Safety first in mining and tunnelling
For this reason, the German machine manufacturer GHH Fahrzeuge GmbH, Gelsenkirchen, is pushing the use of radio remote controls whereever it suits the application. Its T-RX100J model (Figure 1) is particularly light, comparatively inexpensive and also works with other OEM equipment. It can be used to control heavy equipment by radio remote, from a safe distance, including load haul dumpers, dump trucks and drilling rigs. It is recommended for use in aeras where the operator would be exposed to increased danger. Some key applications include sublevel stoping, because of rock instability, as well as block cave, due to the potential for rock burst.
The control unit weighs only about 1,200 g. It is hooked into a central neck strap. The ergonomic housing is made of impact-resistant plastic and protected against dust and water according to IP67. Two programmable joysticks and switches for all common machine functions are available to the operator. An LCD display shows parameters such as temperature and oil level.
A special feature is the tilt sensor. If the control unit tilts unexpectedly, e. g., because the operator falls, the dead man switch stops the machine. The degree of response can be changed to meet individual requirements. The safety circuit also triggers if the radio connection is interrupted. Communication with the machine is digital and therefore highly stable. For failure protection, the RRC uses twin processors with self-diagnosis function. A large emergency stop switch is located in the middle of the console. The overall ergonomics are exemplary.
On the machine side, a receiver box with aluminium housing is installed. At 1,600 g it is also very light and compact, and also extensively protected. The connection is made via analogue and digital interfaces, with radio channels in MHz and GHz bands. The operating range is –25 to 70 °C. As an option, a video function can be added. A motion picture is send via Wifi transmission from a camera on the maschine to a screen clipped onto the RRC. This option may be used to recover machines from stopes with a tele-remotely controlled LHD.
GHH sells the remote controls in increasing numbers. The latest customer is a mining contractor in Chile who uses it to remotely control his load haul dumpers (competitive model), in an underground mining application. The control system is adapted by GHH to the requirements of the operator and the machine, tested and handed over after instruction.
Source: GHH Fahrzeuge