Dagu Wild Thumper 4WD All-Terrain Chassis

by Pololu

This rugged, 4-wheel-drive chassis from Dagu Electronics has independent suspension for each of its spiked 120mm-diameter wheels, allowing exceptional traction over uneven terrain

Its body is made from 2mm-thick anodized aluminum with a 10mm-pitch grid of 4mm holes, making it easy to mount electronics and accessories to the chassis. Assembly of the chassis is a simple three-step process that takes just minutes. This model is black with metallic-red hubs.

This rugged, 4-wheel-drive chassis from Dagu Electronics is a smaller version of the Wild Thumper 6WD chassis. It is designed to excel at traversing rough terrain, making it a great platform for any robot that needs to perform tasks in a complex outdoor environment. It features four powerful DC motors with brass brushes and 34:1 or 75:1 steel gearboxes that drive large (120mm diameter) spiked tires, and a unique “super-twist” suspension system acts to keep each wheel in contact with the ground for maximum traction, even when driving over uneven or bumpy surfaces. The suspension can be adjusted to suit different loads and conditions. The chassis is made from a 2mm-thick corrosion-resistant anodized aluminum plate, all of the nuts, bolts, and screws are stainless steel, and the brass fittings and suspension springs are nickel-plated.

When powered at 7.2 V, the version of the chassis with 34:1 gearboxes can reach a top speed of approximately 7 km/h (4.5 mph), and each motor has a stall torque of roughly 5 kg-cm (70 oz-in). At the same voltage, the version of the chassis with 75:1 gearboxes can reach a top speed of approximately 3 km/h (2 mph), and each motor has a stall torque of roughly 11 kg-cm (150 oz-in).

Using the Chassis

The chassis’ aluminum plate has 4mm holes spaced every 10mm, providing plenty of options when it comes to mounting your control electronics, sensors, and additional hardware. A compartment in the chassis has been designed to hold 7.2 V sub-C battery packs (not included) that are commonly used in RC cars. Two such battery packs can fit in the compartment. The interior of the chassis also features convenient screw terminals for connecting your battery and motor driver leads. The motor leads are pre-connected to these screw terminals.

This is a differential-drive chassis, meaning that turning is accomplished by driving the motors on the two sides of the platform at different speeds. The two motors on each side of the robot are wired in parallel, so only two channels of motor control are required to get this chassis moving. The motors are intended for a maximum nominal operating voltage of 7.2 V (2 V minimum), and each has a stall current of 6.6 A and a no-load current of 420 mA at 7.2 V. Since the motors will briefly draw the full stall current when abruptly starting from rest (and nearly twice the stall current when abruptly going from full speed in one direction to full speed in the other), we recommend a motor driver capable of supplying the 14 A combined per-channel stall current of these motors at 7.2 V.

Specifications

  • Size: 280 × 300 × 130 mm (11" × 12" × 5")
  • Weight: 1.9 kg (4.1 lb)
  • Ground clearance: 60 mm (2.5") when lightly loaded
  • Recommended motor voltage: 2 V to 7.5 V
  • Stall current at 7.2 V: 6.6 A per motor
  • No-load current at 7.2 V: 420 mA per motor
  • No-load output shaft speed at 7.2 V:
    • 350 RPM for the version with 34:1 gearboxes
    • 160 RPM for the version with 75:1 gearboxes
  • Stall torque at 7.2 V:
    • 5 kg-cm (70 oz-in) per motor for the version with 34:1 gearboxes
    • 11 kg-cm (160 oz-in) per motor for the version with 75:1 gearboxes

If you are looking for a bigger robot that is better at scaling inclines and traversing larger obstacles, please consider one of the Wild Thumper 6WD models

The higher gear ratio version has a lower top speed but can produce greater torque. Note that while the Wild Thumper 4WD chassis includes four wheels, the wheels can be purchased in pairs for use as replacement Wild Thumper parts or as wheels for custom chassis. The wheels are available with metallic-red hubs and chrome-colored hubs.

Why not try it with Yukon?

Looking for a controller for your project? Yukon is a high-power modular robotics and engineering platform, built around RP2040 and designed to drive the most ambitious robots, props and devices.

Yukon is a standalone controller that can be equipped with up to six interchangeable modules capable of driving high-powered hardware - this is made possible by the unique pin capabilities of Raspberry Pi's multitalented RP2040 chip. This flexibility means you can drive many unique combinations of motors, servos, steppers, speakers, LED strips and more, all from a single Yukon host!