Pro­duc­tiv­i­ty increas­es through mea­sur­ing unit 

HSM (Hohen­lo­her Spezial-Maschi­nen­bau) and Gemac Chem­nitz have been part­ners in the fields of incli­na­tion sen­sors and Field­bus diag­nos­tics for many years. So it was obvi­ous that the new dynam­ic incli­na­tion sen­sor “Gemac Motus” should also be includ­ed in the devel­op­ment process of the new HSM machine generation.

At HSM, the sen­sors are used in har­vesters, for exam­ple. They must cope with adverse con­di­tions, such as strong tem­per­a­ture fluc­tu­a­tions, mois­ture, vibra­tions and heavy soil­ing from dirt and oils. One machine uses three sen­sors: one to mea­sure the slope, one on the crane and anoth­er on the cab. The crane and cab­in sen­sors are used to lev­el the com­po­nents to the zero posi­tion automatically.

The pre­vi­ous ver­sion caused problems 

With the new har­vester machine gen­er­a­tion, the goal was to make these func­tions more sta­ble regard­ing inter­fer­ence from exter­nal accel­er­a­tion and thus sig­nif­i­cant­ly increase dri­ving com­fort”, says Max Skibbe, devel­op­ment engi­neer at HSM. The main require­ment for the new sen­sor was to com­pen­sate for the inter­fer­ence from exter­nal accel­er­a­tion and thus ensure a faster response from the auto­mat­ic lev­el­ing func­tions. Anoth­er require­ment was that the sen­sor sup­port­ed the CAN pro­to­col and made the mea­sured val­ues avail­able as volt­age val­ues. It was also impor­tant to be able to adjust the volt­age range from 0.5 V to 9.5 V to be able to detect any faults in the cabling.

Solu­tion and deci­sion-mak­ing process

After select­ing avail­able prod­ucts, HSM chose the Gemac Motus. As a pow­er IMU for mobile pow­er machines, it is a sen­sor mea­sure­ment unit that can be con­fig­ured for a wide range of appli­ca­tions. It enables 6‑axis motion detec­tion. The spe­cial­ly devel­oped sen­sor fusion algo­rithm takes over the high-pre­ci­sion ori­en­ta­tion cal­cu­la­tion, sup­port­ed by sen­sor fusion fil­ters that sup­press exter­nal­ly act­ing accel­er­a­tions. “It is thus pos­si­ble to select the deter­mined (move­ment) sta­tus from exter­nal inter­fer­ence by using the para­me­ter­i­z­able algo­rithm,” says Rico Graessler, team leader for sen­sor devel­op­ment at Gemac.

The con­fig­u­ra­tion tool of the Gemac Motus opens up excel­lent oppor­tu­ni­ties to get to know and con­fig­ure the sen­sor. You can look at sig­nal curves with­out much effort, mak­ing work­ing on the pro­to­type very easy. Our expe­ri­ence here is that we are already delight­ed with the stan­dard con­fig­u­ra­tion”, says Skibbe.

Cus­tomer is satisfied 

The expe­ri­ences after six months are very pos­i­tive”, says Skibbe. “The set goals have been ful­ly achieved. There is excel­lent com­pen­sa­tion for vehi­cle accel­er­a­tion, and the auto­mat­ic func­tions can work very pre­cise­ly and quick­ly. Dri­ver com­fort was notice­ably increased, and machine pro­duc­tion increased a lit­tle. There were no break­downs.” That is why HSM will soon expand the appli­ca­tion area of Gemac Motus to include the 208F for­warder and the 805 and 904 rear tractors.

For 50 years, HSM (Hohen­lo­her Spezial-Maschi­nen­bau GmbH & Co. KG) has been a man­u­fac­tur­er of spe­cial forestry hauler, for­warders, har­vesters and forestry com­bi machines spe­cial­ly devel­oped for forestry use. The pri­ma­ry goal is to com­bine the high­est per­for­mance, durable designs and best ergonom­ics with sus­tain­able soil pro­tec­tion to main­tain the pro­duc­tiv­i­ty of the forests.