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Gearbox in innovative, hybrid Quad for the military

What are the benefits of a hybrid quad compared to a normal quad for the military?
It reduces noise, requires less fuel and is also sustainable. “Good story!”, that is what Rob Verbuggen and Mattijs Tweehuysen thought and together they founded Reeq (Range Extended Electrical Quad) to carry out the development and construction. The result is a hybrid quad with a special and extremely efficient powertrain. Apex Dynamics did a small contribution to this special project.

Gearbox in power steering transmission

Various tests have shown that the hybrid quad gives good performance, also in terms of comfort and user-friendliness, but Verbruggen has a number of other requirements. For example, they want to improve the transmission of the power steering.

Normally a worm gear transmission is used in a power steering unit. A torque sensor is then used to feed back the motor and thus determine how much torque is required. The difference with a normal car is that the steering wheel can turn 3x (1,080 degrees) and with a quad only 90 °. Therefore you need much more torque to be able to make a complete steering movement.

In the last iteration, a low-backlash AB090 gearbox from Apex Dynamics (with customized motor adapter plate) gives the desired result. The worm gearbox has been replaced by a planetary gearbox and the 50: 1 ratio provides sufficient torque for the power steering and therefore keeps the quad manageable and precisely controllable.

This already works fine, Reeq now wants to develop further and integrate the entire drive for the power steering in the steering column. In addition, they want to make remote control possible (Autonomous mode), but this requires even more torque. This will also be developed further.

Efficiency powertrain

An extensive article about the Quad of Reeq was recently published in magazine Aandrijftechniek. With attention to the efficiency of the powertrain:

“In addition to functionality, the drive concept also offers efficiency benefits. Where with a normal powertrain 20 – 25 percent losses occur, this percentage is only 2 – 3 percent with this hybrid variant (this only applies to the powertrain). In addition, the range extender also runs precisely on the highest efficiency, which means that the losses caused by transferring the energy to the battery are small. This is different with a combustion engine that actually rarely runs in its optimum working area because the load is constantly changing as a result of giving more or less acceleration in combination with the terrain. Efficiency is disadvantaged by the higher weight of this concept (around 100 kg), but due to the achieved efficiency it ultimately drives more economically and the user benefits from the advantages discussed earlier.”

Another advantageous feature of an electric power train is that the torque delivered is immediately available. This is advantageous when a quad is used on rough terrain or when speed (acceleration) is important. The concept is such that the drive of the axles is always done electrically so that the driver always has the immediately high torque available.

High torque, low speed: towing heavy vehicles

One of the ideas for the future of the Reeq quad is to use it for pulling heavy vehicles out of the hangar. Extra towing torque is required to tow heavy vehicles at “creep speed” (0~5 km/h). The power steering has shown that the servomotor with gearbox works, it would be nice if such an identical system could be used as extra torque in the drive train.

A gearbox from Apex Dynamics will offer a solution here, in the words of Rob Verbruggen

“Your gearbox is currently used in the power steering and works great. The plan is to use the same system as support in the quad transmission, as mentioned at the end of the article inside magazine Aandrijftechniek.”

These are the challenges that Apex Dynamics would like to participate in. It shows that our gearboxes are not only suitable for installation in machines (where most of our applications are located) but also for tough “off road” applications.

If you want to know more or if you have a specific challenge for which you want to know the solution Apex Dynamics would recommend? Please contact us.

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