Terrain hopper steering

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Steering

Distance between axles is 0.93 m

Distance between king pins 0.55 m

Max steering angle actual is about 32 degrees (center heading)

Steering is limited to +/- 28 degrees in RHD, this gives a turning radius of 2m.

Steering is sensed by RHD plugin "as5047x2", that receives data from encoder interface - a teensy.

The steering angle (in degrees * 10 - positive left) is then transferred to "roboteq-can" RHD plugin, where the steer controller is implemented - and limited to +/- 28 degrees.

CAD drawings

See https://cad.onshape.com/documents/97c36fb21a7a858c57c0af9f/w/0d867586bc28d7a9194d7ff3/e/ca0f539fa3eee3cfe0ed4130

Overview of new steering

Figure 1. New steering part maintaining original steering axle position, but replacing with bearings and a belt drive to a maxon gear motor. This figure points to most of the off-the-shelf parts used.

See purchase detail in Terrain-hopper binder (Christian office - red binder).

Figure 2. New steering part maintaining original steering axle position, but replacing with bearings and a belt drive to a maxon gear motor. This figure points to most of the parts that needs workshop assistance. Most of the parts - except axlesl (7 and 8) - can be manufactored on own workshop. The axles will be manufactored by axle supplier.

Maxon motor

The motor for steering is a Gear-motor-encoder combination from Maxon:

GEAR

Planetary Gearhead GP 52
C Ø52 mm, 4 - 30 Nm, Ceramic Version
Outer diameter: 52 mm
Reduction: 81 : 1
Max. continuous torque: 30 Nm
Part No.: 223093 (345€)

MOTOR

RE 40 Ø40 mm, Graphite Brushes, 150 Watt
Part No.: 148867 (347€)
Outer diameter: 40 mm
Type power: 150 W
Nominal voltage: 24 V
No load speed: 7580 rpm
Nominal torque (max. continuous torque): 177mNm

SENSOR

Encoder MR, Type L, 256
CPT, 3 Channels, with Line Driver (5V)
Counts per turn: 256
Number of channels: 3
Line Driver: Yes
Part No.: 225783  (93€)

Sensor has 10 pins, but cable is a 8 pole network cable, cable colors and (pin number (rj45 end))

1 NC
2 VCC - blue/white    (5)
3 GND - blue          (4)
4 nc
5 Ainv - orance/white (1)
6 A    - orange       (2)
7 Binv - green/white  (3)
8 B    - green        (6)
9 Iinv - brown/white  (7)
10 I   - brown        (8)

The Maxon encoder sensor is not used (march 2019)