MExRover - the research platform

Перейти на русскоязычную версию раздела сайта

Automation of various processes significantly increases the efficiency of the solution not only for ordinary tasks, but also for various scientific experiments and studies. Project Rover, developed in such KB Merlin under the leadership and on the job MExLab, is one such example. The Rover is a versatile modular self-propelled wheeled platform for research, metric stereophotomaker areas and the simulation of the performance of various tasks.

The Rover consists of two main parts: a six-wheeled mobile platform, including control systems and software package, and the lifting of the boom carrying the camera equipment and sensors and sensors for VARIOUS PURPOSES. The purpose was to create a wheeled apparatus, the Autonomous moving on a terrain that is designed for a wide range of tasks associated with studying the surrounding terrain, the layout of which could vary depending on study objectives. Thus, the device must be easily modifiable and for this purpose be constructed on the modular principle, the most flexible, unified solutions for a wide range of tasks, therefore it was created in a modular fashion. So the body of the Rover is a frame on which there are special hatches used for equipment mounting. Either component can be replaced in a matter of minutes, which is enough to dismantle the necessary hatch.

Link suspension of the wheel hubs had been unification: all levers interchangeable in pairs (left and right), which minimizes the number of spare parts for rapid repair Rover. For movement of the platform used the so-called "motor-wheel" (the motor is combined with a wheel), which use high-precision stepping motors with power reducers, ensuring supply thrust sufficient to overcome major obstacles. The maximum speed of the platform is 5 km/h, and the application of energy saving technologies provides a range of 5-10 km depending on speed. Due to the fact that rotary are 4 of the 6 wheels, the Rover has a high maneuverability - the minimum turning radius is 2 meters on an external gabarretta stepper motors is beneficial to positioning accuracy of the platform - the theoretical minimum movement step only 0.4 mm.

The maximum suspension travel is approximately 250 mm, which allows to easily overcome even relatively large irregularities of terrain. It is possible to install to a forest of different diameters with different characteristics of the tread. The use of hydraulic shock absorbers provides a smooth ride, necessary for the effective operation of measuring and survey equipment. If necessary you can quickly change the stiffness of each of the 6 shock absorbers that will allow you to adjust the road clearance depending on the load on the platform. The maximum design total mass of the Rover - 50kg.

On a retractable rod of the Rover are two digital high resolution cameras to perform stereo imagery of the terrain and an additional imaging device. The main two cameras, and stereo cameras and sensors are placed on a lifting platform driven by two powerful linear motors. Two-section boom is unfolded in 20 seconds and raises the crew module to a height of 170 cm from ground level. Stabilization of the horizontal position of the imaging module using the mechanisms, including high-precision accelerometers, and linear and stepper motors, it provides an error in position of the platform is not more than 1° in all three axes. The maximum deflection angle of the imaging module on the rod X and Y is ± 30° in both directions from the Central position, that overrides any possible shooting. Additionally the survey module can be rotated around its own axis and in a plane parallel to the optical axes of the cameras.

Maximum useful load on the boom is 5 kg, considering the weight (about 2 kg) allows installing additional equipment with a total weight up to 3 kg. the rods are special channels for routing the cables. The crew module is equipped with universal mounts for additional equipment.

Control of the Rover through software-computing device on the basis of two management modules of its own design, based on the use of 32-bit Cortex M3 MCU. The first module ("controller") is responsible for the movement of the Rover and manages the channel 5 transmitter on-Board voltage, which ensures the supply of additional equipment directly through the module without building power supply units or converters. In addition, the function of the control voltage on each channel and taking into account the total energy consumption of 6 motorized wheels and all the additional equipment that is necessary for calculating remaining power reserve. The second module controls the lifting of the upper platform on the rod and its stabilization. It also includes inputs under 6 analog sensors (temperature, pressure, humidity, etc.).

To demonstrate the capabilities of the Rover master controller of the control module of its own design equipped with an interface for wireless data transmission over short distances (Bluetooth) that allows you to manage all the functionality in manual mode using special software, which in addition to control self-propelled platform you can track and all the telemetry. The main means of long-distance communication - Wi-Fi - is made using powerful transceivers. Confident communication range is 2-3 km away.

Rover with raised arrow	Rover in stowed position
Assembly of the Rover	Painting
The first "walk"	Test suspension