On-demand electro-hydraulic steering system

A method of operating the hydraulic steering system of a machine, comprising:

• sending a first control signal from a control module to a pilot valve;
• operating the pilot valve to direct pilot fluid to a nine-way, five-position pilot operated directional spool valve in response to the first control signal;
• opening the nine-way, five-position pilot operated directional spool valve to a low pressure position in response to the pilot fluid;
• directing fluid through the nine-way, five-position pilot operated directional spool valve to a head portion of a first actuator;
• detecting resistance to actuation of the first actuator;
• comparing the detected resistance to a threshold resistance with the control module;
• sending a second control signal from the control module to the pilot valve when the detected resistance exceeds the threshold resistance;
• operating the pilot valve to direct pilot fluid to the nine-way, five-position pilot operated directional spool valve in response to the second control signal;
• opening the nine-way, five-position pilot operated directional spool valve to a high pressure position in response to the pilot fluid;
• and
• directing fluid through the nine-way, five-position pilot operated directional spool valve to the head portion of the first actuator and a rod portion of a second actuator.

A method steering a machine, comprising:

• sending a first control signal from a control module to a proportional solenoid steering pilot valve;
• operating the pilot valve to direct pilot fluid to a nine-way, five-position pilot operated directional spool valve in response to the first control signal;
• opening the nine-way, five-position pilot operated directional spool valve to a low pressure position in response to the pilot fluid;
• directing fluid through the nine-way, five-position pilot operated directional spool valve to a first actuator;
• monitoring fluid pressure within the first actuator;
• comparing the monitored fluid pressure to a threshold value with the control module;
• sending a second control signal from the control module to the pilot valve when the monitored fluid pressure exceeds the threshold value;
• operating the pilot valve to increase the pilot fluid pressure to the nine-way, five-position pilot operated directional spool valve in response to the second control signal;
• opening the nine-way, five-position pilot operated directional spool valve to a high pressure position in response to the increased pilot fluid pressure;
• directing fluid through the nine-way, five-position pilot operated directional spool valve to both the first actuator and a second actuator;
• continuing monitoring of fluid pressure within the first actuator;
• continuing comparing of the monitored fluid pressure to the threshold value;
• sending a changed control signal from the control module to the pilot valve when the monitored fluid pressure falls below the threshold value;
• operating the pilot valve to decrease the pilot fluid pressure to the nine-way, five-position pilot operated directional spool valve in response to the changed control signal;
• and
• opening the nine-way, five-position pilot operated directional spool valve to a low pressure position in response to the decreased pilot fluid pressure.