partnered with INKERS, a Deep Video Processing company, to integrate these algorithms on Neuron Board, making it well suited for retail analytics, security and other AI applications.
COLLISION AVOIDANCE SOLUTION
Another critical part of drone control is collision avoidance. Drone-based collision avoidance technologies keep evolving. Interest in drones for last mile delivery, construction, agriculture, public safety, infrastructure inspection and others has grown steadily in recent years. To ensure reliable and safe operation of drones in these and other applications, you need the right sensors.
For its part, Ainstein provides a module called the SRD-D1 that provides collision avoidance radar for drones (Figure 10). The device operates over a frequency range of 24GHz to 24.25GHz with a range accuracy 0.6m and a detection range of 1.8m to approximately 30m. About the size of an old iPhone 5, the module is 116mm × 81mm × 25mm in size and weighs less than 200g.
SRD-D1 represents Ainstein’s latest generation airborne object detection radar. It can enable drones to detect and avoid buildings, vehicles, tree branches, light poles, ground surfaces (in agriculture applications) and more. You can position multiple SRD-D1 modules on your drone to achieve 4 or 5 directions of obstacle sensing and avoidance. It supports horizontal or vertical angle measurement, which gives you the precise 2D location of the obstacle. Built with a rugged design, the SRD-1 doesn’t experience degradation in performance under low-light, rainy, dusty, foggy or other similar conditions.
PAYLOAD DEV KIT
Although DJI is itself a leading drone manufacturer, the company also supplies a rich set of hardware and software products aimed at helping drone system developers create their payload systems and other customized drone products. To help developers develop the payload, DJI provides Payload SDK (PSDK), X-Port and SkyPort to enable developers to obtain resources from DJI drones, such as power and status (GPS, attitude, time and date) (Figure 11). In February, DJI released V2.2.1 of the PSDK. PSDK not only provides the API and hardware for developing the payload, but also provides standards, technical support, marketing and ecological cooperation services.
DJI offers two physical devices to integrate your payload onto DJI drones. One is the DJI SkyPort V2, a standard adapter that secures and integrates a payload onto the drone, facilitating communications between these two systems (Figure 12). The other is the DJI X-Port, a ready-to-build standard gimbal that comes with DJI SkyPort V2 and a gimbal debugging interface. Inclusion of a gimbal reduces payload-to-drone integration.
The PSDK’s communication APIs form a new set of protocols that let your payload communicate with the drone’s internal systems such as flight controller, GPS module, transmission system and more. Developers can build from the ground up using two available integration ports designed to help you connect your payload onto DJI drones. Sensors across all sections of the electromagnetic spectrum, robotic tools and other tools can be mounted onto a DJI platform.
Using the SDK’s mobile app DJI Pilot, you visualize the data from your payload in real time and send commands, adjust settings and more through the DJI Pilot app or a custom-built mobile application. The DJI Pilot is compatible with payloads, which are developed using PSDK. And DJI provides Mobile SDK to help developers to develop Mobile apps to control the payload. Also provided is Onboard SDK, which helps developers write the self-control programs and Windows SDK that helps developers to craft data analyzing software.
Aetina | www.aetina.com
Ainstein | www.ainstein.ai
DJI | www.dji.com
DroneSense | www.dronesense.com
Microhard Systems | www.microhardcorp.com
Mistral Solutions | www.mistralsolutions.com
Nvidia | www.nvidia.com
Octane Wireless | www.octanewireless.com
Octopus ISR Systems | https://octopus.uavfactory.com
Qualcomm | www.qualcomm.com
Rajant | www.rajant.com
Silvus Technologies | www.silvustechnologies.com
PUBLISHED IN CIRCUIT CELLAR MAGAZINE • MAY 2021 #370 – Get a PDF of the issueSponsor this Article
Jeff served as Editor-in-Chief for both LinuxGizmos.com and its sister publication, Circuit Cellar magazine 6/2017—3/2022. In nearly three decades of covering the embedded electronics and computing industry, Jeff has also held senior editorial positions at EE Times, Computer Design, Electronic Design, Embedded Systems Development, and COTS Journal. His knowledge spans a broad range of electronics and computing topics, including CPUs, MCUs, memory, storage, graphics, power supplies, software development, and real-time OSes.