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97 Clearpath Robotics Jackal | Digest Performance, payload and stability A top speed of 2 m/s (7.2 kph) preserves safety and stability, and is probably as fast as most Clearpath customers would want the vehicle to drive autonomously, Edwards notes. “We didn’t have hard requirements for things such as endurance, ability to climb gradients and payload. We tried to get the most we could while optimising the trade-offs between cost, complexity and performance.” With payload, for example, the 20 kg quoted maximum is not a hard limit, he says, more of a reference point indicating where the vehicle might start to become unstable or difficult to work with on outdoor terrain. Payload facilities and future development The list of sensors, manipulators, comms, navigation and computing devices that have been installed on Jackal is a long one. Clearpath can generally integrate anything that falls within the Jackal’s size, weight and power limits, Edwards says, while customers often integrate their own, many of which are prototype devices that support their research. The Jackal accommodates its payloads using physical, electrical and data interfaces. For example, the payload interface plates on top of the platform are simple metal sheets that can be drilled with bolt patterns to suit different pieces of equipment. Wiring is either passed through the foam gasket under the plate or terminated using waterproof connectors into the chassis. Internally, the vehicle has Molex connectors and screw terminals for user power, while the PC is positioned to ease access for USB, Ethernet, RS-232 and other data connections. Although the Jackal is a mature platform, Clearpath continues to offer and support new sensor and payload options and keeping the computing network equipment up to date, Edwards says. New releases of the operating system are installed when they are shown to be stable and well-supported by the ROS community. In the near future, the company plans to broaden the Jackal’s appeal to users who may not be familiar with programming or ROS by offering new software, including outdoor navigation and teleoperation packages, that can be run through a simple GUI. Unmanned Systems Technology | April/May 2020 Dimensions: 508 x 430 x 250 mm Weight: 17 kg Payload: 20 kg (maximum), 10 kg (all terrain) Maximum speed: 2 m/s (7.2 kph) Ground clearance: 65 mm Operating time : 8 hours maximum, 2 hours typical Drive power: 500 W Battery: lithium-ion User power: 5 V @ 5 A, 12 V @ 10 A, Vbat (24 V norm) @ 20 A Encoders: 78,000 pulses/m, quadrature Comms: Ethernet, USB 3.0, RS-232, IEEE 1394 Driver/APIs: packaged with ROS Control modes: open loop, wheel velocity, kinematic commands Feedback: battery plus motor, current wheel velocity, integrated GPS, gyroscope and accelerometer Some key suppliers Battery: All Cell Technologies BMS: All Cell Technologies Cameras: Axis Communications Cameras: FLIR Systems Lidars: Hokuyo Lidars: Sick Lidars: Velodyne Emergency stop: HRI Manipulators: Kinova Radio: Microhard Inertial measurement unit: Microstrain Motors: Midwest Motion Electrical connectors: Molex GPS: NovAtel GPS: Swift Navigation Computing hardware: Nvidia Indoor navigation software: Otto Motors Wireless charging: Wibotic Specifications The Jackal rolls on 8 in tyres, and manoeuvres using skid steering. It also needs neither suspension nor mechanical brakes