Transcript autsys.aalto.fi

Midterm report
Autonomous all-terrain vehicle
General
- We have decided to use these common
tools:
- ISO 11783 and CAN fieldbuses
- EPEC as control unit provider
- Additionally each group has selected
instruments suited to their specific problem(s)
Steering group
- Choice between retrofit autosteer for
tractors, commercial autosteer “robot car” kit,
electronic power steering, self-built custom
solution
- Chose an EPS from superatv.com
- Good: robust construction, professional
design
- Bad: complicated installation, low power?
Steering group
- An encoder for the steering wheel angle
- Through-shaft preferred, but not available
soon enough with a large-diameter hole
- A sensor to detect when the steering wheel
is manually turned
Odometry group
- 4 Separate
encoders
- Can not mount
on steady axle
- High durability
requirements
Odometry group
- 102HA encoder by IED
- IP67 casing
- 2500 ppr covers the atv’s full range of
speeds (<1-40 km/h) at reasonable sampling
frequency
- EPEC 5050 controller has specific pulse
inputs and CAN bus
Accelerator pedal and dashboard
Accelerator Pedal and Dashboard
- Dashboard signals intercepted at dashboard
connector, accelerator pedal signals near the
floor
- Unneeded signals passed through T-junction
- EPEC 5050 controller acts transparently or
changes signals with automated control
- Controller installed safely under the seats
Updated timetable
Newly discovered risks
- Risk of EPEC controller not being able to
supply needed 20A current
- Risk of not being able to install EPS system
in time
- Risk that EPS system as it is now isn’t
powerful enough for automatic steering
Midterm retrospect
- Project is behind the schedule
- Weekly meetings raised to 2 times per week
- More sub group communication
- Groupwise the communication has been
good
- Every sub group has always proceeded
between meetings