Mobile Controls and Control Systems for multi-axis applications
Mobile Controls and Control Systems
Conductix-Wampfler Mobile Controls type ST-89x of the LJU “Series 8” control systems are compact, programmable Mobile Controls intended for driving 1 to n motion axis. Typically, the range of drives active in parallel operation ranges up to 3. Further axis movements are often realized as sequential drives, so using an integrated Frequency Inverter first to serve the lowering and then after lowering is finished to rotate the transport good into an assembly friendly orientation. These control systems are designed for the operation and control of a defined range of motors in industrial and commercial plants. LJU Mobile Control receive action clearances via commands, transmitted by different means i.e., full and half-wave signals, PWM or data bus communication.
Control via travel commands
LJU Mobile Controls constantly evaluate the incoming commands from the system controller (e.g. via control rail) and determine the travel behaviour of the transport system by linking it to the current parameter setting locally implemented in the LJU Mobile Control Unit. In this way, different signals in different areas of the system can be used to achieve the desired travel behaviour (e.g. slow positioning speed, high transport speed, brake release, etc.). The drive motor is driven as long as the control system detects a valid signal, and no stop command is received. External sensors connected to the control systems are monitored and evaluated independently by the control systems. The necessary configuration is programmable. If a stop command is detected, the control system brings the vehicle to a complete stop. After the stop command is cancelled, the control system starts up again according to the set delay time. Building blocks to add Functional Safety are at hand on request.
Regenerative braking
To decelerate a vehicle slowly, bring it to a controlled stop and to spare the brakes, the control systems offer the option of regenerative braking. Regenerative braking by the control system is adjustable. Application software and operating parameters can be transmitted to the control system via infra-red by means of the manual programming device (MU- 705, separately available).
Status display
The control systems continuously monitor the basic conditions of the vehicle and, in the event of a fault, issue a differentiated message via the integrated display and, if used, a collective fault message is sent to the higher-level system controller via the signal rail. The control systems are equipped with a display that allows easy and clear reading of the status messages or error states.
Remote control
For functions such as manual movement of a vehicle, the control systems can be addressed by means of an infra-red hand-held remote control. Assigning parameters to the control system Defined data records can be transferred to the control system using the MU-705 manual programming device.
These data records consist of:
- Vehicle parameters
- PCM configuration tables
- Vehicle tables
Vehicle parameters and configuration switches
The vehicle parameters and configuration switches are used to set the vehicle behaviour according to the system requirements. Various additional control system functions can be activated, deactivated and set. Positive values from 0 to a maximum 65535 can be set as parameter values. The value range is limited further for some parameters.
Configuration switches are a part of the vehicle parameters. They activate or deactivate individual control system functions.
Vehicle tables
Vehicle tables contain data, which is accessed by certain control system functions. This data is assigned to the system in which the vehicle control system is used. The vehicle tables are used to set values that affect the motion and positioning functions.
PCM configuration tables
In the PCM command system, different half-wave patterns are transmitted to the vehicle control system via the PCM hardware. The vehicle control system is able to recognise these commands and adjust its behaviour accordingly. The PCM configuration table defines how the vehicle control system behaves with a PCM command.
FAQs
Frequently asked questionsHow many Axis does Multi-Axis mean exactly?
Multi-Axis does not mean a specific number of Axis. It firsthand means that there are at least 2 Axis of Movement which are active simultaneously. A typical example would be for example an EMS line, where vehicles can already start lowering the transport into a defined height while still driving forward. Typical situation when approaching an assembly workstation along the production line. If you do add a rotation of the transport good i.e. a car body for better access to the work spot, you would already be with a 3-axis solution. Naturally you could this also do with a 2 Axis control unit, but sequential than means extra time before set and ready. So, at the end the decision for how many Axis depends on multiple factors. Typically, most applications run with up to 3 Axis setups and have every extra movement than sequential. However, the sky is the limit.